Abstract: [Objective] β-Sitosterol-modified ginsenoside Rb1 liposomes （β-Rb1-Lip） were prepared to reduce the degradation of Rb1 and enhance the lipid-lowering effects of ginsenoside Rb1. [Methods] β-sitosterol-modified ginsenoside Rb1 liposomes were prepared by the thin-film hydration method. The biosafety of the liposomes was assessed using the MTT assay. The inhibition of lipid droplet accumulation in 3T3-L1 adipocytes by β-Rb1-Lip was investigated using Oil Red O staining and triglyceride （TG） content measurement with an enzyme-linked immunosorbent assay. [Results] The prepared β-Rb1-Lip liposomes had an encapsulation efficiency of 83.74% and an average particle size of 198 nm. The release rate of Rb1 from β-Rb1-Lip was about 80% within 12 hours, demonstrating a good sustained-release effect. Regarding lipid-lowering activity, β-Rb1-Lip at 50 μmol/L showed a significant inhibitory rate of intracellular lipid droplets. Compared to the same concentration of Rb1 monomer, β-Rb1-Lip had a more significant inhibitory effect on the accumulation of lipid droplets in 3T3-L1 cells and did not exhibit cytotoxicity. [Conclusion] β-Rb1-Lip has high encapsulation efficiency, small particle size, and obvious sustained-release characteristics. It can continuously release the active component ginsenoside Rb1, enhance its lipid-lowering efficacy, and reduce the dosage, providing support for the development of Rb1 lipid-lowering products.
Abstract: [Objective] This study aimed to explore the effects of rye pollen peptide on the proliferation of probiotics and promote the development and utilization of rye pollen. [Methods] In this study, A rye flower peptide product with an average relative molecular mass of 691 was obtained by wall-breaking enzymatic treatment of rye pollen raw material. The growth and acid production of Lactobacillus fermentum B153 before and after the addition of rye pollen peptide were also studied to investigate the effect of rye pollen peptide in promoting the proliferation of B153. [Results] The experimental data showed that the 24-h growth and acid tolerance of B153 were improved after the addition of rye pollen peptide, and the logarithmic value of the number of viable bacteria was significantly increased to 8.7 after 24 h of incubation; The lactic acid concentration was significantly increased, and the maximum lactic acid mass concentration was 13 mg/mL. [Conclusion] Rye pollen peptide can improve the growth condition and acid production of L. fermentans B153.
Abstract: [Objective] This study aimed to efficiently utilize the resources of Phlebopus portentosus and develop its polysaccharide functional food. [Methods] The mycelium of P. portentosus was cultured and fermented, and the combined fermentation broth was concentrated at low a temperature and reduced pressure. Then, precipitated by ethanol, separated, purified by DEAE-52 cellulose column chromatography, and the polysaccharide was finally refined by dialysis to remove the small molecular impurities. The total sugar content was determined by phenol-sulfuric acid colorimetry, the monosaccharide composition was determined by liquid chromatography-mass spectrometry (LC-MS), and the impurities such as nucleic acid and protein were detected by ultraviolet spectrophotometer. The structure of polysaccharides was analyzed preliminarily by infrared spectroscopy (IR) and nuclear magnetic resonance spectroscopy (NMR). [Results] The content of total sugar was 84%. The main monosaccharides of the polysaccharide were glucose, mannose, galactose, and arabinose, the molar ratio of which was 2.07∶1.95∶1.00∶1.58. Obvious polysaccharide absorption peaks were shown in the infrared spectrum and nuclear magnetic resonance spectra, through which an α-type pyranose can be inferred in the polysaccharide. [Conclusion] The polysaccharides prepared from the fermentation broth of P. portentosus were mainly composed of four monosaccharides, the structure of which contained α-pyranose.
Abstract: [Objective] This study aimed to study the effect of thermal ultrasound on the physicochemical properties of mung bean milk liquid and the quality of yuba. [Methods] Using mung bean as raw material, mung bean slurry was treated with different thermal ultrasonic conditions and made into yuba. [Results] Compared with untreated slurry, with the increase of temperature, the increase in particle size and thiol content showed a trend of first increasing and then decreasing. At 50 ℃, the particle size of 100 and 150 W increased from 156.27 nm to 208.06 nm and 191.96 nm, and the thiol content increased from 16.83 μmol/L increased to 22.63 μmol/L and 25.35 μmol/L. The endogenous fluorescence spectrum indicates that the higher the temperature, the more tryptophan residues are present in the slurry. The mass of yuba at 100 and 150 W increased from 4.09 g to 5.26 g and 5.08 g, the elasticity increased from 0.08 mm to 0.16 mm and 0.13 mm, and the cooking loss rate decreased from 13.28% to 7.51% and 8.02%, among which the texture characteristics of yuba at 100 W increased significantly, and the cooking loss rate decreased significantly. [Conclusion] Thermo ultrasonic treatment can improve the physical and chemical properties of mung bean milk liquid and the quality characteristics of yuba.
Abstract: [Objective] This study aimed to improve the processing characteristics of collagen. [Methods] Using pig skin collagen and enzymatic hydrolysis pig skin collagen (H-PC) as a control, the antioxidant, emulsification, and other functional properties of the complex after enzymatic hydrolysis and glycosylation (HG-PC) were analyzed. The structure of HG-PC was studied by UV-VIS spectrum, fluorescence spectrum, and Fourier infrared spectrum. [Results] The results showed that compared with PC and H-PC, the DPPH free radical scavenging rate, water retention, emulsification, emulsification stability, foaming stability, and foaming stability of HG-PC were significantly increased (P＜0.05). While the oil retention, surface hydrophobicity, and turbidity of HG-PC were significantly decreased (P＜0.05). The UV absorption intensity of HG-PC was increased, and the fluorescence intensity was decreased, the protein secondary structure of which was destroyed. [Conclusion] The synergistic modification of enzymatic hydrolysis and glycosylation can significantly change the properties of PC, and the synergistic modification effect is better than single modification.
Abstract: [Objective] In order to compare the ability of optical characteristic parameters [absorption coefficient （μa） and approximate scattering coefficient （μ′s）] to identify adulterated tea oil and to explore the enhancement effect of the combination of extraction methods on the model to achieve a faster and more accurate identification of different kinds of adulterated oils. [Methods] In this study, vegetable oils were used as experimental materials to prepare adulterated tea oils with different mass fractions. Different preprocessing methods were used to preprocess the optical characteristic parameter data, followed by feature band extraction and subsequent establishment of a Random Forest （RF） qualitative identification model. [Results] After CRAS and UVE-CARS feature extraction, the identification accuracies of the models built using μa and μ′s were 95.65%, 95.65%, and 98.55%, 97.10%, respectively. The combined extraction method （UVE-CARS） resulted in an improvement of at least 1.45 percentage points in the identification results of the models compared with the CARS feature extraction method. [Conclusion] The identification of different adulterated types of tea oil can be realized more quickly and accurately by using μa. The combined extraction method can effectively improve the identification ability of the model.
Abstract: [Objective] To develop an efficient electrochemical method for the rapid detection of cadmium and lead ions （Cd2+ and Pb2+） in rice samples. [Methods] Designed a portable electrochemical sensor utilizing a disposable screen printed electrode and anodic stripping voltammetry with an isoplated bismuth electrode. This setup was further optimized through square wave voltammetry （SWV）, cyclic voltammetry （CV）, and chronocurrent methods （I-T）. [Results] The proposed approach exhibited outstanding performance with a linear detection range of 20 to 80 μg/L for Cd2+ and 10 to 80 μg/L for Pb2+. The LOD of the cadmium ion were 1.201 0 μg/L, the LOD of the lead ion were 0.963 9 μg/L. [Conclusion] Our newly established electrochemical sensor for heavy metal detection in rice offers high sensitivity, ease of operation, rapid analysis, and aligns with environmentally friendly practices.
Abstract: [Objective] A method for the simultaneous determination of arsenate [As(Ⅲ)], Arsenate [As(Ⅴ)], monomethylarsenate (MMA), dimethylarsenate (DMA), Arsine betaine (AsB), methyl-selenocysteine (MeSeCys) and selenomide in food was developed by high performance liquid phase inductively coupled plasma mass spectrometry (HPLC-ICP-MS), and a total of 10 kinds of arsenic and selenium element forms of As and Se, including acid (SeMet), selenocysteine (SeCys2), selenite [Se(Ⅳ)] and selenate \. [Methods] Taking selenium rich rice as the research object, the best extraction method was determined by comparing different extraction methods and different kinds of enzymes. Moreover, different chromatographic columns, mobile phase composition, mobile phase pH, mobile phase flow, mobile phase methanol content and column temperature were compared to determine the best extraction and separation conditions. [Results] The optimal separation conditions were using Aglient ZORBAX SB-Aq chromatographic column with 20 mmol/L citric acid + 5 mmol/L sodium hexane sulfonate + 4% methanol as the mobile phase gradient with pH values of 4.0 and 6.0 respectively. Elution was performed at a flow rate of 1.0 mL/min, and inductively coupled plasma mass spectrometry (ICP-MS) was detected using HEHe mode. The optimal extraction condition is Tris-HCl (pH 7.5) buffer solution adding 15 mg proteinase K and 15 mg proteinase E. This method can completely separate 10 different forms of arsenic and selenium within 5 minutes. In the range of 0～50 μg/L, the linear relationship between the forms of each element is good, and the correlation coefficient R>0.999 5. The detection limits of As(Ⅴ), MMA, As(Ⅲ), DMA, AsB, Se(Ⅵ), Se(Ⅳ), SeCys2, MeSeCys and SeMet are 0.10, 0.10, 0.12, 0.14, 0.22, 0.15, 0.15, 0.18, 0.12, 0.15 μg/L respectively. The spiked recovery rate ranged from 76.0% to 104.2%, and the relative standard deviation ranged from 1.1% to 8.5%. [Conclusion] This method is simple, fast, highly sensitive and fully meets the requirements for accurate quantitative analysis of arsenic and selenium speciation in selenium-rich foods.
Abstract: [Objective] This study aims to realize the simultaneous determination of fungicide residues in vegetables and fruits. [Methods] A liquid chromatography-tandem quadrupole composite linear ion TRAP-mass spectrometry (LC-QTRAP-MS/MS) method was established for the simultaneous determination of fungicide residues in fruits and vegetables. The samples were salted out with sodium acetate and anhydrous magnesium sulfate in an acetonitrile solution containing 0.1% acetic acid, magnesium sulfate, ethylenediamine-n-propyl silanized silica gel (PSA), octadecylsilane bonded silica gel (HC-C18) and multi-walled carbon nanotubes (MWCNTs) were used for purification. Mass spectrometry was conducted utilizing the enhanced ion scanning mode (MRM-IDA-EPI) and spectral library retrieval technology. The compounds were quantified using an external standard approach, comparing the retention time, ion pairs, and EPI spectral library retrieval. [Results] The 43 kinds of fungicides had a good linear relationship in the mass concentration range of 0.2~5.0 μg/L and 2.5~50.0 μg/L (R2>0.99). The limit of detection (LOD) was 0.1~5.0 μg/kg, and the limit of quantification (LOQ) was 0.4~10.0 μg/kg. The recoveries of the 43 kinds of fungicides were 65.1%～119.8% at three concentration levels, and the relative standard deviations were 0.8%～13.0%. [Conclusion] The established method is rapid, simple, and highly qualitative, and can be used for the screening, confirming and quantitative detection of 43 kinds of fungicides in fruits and vegetables.
Abstract: [Objective] Designing a apace grid-based hand-eye calibration method to reduce robot positioning errors and calibration object Recognition errors in automated food production lines. [Methods] Based on the composition of the attitude matrix, the attitude and position of the end of the robot relative to the camera were obtained by translating and rotating the end of the robot, and a registration method using known corresponding point pairs was proposed to reduce the influence of the robot positioning error on the attitude solution in the translation method. Based on the space circle fitting method, a two-point vector method was proposed to solve the end position, which reduced the amount of data collection. A method of fitting the center of the sphere was proposed to compensate for the result of hand-eye calibration. [Results] The average measured error after calibration is 0.8 mm. [Conclusion] The hand-eye system based on the Eye-In-Hand type, can realize high-precision object positioning.
Abstract: [Objective] Solve the problems of poor control accuracy and adaptability in the Delta robot flexible gripper grasping method. [Methods] This article took the Delta robot flexible gripper as the research object and proposed a Delta robot flexible gripper grasping method that combined multiple models and improved whale algorithm. Established a stable grasping optimization model to seek the optimal contact position on the surface of the grasping object. Established a non-destructive grasping optimization model to minimize contact force while ensuring stable grasping of objects. Combine particle swarm optimization algorithm and whale algorithm to solve the model. The superiority of the proposed grasping method had been verified through experiments. [Results] The proposed method not only had good control accuracy, but also could adapt to objects of different shapes and sizes, with high flexibility and adaptability, success rate of grasping was greater than 96%, grasping damage rate was 0. [Conclusion] The proposed method effectively improves the performance of the Delta robot flexible gripper gripping method and is suitable for sorting fruits, vegetables, and fragile items.
Abstract: [Objective] To meet the requirements of constant and adjustable rotation speed of rolling barrel and constant rotation speed of rolling barrel when tea is rolled. [Methods] The 6CR-55 single-column disc twisting machine was used as the research object in this paper. Fuzzy control algorithm and PWM closed-loop control method were investigated to study the stable control of rotating speed of rolling drum, and established the mathematical model of rotating speed control system of rolling drum based on the STM32 single-chip microcontroller. The simulation experiments of uncorrected, PID and fuzzy PID algorithm control system were carried out by MATLAB. [Results] Compared with uncorrected control and PID control, the output speed of the fuzzy PID speed control system was more stable and accurate, and the anti-interference ability was stronger. The speed error was controlled within 3 r/min. [Conclusion] The fuzzy PID control method can meet the requirement for the constant and adjustable rotating speed of the rolling drum during tea rolling, and improve the rate of tea forming and cell breakage.
Abstract: [Objective] By studying the relationship between the operating parameters of the polishing machine, the motion patterns of rice grains, and the generation of broken rice rates, to seek the basis for optimal parameter control of the polishing machine. [Methods] By analyzing the motion process of rice grains in the polishing chamber, conducting full-factorial experiments, and applying Particle Image Velocimetry (PIV) to analyze the trajectory of rice grain movement, clarifiied the relationship between the motion status of rice grains, the rate of broken rice, and the rotational speed of the polishing machine as well as the opening degree of the pressure gate. [Results] When the pressure gate aperture was set to 20 mm, no coherent motion pattern wwas observed within the experimental range of machine speeds, rendering the rice polishing ineffective. In contrast, with a pressure gate aperture of 4 mm and machine speeds ranging from 600 to 1 400 revolutions per minute, the rice grains exhibited an alternating motion pattern characterized by a relatively small spiral angle and the occurrence of regions with varying velocities. Furthermore, under the condition of a pressure gate aperture of 8 mm and a machine speed of 1 400 r/min, the rice grains demonstrated an alternating motion pattern in regions of high and low velocities (with a velocity difference exceeding 3 m/s). In both of these scenarios, excessive friction and pressure leaded to a high rate of broken rice (exceeding 4%). In the remaining experimental conditions, characterized by appropriate pressure gate apertures and machine speeds, the rice grains exhibited a moderately sized spiral angle in alternating regions of high and low velocities (with a velocity difference of 2～3 m/s). This configuration resulted in a broken rice rate ranging from 2% to 4%, indicative of favorable polishing effects. [Conclusion] The motion patterns formed by rice grains and the resulting broken rice rates vary under different operating conditions. Under suitable opening degree of the pressure gate and rotational speed, rice grains exhibit appropriate motion patterns and achieve better polishing effects.
Abstract: [Objective] In order to solve the problem of uniformity of ice crystal distribution in the process of ice slurry filling. [Methods] Taking broccoli as the research object, the physical model of packing broccoli in carton was established, and the effects of ice filling speed and ice filling Angle on ice crystal distribution uniformity during the ice filling process were analyzed by CFD simulation, so as to determine appropriate ice filling process parameters. [Results] The ice-filling speed and filling angle significantly impact the uniformity of ice crystal distribution. Both excessively low and high ice-filling speeds were detrimental to achieving uniform ice distribution. Tilting the filling angle results in inadequate coverage of fluidized ice on the upper layers of broccoli within the container. [Conclusion] Maintaining a horizontal angle and an ice-filling speed of 3 m/s yields the most uniform distribution of ice crystals, meeting the pre-cooling requirements for broccoli and enabling a certain duration of low-temperature storage.
Abstract: [Objective] The influence of different storage temperatures on the quality and total number of microbial colonies of Premna microphylla Turez jelly was studied, and the shelf-life prediction model based on quality indexes and the total number of colonies were established. [Methods] P. microphylla Turez jelly were stored at temperatures of 1, 4, 10, 15, 20 and 25 ℃, and the hardness, adhesiveness, springiness, chewiness, water holding capacity and total number of colonies were regularly measured. The influence of different temperatures on the quality indexes and the total number of colonies were discussed, and the fitting equations of each monitoring index were determined. According to the quality indexes and total number of colonies of P. microphylla Turez jelly, P. microphylla Turez jelly's shelf-life prediction model was established by combining the Arrhenius model and Belehradck model. [Results] The results show that the different storage temperature has no significant change in springiness, while the storage temperature has a significant effect on the hardness, adhesiveness, chewiness, water-holding capacity, and total number of colonies. The zero-level response equation was the best fit for the change in water holding capacity of P. microphylla Turez jelly, with an average fit of 0.978. On the influence of hardness, viscosity, and chewability, the first-order reaction had the best fitting, and the average fitting degree was 0.967, 0.904, and 0.977, respectively. The Logistics equation had the best fitting effect on the total number of colonies of P. microphylla Turez jelly, and the average fitting was 0.992. Five shelf-life prediction models were validated under the storage temperature of 3 ℃. The relative errors between the measured and predicted values were 7.50%, 8.13%, 4.38%, 5.00%, and 3.75%, respectively, with good prediction results. [Conclusion] The models can effectively predict the shelf life of P. microphylla Turez jelly under storage conditions from 1 ℃ to 25 ℃.
Abstract: [Objective] To establish a nondestructive detection method for fruit appearance. [Methods] Nectarines were used as the research subject. The IQQU3 smart phone camera was used to capture the picture data, which was then preprocessed. The image annotation program Labelimg was used to label the data. Panning, left-right flipping, and mirror flipping were used to enlarge the data. Using an ratio of 8∶2, the enlarged photos were split into training and test sets. Lastly, the data was trained for 150 epochs using five YOLOv8 models （n, s, m, l, x）. The training results of the five models were compared and analyzed in order to determine which detection model was the best. [Results] The nectarine dataset was constructed, there were 4,205 total photos; YOLOv8 （n, s, m, l, x） the total loss values in the training set were 2.275, 1.778, 1.482, 1.880, and 1.401, respectively, The total loss values of the test set were 2.724, 2.253, 2.057, 2.105, and 2.004, respectively; YOLOv8 （n, s, m, l, x） precision were 94.0%, 98.0%, 97.4%, 97.3%, 97.9%, respectively, The recall were 95.4%, 95.5%, 95.9%, 96.9%, and 96.9%, respectively. In a comprehensive comparison YOLOv8s was the better model, and the average detection accuracy mAP_0.5 was 97.8%. The average precision of fresh, bruise and scar were 96.2%, 98.8% and 98.4%, respectively. The inference time and calculation amount （GFLOPs） were 179.4 ms and 28.4 respectively. [Conclusion] YOLOv8 can effectively detect the quality of fruit appearance, which can be used for non-destructive testing of fruit appearance, and this study can provide new ideas for non-destructive testing of fruits.
Abstract: [Objective] Aiming at the problems of low accuracy and poor robustness in the previous classification methods based on artificial features. [Methods] A strong generalization automatic classification method of potato shape and size was proposed in this study. First, two potato ViT models were built based on Transformer model to complete potato shape grading and size grading tasks in parallel. Secondly, a robust model was trained by using migration strategy and data augmentation method. Finally, the effectiveness of this method in potato grading was verified by quantitative analysis of test sets. [Results] The experimental results show that the potato ViT model achieves 96.36% and 94.75% for potato shape classification, and 89.66% and 85.16% for size grading in terms of accuracy and μF1 index. The classification accuracy was better than VGG16, ResNet50 and MobileNetV3 network models. [Conclusion] The results shows that it is feasible to apply the proposed method for the real-time and accurate detection of potato shape and size. The results of this study can provide theoretical and technical support for potato intelligent grading.
Abstract: [Objective] Achieving non-destructive testing of sub-healthy watercore apples. [Methods] First, the logarithmic function method and the power function method proposed by this study were used to correct the sample spectra. Subsequently, the corrected data were converted into different images of gramian angular difference field (GADF), gramian angular summation field (GASF), markov transition field (MTF), recurrence plot (RP), symmetric dot pattern (SDP). Then, the ResNet50 network model with the convolutional block attention module (CBAM) was used to mine the deep image features related to the degree of watercore, which were downscaled by the t-distributed stochastic neighbor embedding (t-SNE) method and analyzed by clustering to determine the most suitable image transformation method. Finally, the most suitable image features were inputted into the improved particle swarm algorithm (IPSO) optimized support vector machine (SVM), extreme learning machine (ELM), k-nearest neighbour (KNN) and random forest (RF) classifier for the three-class classification of watercore apple. [Results] The results showed that the power function method was better than the logarithmic function method in eliminating the effect of diameter on the transmission spectrum. The silhouette coefficient (SC), the calinski harabasz score (CHS), and the davies- bouldin index (DBI) were 0.93, 0.88 and 0.24 after visualization of the image features in the GADF, better than the rest of the image transformation methods. ResNet50-IPSO-ELM achieved the highest classification accuracy of 96.8%. The overall discrimination accuracy of the three watercore classes apples in the test set reached 96.3%, and the stable precision (SP), stable recall (SR), and stable F1-score (SF) were 87.2%, 95.8%, and 92.3%, respectively. [Conclusion] The model maintains a high classification accuracy for the majority class of apples without watercore and healthy apples with watercore and a high discriminatory ability for the minority class of sub-healthy apples with watercore.
Abstract: [Objective] This study aimed to investigate the effects of high fat diet and high fat and high fructose diet on uric acid level and liver and kidney function in hyperuricemia (HUA) rats. [Methods] 24 rats were randomly divided into control group, model group, high-fat diet group and high-fat and high-fructose diet group. All rats were fed with the corresponding diets, except the control group, 500 mg/kg potassium oxazinate and 100 mg/kg adenine per day. After 6 weeks, serum biochemical indexes such as uric acid and creatinine were determined, and pathological examination of kidney and liver was performed. [Results] The uric acid content of control group, model group, high-fat diet group and high-fat high-fructose diet group were 118.10, 319.05, 325.71, 456.10 μmol/L, respectively. The levels of uric acid and creatinine in the high-fat diet group were not significantly different from those in the model group, but the kidney injury and liver fat accumulation were more serious. The uric acid in the high-fat and high-fructose group was significantly higher than that in the model group, and the degree of kidney injury and liver fat accumulation was more serious than that in the model group. [Conclusion] High-fat diet cannot further increase the uric acid content of HUA rats, but can aggravate the liver and kidney damage of HUA rats. High-fat and high-fructose diet will further increase the uric acid content of HUA rats, and aggravate kidney injury and liver fat accumulation. Hyperuricemia group should pay attention to control the intake of dietary fat and fructose.
Abstract: [Objective] A solid beverage with antialcoholic function was developed by the raw materials of tangerine peel, hawthorn and Pueraria lobata, which had the same origin as food and medicine, and explore its protective effect on mice with acute alcoholic liver injury. [Methods] The dry paste rate and total flavone content were used as the indexes，the extraction process was selected by orthogonal test. The single factor method was used to optimize the forming process with the indexes of sensory evaluation, shaping rate and solubility. A mouse model of acute alcoholic liver injury was established by administering 52% alcohol. The liver index, aspartate aminotransferase （AST） and serum alanine aminotransferase （ALT） in serum, as well as total cholesterol （TC）, triglyceride （TG）, superoxide dismutase （SOD）, malondialdehyde （MDA）, glutathione （GSH）, the inflammatory factor IL-1β, IL-6, TNF-α in liver tissue were measured. The pathological changes of the liver were observed by hematoxylin-eosin （HE） staining. [Results] The optimal preparation process of tangerine peel composite solid beverage: three herbs were soaked for 30 minutes and extracted twice. The first solid-liquid ratio was 1∶12 （g/mL） and the extraction time was 2.0 h, and the second solid-liquid ratio was 1∶10 （g/mL） and the extraction time was 1.5 h. And then combined the two extracts. After concentration, drying and crushing, dry paste powder was obtained, mixed with maltodextrin in a 1∶1 ratio, added 1.0% mogroside, and used 90% ethanol as wetting agent for wet granulation. The results of animal experiments show that: compared with model group, the levels of AST, ALT, TG, TC, MDA, IL-1β, IL-6, TNF-α were reduced （P＜0.01, P＜0.05） by the pretreatments with tangerine peel composite solid beverage, and the levels of GSH, SOD were increased （P＜0.01）. The histopathological sections of the liver showed significant improvement in the degree of hepatic injury in the administered mice. [Conclusion] tangerine peel composite solid beverage has uniform color, good solubility, moderate sweetness and delicate taste, and has good protective effect on acute alcoholic liver injury.
Abstract: [Objective] To investigate the effect of β-hydroxy-β-methylbutyrate （HMβ） supplementation on muscle protection in taekwondo players during training. [Methods] 18 male subjects above the second level of the Taekwondo special Team who voluntarily participated in the experiment were recruited and divided into experimental and control groups （9 each） according to the conditions. The experimental group consumed one sachet （25 g/bag, the amount of HMβ added was 500 mg/bag） of HMβ-added milk powder before and after training （with a break of more than 30 min） in the morning and afternoon from Monday to Saturday, while the control group consumed the same amount of commercially available regular milk powder. Blood samples were collected before and after the intervention and on Monday mornings to analyze the changes in biochemical indicators, and quantitative tests of Taekwondo-specific abilities were performed before and after the experiment. [Results] Compared with the control group, the experimental group did not see significant changes in the pro-inflammatory factor interleukin-6, plasma glutamine levels were significantly increased （P<0.05）, and plasma glycine levels did not see a significant decrease after intervention; Myoglobin was significantly decreased in the experimental group after intervention （P<0.05）, and serum levels of total cholesterol, triglyceride, and LDL cholesterol were significantly lower than those of the control group （P<0.05）. The decrease of blood urea nitrogen was smaller than that of the control group; The number of 20-second in situ knee lifts and the number of 30-second tuck jumps in the experimental group were both improved and increased more than that of the control group. [Conclusion] HMβ supplementation during training can exert protective functions by reducing inflammation, improving immune function, maintaining muscle membrane stability, increasing nitrogen stores, and strengthening muscle remodeling ability, improving muscle adaptability to training to ensure their competitive status.
Abstract: [Objective] This study aimed to optimize the fermentation process of quinoa-haskap complex fruit fermentation supernatant and develop anti-exercise fatigue food with high nutritional value. [Methods] Using black quinoa and haskap as raw materials, yeast combined with Lactobacillus for collaborative fermentation, the fermentation process conditions of composite fermentation juice were optimized by single factor and orthogonal test, and its anti-exercise fatigue effect on mice was deeply investigated based on animal experiments. [Results] The optimum fermentation conditions of quinoa-indigo fruit complex juice were as follows: initial pH 4.0, fermentation time 32 h, fermentation temperature 37 ℃, white sugar content 8%, and the activity of superoxide dismutase in the fermentation product was 253.49 U/mL. In vitro antioxidant tests showed that composite quinoa-haskap complex fermented supernatant had strong antioxidant effect and proportional to the concentration of antioxidant. The results of animal experiments demonstrated that different doses of quinoa-haskap fruit complex juice fermented supernatant prolonged exhaustive swimming time of mice, significantly reduced serum urea nitrogen and other indexes, and significantly increased liver and muscle glycogen reserves (P＜0.05). [Conclusion] The supernatant of quinoa and haskap fruit complex juice under optimal fermentation conditions has strong antioxidant activity and can improve the exercise endurance of mice.
Abstract: [Objective] This study aimed to realize the high value-added resource utilization of walnut production waste. [Methods] Ultrasonic assisted tartaric acid was used to extract pectin from walnut peel. The extraction process was optimized by response surface test, and its lipid-lowering ability and antioxidant activity were analyzed. [Results] Under the control of the conditions of ultrasonic power of 300 W, ultrasonic temperature of 95 ℃, ultrasonic time of 27 minutes, liquid to material ratio of 19∶1 （mL/g）, and pH of 2, the yield of walnut green peel pectin was the highest, reaching 25.92 mg/g. Walnut green peel pectin had good adsorption capacity for cholesterol, binding capacity for bile salts, and inhibitory effect on pancreatic lipase. Walnut green peel pectin also had strong antioxidant effects. When the concentration was 2 mg/mL, the clearance rates of hydroxyl radicals, DPPH radicals, and ABTS radicals reached （78.74±0.58）%, （91.56±1.27）%, and （97.89±0.72）%, respectively. [Conclusion] High-quality walnut green peel pectin could be obtained by optimizing the ultrasonic assisted tartaric acid extraction process. This pectin had good lipid-lowering function and antioxidant activity, and can be used as natural pectin resources for further research and development.
Abstract: [Objective] To improve the production efficiency of the oligosaccharide industry. [Methods] Isomaltooligosaccharides 50 syrup was used as the raw material, and purified by sequential simulated moving bed chromatography. Potassium ion resin was selected as the suitable separation medium by preparative chromatography single column experiment. Then, based onthe principle of material balance and the basic principle of sequential simulated moving bed, the initial operating parameters of separation process were approximately established. Further the separation conditions were optimized. [Results] The best technical parameters were as follows: feed refraction was 60% and column temperature was 65 ℃. At the same time quantity of flow in the entrance and eluent were 455 mL/h and 682 mL/h, respectively. The velocity of flow in the entrance and eluent were 37.4 mL/min and 29.6 mL/min, respectively. Besides, the circulating flow was kept within 364 mL/h. Finally, the outlet refraction of isomaltooligosaccharides was 20.40% with the purity of 90.20% and the yield of 85.50%. [Conclusion] The sequential simulated moving bed chromatographic separation equipment independently developed by the laboratory can efficiently purify isomaltooligosaccharides.
Abstract: [Objective] This study aimed to improve the quality of Yanbian yellow beef during storage. [Methods] Yanbian yellow cattle eye meat and buttocks were used as experimental materials. Low frequency and high intensity (power 360 W, frequency 40 kHz) ultrasound technology was used to treat beef, and the effects of different ultrasound treatment time (0, 40, 60, 80 min) on the physical and chemical properties of beef during 10 days of storage were investigated. [Results] Extending ultrasonication treatment time significantly decreased the shear stress and redness value of beef (P＜0.05). Moreover, the analysis of myofibrils in beef after ultrasonic treatment showed that the microfibril fragmentation index increased significantly with the extension of ultrasonic time (P＜0.05). [Conclusion] Ultrasonic treatment for 80 min resulted in the lowest shear stress, the highest MFI and the best tenderness.
Abstract: [Objective] This study aimed to improve the organic selenium content of quinoa seeds and develop high-quality Se-rich quinoa food raw materials. [Methods] Using Qingbaili No. 1 quinoa as raw material and sodium selenite as a selenium source, the selenium-enriched germination process conditions of quinoa were optimized through one-way experiments combined with orthogonal experiments. The soluble protein, polyphenol content, and antioxidant capacity of selenium-enriched quinoa were further analyzed. [Results] The optimal process conditions for selenium-enriched germination of quinoa were sodium selenite solution concentration of 20 mg/L, soaking temperature of 25 ℃, soaking time of 6 h, soaking solution pH of 7.0, germination time of 48 h, and germination temperature of 20 ℃. Under these conditions, the organic selenium content of selenium-enriched germinated quinoa was 349.52 μg/kg. Selenium-enriched sprouted quinoa had the highest content of free phenols (236.35 mg/100 g) and bound phenols (198.31 mg/100 g), and control deionized water germinated quinoa had the highest content of soluble protein (22.18%). Notably, the antioxidant activities of soluble protein, free phenols, and bound phenols in selenium-rich germinated quinoa were the strongest, followed by those in control deionized water germinated quinoa, and untreated quinoa was relatively the lowest. [Conclusion] Se-enriched germination can significantly increase the contents of organic selenium, soluble protein and polyphenols, and enhance the antioxidant capacity of Quinoa.
Abstract: [Objective] To improve the drying quality of pumpkins. [Methods] This study conducted experiments on hot air drying, vacuum drying, and combined hot air-vacuum drying, these drying characteristics were evaluated and compared based on unit energy consumption, rehydration ratio, and color difference indicators. Combining BP neural network model with genetic algorithm, combined with entropy weight and weighted scoring method, a multi-objective comprehensive optimization was carried out for the combined hot air-vacuum drying of pumpkins. [Results] Under the same conditions, the highest drying efficiency was hot air drying; And the findings revealed that at drying temperatures was 55 ℃, with a moisture content transition point of 30%, the combined drying method reduced the drying time by 52.63%, compared to vacuum drying. The lowest unit energy consumption was vacuum drying; The worst rehydration performance was hot air drying. The best color was vacuum drying. The optimal drying parameters determined by the genetic algorithm combined with a BP neural network model were a hot air drying temperature of 65 ℃, conversion point moisture content of 50%, and vacuum drying temperature of 56.050 9 ℃. Verification experiments demonstrated that the average relative errors between the genetic algorithm optimized values and the experimental values for unit energy consumption, rehydration ratio, and color difference were 2.5%, 5.53%, and 4.84%, respectively, all lower than 6%. [Conclusion] The combined hot air-vacuum drying of pumpkin integrates the advantages of both hot air drying and vacuum drying, and combined with BP neural network genetic algorithm model can optimize the process parameters for pumpkin hot air vacuum drying.
Abstract: [Objective] This study aimed to optimize the process of deep eutectic solvent extraction of flavonoids from exocarpium Citri grandis and to evaluate its antioxidant activity. [Methods] The type of deep eutectic solvent system, the water content of deep eutectic solvent, material-to-liquid ratio, extraction temperature, and extraction time were selected as experimental variables, and the yield of flavonoids was used as response variables to conduct single factor experiment. Then the single factors with significant differences were screened to optimize the process of deep eutectic solvent extraction of exocarpium C. grandis flavonoids by response surface methods. Finally, the scavenging ability of exocarpium C. grandis flavonoid extract on DPPH radicals, ABTS radicals, and hydroxyl radicals was explored to analyze the antioxidant activity. [Results] The highest yield of exocarpium C. grandis flavonoid was obtained by the choline chloride-glycol system. The yield of flavonoids was significantly impacted by the deep eutectic solvent's water content, the material-to-liquid ratio, and the extraction temperature. The response surface method was used to determine the ideal flavonoid extraction procedure, which included the deep eutectic solvent's water content of 43%, the material-to-liquid ratio of 1∶21 (g/mL), and the extraction temperature of 60 ℃. The yield of exocarpium C. grandis flavonoids was (19.31±0.47) mg/g. The results of antioxidant activity showed that the concentration for 50% of maximal effect values of DPPH radical, ABTS radical, and hydroxyl radical scavenging were (117.61±1.71), (36.91±0.46), (387.52±1.85) μg/mL. [Conclusion] The extraction of exocarpium C. grandis flavonoids using deep eutectic solvent resulted in significantly higher yields compared with conventional water and ethanol method. These flavonoid extracts had potential as a source of natural antioxidants.
Abstract: In recent years, with the emergence of resistance to traditional antibiotics and the growing interest in the development of natural antimicrobials, natural antimicrobial peptides have received extensive attention. Among them, plant-derived antimicrobial peptides have the characteristics of low drug resistance, wide antibacterial spectrum and low toxicity, and because of rich cysteine residues, they can form multiple disulfide bonds, so they have high chemical, thermal and enzymatic hydrolysis stability. In this paper, the classification of plant antimicrobial peptides and the methods of extracting and screening antimicrobial peptides from plant sources were reviewed. The potential applications of plant antimicrobial peptides in the field of food were emphasized, and the screening and future applications of these plant antimicrobial peptides in the field of food were prospected.
Abstract: Antibacterial peptides have unique antibacterial mechanisms different from antibiotics, which are safe and less likely to cause bacterial resistance. Antibacterial peptides have significant advantages and extremely broad application prospects, which have the potential to become one of the widely used antimicrobial substances in the food industry. Currently, Nisin is allowed as food preservative. However, the promotion and application of antimicrobial peptides are still limited by high production costs, single antibacterial activity, and poor stability. The use of compound preservative technology and coating preservation technology can effectively improve the antibacterial efficiency by combining antimicrobial peptides with other natural preservatives. In addition, recombinant expression technology is the most economically valuable and scientifically effective way to achieve large-scale production of antimicrobial peptides, and the stability of antimicrobial peptides can be achieved through artificial intelligence design and optimization of their structure. This review summarizes the current application status and biosynthesis research progress of antimicrobial peptides in the food industry, and puts forward thoughts and suggestions on the existing problems and research prospects.
Abstract: Gardenia fruit oil is an edible vegetable oil extracted from gardenia fruit, which possesses various health benefits including antioxidation, anti-inflammation, anti-cancer, anti-depressant, and liver protection. Its unsaturated fatty acids account for more than 70% of the total fatty acids, and it also contains phenolic acids, tocopherols, phytosterols and other active components. In this review, the extraction process, nutritional composition and health effects of gardenia fructus oil were systematically introduced, and the key work that should be focused on the high-value utilization of gardenia fructus oil in food, cosmetics and biomedicine was prospected.
Abstract: Based on recent domestic and foreign research results, the health care function and fruit wine development of Aronia melanocarpa were reviewed. The types and technology research progress of the fruit wine were emphasized, and the challenges and opportunities of current development of the fruit wine were analyzed.
Abstract: The extraction and purification methods of polysaccharides from edible fungi determine their structure, which in turn affects their biological activity, and is the basis of research on edible fungi polysaccharides. Some specific structural features make the biological activity of edible mushroom polysaccharides significantly enhanced. Therefore, researchers have used physical, biological and chemical methods to modify the molecular structure of edible mushroom polysaccharides to improve their biological activity. The review introduced the extraction, purification and structural modification methods of edible fungi polysaccharides. The advantages and disadvantages of extraction, purification of polysaccharides from edible fungi, and the effects of chemical modification on their structure and biological activity were summarized. The importance of appropriate extraction and purification methods for obtaining the target polysaccharides and the importance of chemical modification methods for changing the molecular structure and improving the functional properties and biological activities of polysaccharides from edible fungi were prospected.
Abstract: Objective: Analyzed the workspace of 6-DOF food handling robot and planed the motion trajectory, so as to provide basis for the layout of food handling platform in workstation and the motion control of robot. Methods: Composition and structure of the robot were analyzed, the kinematics model was established, and the kinematics model was verified by MATLAB. Based on this, the workspace of the robot was modeled and solved, the working area of the robot was obtained, and the reasonable layout position of the food handling table was given; combined with the requirements of food handling task, a three-stage quintic polynomial interpolation method was proposed for robot end trajectory planning. The effectiveness of this method was verified by MATLAB simulation and experiment. Results: The reasonable layout space of the food handling table was the area of z＞0 mm and 200 mm＜r＜500 mm. The method of three-stage quintic polynomial trajectory planning can make the robot perform the food handling task smoothly, and increase the accurate control of the point position, speed and acceleration of the robot. Conclusion: The method of three-stage quintic polynomial trajectory planning is effective for the robot to perform the food handling task.
Abstract: This review introduced the classification, structure and physical and chemical properties of dietary fiber, and summarized the relevant research literature on the modification methods and physicochemical properties of dietary fiber at home and abroad in recent years. The development direction of the physicochemical properties of dietary fiber and its modification methods were also prospected, in order to provide a theoretical reference for its efficient and comprehensive utilization.
Abstract: Based on the scientific theory of modern nutrition and functional food science, this paper uses biotechnology and information digital technology to establish a more precise, flexible, integrated and digital functional food research and development system-flexible precise nutrition intervention system (FPNIS) which improves the shortcomings of the two common functional food research and development models that are based on traditional Chinese herbal medicines or simple ingredient dietary supplements. Through the establishment of FPNIS, provide a new way to explore the research and development of efficient and precise functional food, and analyze its trend.
Abstract: Objective:Improve the quality of dried okra products.Methods:The rehydration ratio, shrinkage rate, vitamin C content, drying time and sensory score were used to analyze the effects of different pretreatment methods on the quality of dried okra products, and the coefficient of variation method was used for comprehensive weighted evaluation.Results:The results showed that blanching and ultrasonic pretreatment can significantly increase the rehydration ratio of the dried sample (P＜0.05). The shrinkage rate was most affected by blanching. The vitamin C content of the pretreatment group was lower than that of the control group, and the ultrasound treatment group had the least loss. The blanching and ultrasonic pretreatment can shorten the drying time, and sensory scores of samples pretreated by ultrasound and color protection were significantly higher than those pretreated by blanching (P＜0.05). The comprehensive evaluation by the coefficient of variation method showed that the quality of the okra pretreated by ultrasonic was the best, followed by the color protection treatment, and the blanching treatment had the lowest comprehensive score. When the ultrasonic pretreatment temperature was 20 ℃, the comprehensive score of the dried sample obtained was the highest, which was 0.907.Conclusion:The research showed that the ultrasonic pretreatment was a better pretreatment method with hot air drying of okra.
Abstract: Objective: This study focused on improving the production of chitosan oligosaccharides by chitinase degradation of chitin. Methods: Using genetic engineering methods to clone, prokaryotic expressing, and investigating enzymatic properties of the chitinase from Streptomyces diastaticus, and the chitinase activity was explored by homology modeling, amino acid comparison of the catalytic domain, and site-directed mutagenesis. Results: After cloning and prokaryotic expression, the enzyme production cycle was shortened from 7 d to 24 h, and the enzyme activity reached 132 U/L, which was 32% higher than the original bacterial enzyme activity (100 U/L). The amino acids that determine the activity of chitinase was Asp at position 128, 130, and Glu at position 132 of the catalytic domain. Conclusion: Clonal expression of the chitinase gene resulted in a shorter enzyme production cycle and increased enzyme activity.
Abstract: Objective:This study aimed to provide strategy for controlling the fungal diseases of postharvest blueberry in Sichuan province.Methods:The pathogenic bacteria from 14 planting bases in Sichuan Province were isolate, identified, pathogenicity determination. Moreover, the effects of temperature and light on mycelia growth of the dominant and subdominant strains of blueberry after harvest were studied, and the effective natural antibacterial components against them were screened.Results:The blueberry postharvest rot diseases were caused by the following nine kinds of fungi:Aspergillus niger,Aspergillus tubingensis,Neofusicoccum parvum,Neopestalotiopsissp.,Fusarium graminearum,Alternaria alternata,Mucor fragilis,Penicilliumsp.,Cladosporium xylophilum.Aspergillus niger was the dominant species with the highest isolation frequency and the most pathogenic, andNeopestalotiopsissp.,Alternaria alternata,Penicilliumsp.,Cladosporium xylophilum were the subdominant species with isolation frequencies greater than 10%. The optimum growth temperature ranged from 20 ℃to 35 ℃of dominant and subdominant strains of blueberry postharvest. The effects of light on the mycelia growth ofA. niger，Neopestalotiopsissp., A. alternata,and C. xylophilum were significant，but that was insignificant on the growth ofPenicilliumsp.strains. Thymol showed good broad-spectrum antibacterial activity, the EC50 values of dominant and subdominant strains of blueberry postharvest was 30~50 mg/L, while the thymol applied directly to blueberry postharvest fungal control in aqueous solution should not be higher than 50 mg/L.Conclusion:Thymol is more effective on postharvest diseases of blueberry in Sichuan province.
Abstract: Objective:In order to preserve more volatile components of celery and reduce its moisture content. Methods:A hot-air coupled microwave drying system based on aroma detection was designed. An electronic nose (PEN3) was applied to detect volatile components, assisted with GC-MS to measure the specific content of volatile components. Based on constant temperature drying (50, 60, 70 and 80 ℃), sensor 7 and 9 were chosen for subsequent combined control. Results:Comparing with constant temperature drying, the combined control drying using volatile compounds detection could retain more volatile substances, and a good balance had been achieved between the quality of the dried product and the drying rate. The drying time of combined control was 67 min, closing to constant temperature drying at 70 ℃ (63 min). Meanwhile, optima color difference (16.313±1.745) and sensory evaluation (28.9) were obtained under combined control drying. Conclusion:Microwave coupled hot-air drying control of celery stalks based on volatile compounds detection could be applied to produce high-flavor celery stalks.
Abstract: Objective:The flavor formation process of stewed pork was investigated in this study. Methods: Electronic nose and gas-phase mass spectrometry (GC-MS) techniques were used to compare the key processes such as bleaching, frying, stewing and addition of sauces during the processing of stewed pork, and to analyze the changes of flavor compounds. Results: The results of electronic nose measurement were consistent with the results of gas chromatography analysis. The flavor content of raw pork and sauces was the highest, and the flavor substances decreased in the blanching, frying and stewing stages. However, the characte-ristic flavor substances were formed continuously. A total of 148 compounds were detected by GC-MS, including 39, 32, 23, 20, 38, and 65 compounds in raw pork, blanched, fryed, stewed and finished products and sauces, respectively, which mainly produced aldehydes and ketones, esters and alcohols, heterocyclic compounds, and aromatic hydrocarbons and their derivatives. The characteristic flavors of finished products were hexanal, benzaldehyde, 1-octen-3-ol, cinnamaldehyde, 2-pentylfuran, 2-acetyl pyrrole, 2,3-dimethyl-5-ethylpyrazine, etc. The content of acetoin was higher in the pre-preparation stage of stewed pork, while methoxy-phenyl-Oxime stayed high in all of the processes. Conclusion: The electronic nose technique can be used to detect the changes of flavor substances in different processing stages of stewed pork, but the specific substance changes need to be determined and analyzed by GC-MS.
Abstract: An analytical method for the simultaneous determination of 19 kinds of organochlorine pesticides in apple-pear was established based on optimized solid-phase extraction coupled with gas chromatography-mass spectrometry（SPE-GC/MS）. Different extraction conditions, included extraction solvent, extraction solvent volume, sample weight, solid phase extraction clean-up and eluent were optimized during the sample pretreatment. The quantification were analyzed by GC/MS in selected ion monitoring （SIM） mode and the external standard method. The method showed good linearity (R2≥0.996 7) for all the pesticides. The recoveries at three spiked levels (20, 40, and 200 μg/kg) ranged from 86.1% to 108.9% with the relative standard deviation below 10%. The limit of detection ranged from 3 to 6 μg/kg and the limit of quantification ranged from 10.0 to 20.0 μg/kg the for 19 kinds of pesticides, respectively. The method was simple, accurate and showed high sensitivity for screening and detection of the 19 kinds of pesticides in apple-pear.
Abstract: Objective:This paper proposed a genetic fuzzy PID cascade control system. Methods:Taking the outlet temperature as the main control quantity and the inlet temperature as the secondary controlled quantity, a cascade control system was made. The genetic fuzzy PID controller was used to control the main loop, and the PI controller was used to control the secondary loop. Results:Compared with conventional PID control, the cascade genetic fuzzy PID control had the advantages of shorter regulation time, better robustness. Conclusion:The genetic fuzzy PID cascade control system for soy flour spray drying tower can improve the quality of soy flour production.
Abstract: Objective: To accurately distinguish intact peanut, nut damaged peanut and epidermis damaged peanut. Methods: A peanut seed integrity detection scheme based on deep learning convolution neural network (CNN) was proposed. The peanut seed color selection system was established and a peanut seed image database was also established; The improved density peak clustering (DPC) algorithm was used to adaptively compress the CNN convolution kernel to effectively balance the network depth and operation efficiency; The improved sparrow search algorithm was used to optimize the CNN super parameter configuration and network structure, and the CNN model suitable for peanut grain integrity detection was obtained. Results: Compared with other detection methods, this scheme improved the recognition accuracy by about 5.41%~13.92%, and the detection time of single image of peanut grain was shortened by about 16.9%. Conclusion: This method effectively improves the accuracy and real-time of peanut grain integrity detection.
Abstract: Objective: To improve the development and utilization rate of Lycium barbarum in the saline-alkali land of the Yellow River Delta. Methods: Ultraviolet spectrophotometer was used to determine the scavenging effect of Lycium barbarum oligosaccharide on free radicals and its effect on the growth curve and pH value of Bifidobacterium adolescentis, so as to determine its antioxidant performance and the ability to proliferate probiotics. Results: The concentration of Lycium barbarum oligosaccharide reached 2.0 mg/mL, the maximum scavenging rates of DPPH·, ABTS+ and hydroxyl radical reached (65.32±0.03)%, (99.93±0.05)% and (21.86±0.01)%, respectively, when the concentration was between 0.1~0.5 mg/mL, it showed good total reducing power. The OD value of Bifidobacterium adolescentis increased with the increase of Lycium barbarum oligosaccharide concentration, and the pH value was negatively correlated with the cell concentration. Conclusion:Lycium barbarum oligosaccharides show strong antioxidant activity and the ability to proliferate probiotics.
Abstract: Objective:Two kinds of titration methods (automatic potentiometric titration and indicator titration) of GB 5009.229 and GB 5009.227 were used to analyze the expanded uncertaintyof the determination of acid value and peroxide value in edible oil.Methods:CNAS-GL006 was used for the uncertainty component and extended uncertainty of the measurement results of the two titration methods.Results:The results showed that the standard solution was the main factor affecting the uncertainty of acid value (value) and peroxide value.Conclusion:The effects of the two titration methods on peroxide value and acid value (value) of edible oil is relatively small, and the appropriate titration method can be selected according to the actual situation for the basic testing organization.
Abstract: Objective:To monitor and control mold spores contamination effectively in food (beverage) processing workshops.Methods:The mold spores are enriched and classified by microfluidic chip, and the air aerosol was collected in 2~10 micron channel and prepared on film. Finally, spore images were taken by camera and electron microscope, and spores were detected, distinguished and counted by Canny algorithm.Results:Compared with the traditional falling plate method, the detection device designed in this paper could detect 103cell/mL mold spores sprayed in the air within 20 minutes.Conclusion:Using airborne UAV to detect mold pollution in food (beverage) processing workshop in the air is simple and feasible.
Abstract: Objective:This study aimed to explore the effect of Pediococcus pentosaceus J8 fermented kiwifruit on bread baking and flavor profile characteristics of wheat bread. Methods: The changes in β glucosidase enzyme activity, organic acids and flavor compounds during kiwifruit fermentation were analyzed. The physical and chemical properties of wheat dough incorporated with fermented kiwifruit were determined. Moreover, the changes in total dietary fiber and total amino acid content, bread quality and flavor characteristics of the resulted bread were also determined. Results: After 15.5 hours of fermentation, the β glucosidase activity reached 55.13 U/L, and the content of lactic acid and acetic acid significantly increased. A total of 110 flavor compounds were detected by GC TOF/MS in kiwifruit. After fermentation, the content of acids, esters, alcohols and terpenes increased, while the content of aldehydes and ketones decreased. For the first time, α angelica lactone, furfuryl acetate and pantolactone were found in kiwifruit. In dough, compared with the unfermented group, the α amylase and protease activities increased by 14.86% and 18.63%, respectively after incorporation of fermented kiwifruit. In bread, compared with the unfermented group, the hardness (11.58%) decreased, while the soluble dietary fiber, total amino acids and specific volume increased by 12.54%, 41.02% and 18.59%, respectively. In addition, bread incorporated with fermented kiwifruit tasted better, had an increased content (27.78%) and type (45.10%) of flavor compounds and a higher overall acceptability than bread incorporated with unfermented kiwifruit. Conclusion: Fermenting kiwifruit with Pediococcus pentosaceuscan improve the flavor and baking characteristics of bread.
Abstract: Objective: This study aimed to provide theoretical support for the processing application of surimi products by comparing the gel characteristics of Chinese herring surimi and the common surimi. Methods: The surimi gels of Chinese herring, silver carp, white croaker and golden-thread fish were prepared, and the difference of gel strength, texture profile analysis (TPA), gelation index, gel deterioration index, water retention, whiteness and microstructure among the four kinds of surimi were investigated. Results: The hardness, chewiness, adhesiveness, gel strength and water retention of Chinese herring surimi were significantly higher than the those of silver carp surimi (P＜0.05). The above results were consistent with the microstructure properties of Chinese herring surimi gel which appeared a smooth, dense and porely unifrom surface. Moreover, the whiteness of Chinese herring surimi (71.23±0.09) was significantly higher than that of white croaker surimi (67.81±0.25) and white croaker surimi (67.16±0.55). Conclusion: The Chinese herring surimi has the advantages of both freshwater and seawater surimi in gel strength, whiteness, water retention and microstructure formation.
Abstract: Objective:This experiment is to judge the comprehensive quality of Hunan bacon.Methods:The contents of 8 biogenic amines in Hunan bacon were determined by HPLC-UV. The contents of moisture content, peroxide value and nitrite were measured.Results:The facts showed the total amount of biogenic amines was 127.22~166.24 mg/kg, which were mainly composed of cadaverine, putrescine, spermine and tyramine. The content of histamine was 0.43~10.24 mg/kg while the content of tyramine was 2.11~57.60 mg/kg. As for the physical and chemical indicators, the moisture content in the sample ranged from 13%~23%, the detection range of peroxide value was 0.014 2~0.035 0 g/100 g, with the nitrite content ranging from 2.15 to 7.50 mg/kg.Conclusion:The content of biogenic amines in Hunan bacon products is lower than the European Union and US FDA standard. All physical and chemical indexes meet the national standard.
Abstract: Objective:This study focuses on the effects of twin-screw extrusion on the functional properties and structure of pea protein. Methods: The color change of pea protein extrudates were analyzed by automatic colorimeter, the water holding capacity and emulsifying characteristics of pea protein were analyzed by chemical analysis. The microstructure of pea protein and its extrudates were observed by scanning electron microscope, and the secondary structure of the extrudates were analyzed by Fourier transform infrared spectroscopy. Results: After extrusion treatment, no significant difference was found in the color of pea protein, indicating that the pea protein had a better product color and the water holding capacity was significantly reduced (P＜0.05), with the emulsibility and emulsification stability significantly increased (P＜0.05). Scanning electron microscope showed that the microstructure changed obviously, resulting in protein aggregates with compact structure. The infrared spectrum showed that no new characteristic peaks appeared after extrusion treatment, but the secondary structure conversion occurred; β-sheet and α-helix structure transformed into β-turn and random coil structure, and the structural stability increased. Conclusion: After extrusion treatment, the pea protein retained its original product color, emulsification characteristics were significantly improved, the structure was dense and stability was enhanced.
Abstract: Objective:This study focuses on improving the comprehensive utilization rate of Polygonatum cyrtonema.Methods:The contents of total flavonoids, total saponins and total phenols from roots, stems, leaves, flowers and buds, of P. cyrtonema were determined. The scavenging rates of DPPH·, ·OH and nitrites in extracts of above tissue were measured and compared as well. Results:The contents of total flavonoids and total phenols five different kinds of non-medicinal tissue were in the same order, in which from highest to lowest was, leaves, buds, flowers, stems and roots, and the content of total saponins in flower was the highest In terms of antioxidant activity, the DPPH ·, ·OH and nitrite scavenging rate of leaf extract were the highest, followed by buds and flowers. Correlation analysis showed that the clearance of DPPH ·, · OH and nitrite by the extract from different tissue showed a certain positive correlation with the contents of total flavonoids, total saponins and total phenols. Conclusion:The extract of non-medicinal parts of P. cyrtonema has good biological activity.
Abstract: Objective:A method based on the high resolution mass spectrometry library and diagnostic ratio of characteristic components was established to identify the illegally added psoraleae fructus in wine and tea.Methods:High resolution mass spectrometry library of psoraleae fructus was constructed by high performance liquid chromatography quadrupole time of flight mass spectrometry (HPLC-TOF-MS) for preliminary screening. Combined with the diagnostic ratio method of the characteristic components by, high performance liquid chromatography, psoraleae fructus in different 20 samples of mixed wine and mixed tea from different picking time and origin was tested and analyzed The diagnostic ratio of characteristic component peak area, which was less affected by the origin, picking time and processing technology, has no significant difference between different matrix groups, and was selected as the identification index.Results:High resolution mass spectrometry library of psoraleae fructus was established by high performance liquid chromatography quadrupole time of flight mass spectrometry (HPLC-TOF-MS) for preliminary screening. Corylia/psoralen and psoralen/isopsoralen were selected as the two characteristic groups. The box diagram was drawn to determine that the non-abnormal value range of Corylia/Psoralen was 0.061~0.115, and the non-abnormal value range of Psoralen/Isopsoralen was 1.14~1.68. The established screening and confirmatory methods were validated by commercial samples.Conclusion:The method is simple and efficient, which provides technical support for cracking down on illegal addition of psoraleae fructus in wine and tea.
Abstract: Objective: A microbial enhancer with high-yield glucoamylase was developed from medium-high temperature Daqu and applied to the brewing of Daqu Baijiu for the yield increasing. Methods: Strains with high yield of glucoamylase was isolated from medium-high temperature Daqu and used to make Miqu. Miqu was employed as an enhanced starter in the brewing of Daqu Baijiu, and the yield of Baijiu were tested. Results: A strain M-1 with higher glucoamylase production was isolated and identified as Rhizopus oryzae. The results of the optimized conditions for Miqu making was as follows: bran and rice (2∶8), moisture content 45%, incubation time 72 h, drying temperature 40 ℃. Under the control of these conditions, the glucoamylase activity of Miqu is as high as 864.50 U/g. When appling the Miqu to the brewing of Daqu Baijiu, the results showed that when the addition amount of by, and the yield increased to 43.17% with the addition of 2% (weight of grain) M-1 Miqu. Conclusion: This study established a method for preparing Miqu from Rhizopus oryzae to improve the glucoamylase activity of medium-high temperature Daqu.
Abstract: Objective:In order to established a non-destructive, rapid and efficient method for detecting the moisture content of rice. Methods:This study, 161 rice samples were collected from 5 different regions were studied by near infrared spectroscopy combined with stoichiometry. By eliminating abnormal spectra and preprocessing the spectra, the prediction model of rice moisture content was established by partial least squares regression. Results:15 abnormal spectrum samples were eliminated using the method of principal component analysis combined with mahalanobis distance. The best spectral pretreatment was to eliminate the constant offset. The prediction model R2CAL established in the training set was 0.994 3, root mean square error of calibration (RMSEC) was 0.21%, R2CV was 0.993 6, and root mean square error of cross validation (RMSECV) was 0.32%, which indicated that the cross-validation of the prediction model had high accuracy in predicting sample moisture content. The prediction model was tested with the validation set samples. The validation determination coefficient R2VAL of the model validation set was 0.980 1, the root mean square error of prediction (RMSEP) was 0.36%, and the relative percent deviation (RPD) was 7.14, which indicated that the prediction model had high prediction accuracy for the unknown samples. The P-value (two-sided) of the mean equation T-test of the measured and predicted values of the samples in the validation set was 0.879, and the difference between the measured and predicted values of the samples in the validation set was not significant, indicating that the prediction results of the prediction model were highly reliable. The error between the predicted value and the measured value of the verification set samples was within ±1%, and more than 90% were within ±0.5%. Conclusion:The established rice moisture prediction model can be applied to actual production, and it provides a non-destructive, rapid and high-accuracy detection method for the inspection of rice harvesting and storage.
Abstract: Objective:This study aimed to explore the effect of Pediococcus pentosaceus J8 fermented kiwifruit on bread baking and flavor profile characteristics of wheat bread. Methods: The changes in β glucosidase enzyme activity, organic acids and flavor compounds during kiwifruit fermentation were analyzed. The physical and chemical properties of wheat dough incorporated with fermented kiwifruit were determined. Moreover, the changes in total dietary fiber and total amino acid content, bread quality and flavor characteristics of the resulted bread were also determined. Results: After 15.5 hours of fermentation, the β glucosidase activity reached 55.13 U/L, and the content of lactic acid and acetic acid significantly increased. A total of 110 flavor compounds were detected by GC TOF/MS in kiwifruit. After fermentation, the content of acids, esters, alcohols and terpenes increased, while the content of aldehydes and ketones decreased. For the first time, α angelica lactone, furfuryl acetate and pantolactone were found in kiwifruit. In dough, compared with the unfermented group, the α amylase and protease activities increased by 14.86% and 18.63%, respectively after incorporation of fermented kiwifruit. In bread, compared with the unfermented group, the hardness (11.58%) decreased, while the soluble dietary fiber, total amino acids and specific volume increased by 12.54%, 41.02% and 18.59%, respectively. In addition, bread incorporated with fermented kiwifruit tasted better, had an increased content (27.78%) and type (45.10%) of flavor compounds and a higher overall acceptability than bread incorporated with unfermented kiwifruit. Conclusion: Fermenting kiwifruit with Pediococcus pentosaceuscan improve the flavor and baking characteristics of bread.
Abstract: Objective:Two kinds of titration methods (automatic potentiometric titration and indicator titration) of GB 5009.229 and GB 5009.227 were used to analyze the expanded uncertaintyof the determination of acid value and peroxide value in edible oil.Methods:CNAS-GL006 was used for the uncertainty component and extended uncertainty of the measurement results of the two titration methods.Results:The results showed that the standard solution was the main factor affecting the uncertainty of acid value (value) and peroxide value.Conclusion:The effects of the two titration methods on peroxide value and acid value (value) of edible oil is relatively small, and the appropriate titration method can be selected according to the actual situation for the basic testing organization.
Abstract: Objective: A surface-enhanced Raman spectroscopy (SERS) method was developed for non-targeted screening of PDE-5 inhibitors in health wine. Methods: An appropriate SERS base of colloidal gold was prepared, and SERS analysis was conducted after the base was mixed with 78 kinds of PDE-5 inhibitors. The spectrogram screening database was established, and whether the matching degree was higher than 70% was used as the basis for judging whether the PDE-5 inhibitors were suspected to be added. Finally, the sensitivity and specificity of the method were investigated. Results: The best method of preparing PDE-5 inhibitors of SERS base was adding 1.0 mL 1% chlorauric acid and 0.7 mL 1% trisodium citrate into 98.3 mL ultrapure water. The lowest concentrations were sildenafil 0.05 mg/L, tadanafil 0.5 mg/L, thiosildenafil 0.05 mg/L and acevardenafil 0.1 mg/L, respectively. The qualitative results of simulated samples were consistent with those of HPLC-MS. Conclusion: In theory, this method can be used to screen non-targeted illegal addition of PDE-5 inhibitors in health wine.
Abstract: Objective: A process was developed for the purification of bran polyphenols from HPD 600 macroporous resin. The purity and antioxidant activity of the extracts were analyzed before and after purification, and the polyphenol fractions in the purified products were characterized. Methods: The bound polyphenols in wheat bran were extracted by alkali hydrolysis, and the dynamic adsorption-desorption conditions of the macroporous resin were optimized by single-factor test to determine the optimal purification process. The antioxidant activity fraction was determined by ABTS and DPPH radical scavenging rate. The characterization of the polyphenol fraction in the purified product was completed by UPLC-MS/MS. Results: Under optimal process conditions, the purity of the polyphenols and the antioxidant activity of the purified product were significantly increased. The purified products contained mainly nine polyphenolic compounds, in order of retention time: p-hydroxybenzoic acid, caffeic acid, vanillin, p-coumaric acid, trans-ferulic acid and salicylic acid. Conclusion: The macroporous resin purification process is effective in enriching bran polyphenols and the resulting purified product has a significantly higher antioxidant capacity, while maintaining the richness of the polyphenolic species.
Abstract: Starch and protein are two important components in food system. The interactions between starch and protein have important influence on the structure, physicochemical properties of starch and the texture and digestibility of starch-based food. In recent years, the effect of exogenous protein on starch-protein interaction in mixed system and its application have become a hot research topic in the field of food. This article reviews the interaction mode between starch and protein, the effect of protein on physicochemical properties （gelatinization properties, retrogradation properties, rheological properties, thermal properties and texture properties） and microstructure of starch-protein mixed system, summarizes the regulation effect of protein on digestibility of starch in mixed system and its mechanism, and presents the application of the mixed system in food processing, aiming to clarify the mechanism of interactions between starch and protein and provide theoretical reference for the research and development of starch-based food.
Abstract: Objective:This study aimed to investigate the effects of different concentrations of preservatives on storage quality of orah fruits, so as to reduce the use of preservatives during its planting.Methods:The weight loss rate, vitamin C content, soluble solid content and titratable acid content of fruits were determined under different storage conditions, by using different concentrations of preservative.Results:At 4 ℃ and room temperature, the weight loss rate of fruits treated with preservatives was lower than that of the control group, and preservative treatment had different fresh-keeping effects on orah fruits. At 4 ℃, significant differences in vitamin C content among different treatments at 5, 28 and 42 days of storage were found, but no significant differences in other storage time. No significant difference in soluble solids and titratable acid contents among different treatments appeared. Among the treatment groups (treatment 1, treatment 2 and treatment 3), the weight loss rate, vitamin C content, soluble solid content and titratable acid content of orah fruit in treatment 2 were better than those in treatment 1 and 3. At room temperature, vitamin C content was significantly different among different treatments on the third day of storage. After 14 days of storage, the soluble solid content of treatment groups 1 and 2 was significantly different. On the 14th day of storage time, titratable acid content in treatment group 2 was significantly higher than that in treatment group 3. The contents of vitamin C, soluble solids and titratable acid in treatment group 2 were higher than those in other treatment groups, during most storage time.Conclusion:At 4 ℃, each preservative treatment has different degrees of preservation effect on orah fruits. 450 g/L midazamine +500 g/kg statin +100 g/kg 2,4-D+400 g/kg bellkute has better preservation effect on orah fruit.
Abstract: This review introduced the classification, structure and physical and chemical properties of dietary fiber, and summarized the relevant research literature on the modification methods and physicochemical properties of dietary fiber at home and abroad in recent years. The development direction of the physicochemical properties of dietary fiber and its modification methods were also prospected, in order to provide a theoretical reference for its efficient and comprehensive utilization.
Abstract: Objective: This study aimed to investigate the microbial succession and the changes of volatile flavor substances in traditional fermented fish. Methods: Traditional microbial counting methods, high-throughput sequencing, gas chromatography-mass spectrometry（GC-MS） were applied to explore the effects of different fermentation times of traditional fermented fish （0~180 d） on microflora changes and the volatile flavor compounds during the processing of the solid fermentation process of traditional fermented fish as well as on the correlation between them. Results: The results showed that the main dominant bacterial genera included Staphylococcus, Lactobacillus, etc. That there were 69 volatile flavor components in fermentation process, mainly including acids, alcohols, aldehydes, ketones, N compound；benzene compound, alkyl aromatic compound, esters. and their types and contents changed with the fermentation time. The correlation analysis results showed that Staphylococcus was positively correlated with N-containing compounds and negatively correlated with alcohols. Lactobacillus was significant positively correlated with nonanoic acid,1-octen-3-ol, nonanal, tetradecanal, 2, 4-dimethyl styrene, decyl ene, ethyl caproate （0.01＜P＜0.05）. And negatively correlated with heptenic acid, 3-methylbutyric acid, 2, 3-butanediol, 2, 6-di-tert-butyl p-cresol, Copaene and myristic ethyl ester. Although the relative abundance of microorganisms such as Citrobacter, Turbulella, Psychrobacter, Acinetobacter, Oceanospirillales and Flavobacteria was relatively low in the whole fermentation process, there was also an obvious correlation with the formation of flavor substances. Conclusion: The microbial community and volatile flavor compounds have a series of changes with fermentation time, and there is a significant correlation between them.
Abstract: Objective：This study focused on the antioxidant andimmune enhancing effects of L.bar barumpu ree.Methods：Theantioxidant capacity of L.bar barum puree was measured byes-tab lishing an acute liver injury model.The immune activity of L.bar barum protoplasmwas evaluated by measuring the index ofimmune organs， the content of serum hemolysin and the degreeof plantar thickening.Results：Both low and medium doses of L.bar barum puree could significantly increase the content of glut a-thione peroxidase(GSH PX) in serum(P＜0.05， P＜0.01) andglutathione(GSH) in liver tissue(P＜0.05) ， and significantlydecrease the content ofprotein carbonyl in liver tissue ofmicewith acute alcoholic liver injury(P＜0.05， P＜0.01)andthecontent of malondialdehyde(MDA) (P＜0.05， P＜0.01) ， andthis indicate L.bar barum protoplasm hadantioxid antact ivity.After continuous gavage of L.barbarum protoplasm for 45 days，the organ development of normalm icewasn otaffected.Compared to the untreated mice， the content of serum hemolysin(P＜0.01)and the degree of foot thickening(P＜0.05)andphagocytosis index(P＜0.01) increased significantly， indicatingthat L.bar barum puree could enhance mice immunity.Conclusion：Eating a certain dose of L.bar barum puree can en-hance the antioxidant capacity and immune ability.
Abstract: Based on the scientific theory of modern nutrition and functional food science, this paper uses biotechnology and information digital technology to establish a more precise, flexible, integrated and digital functional food research and development system-flexible precise nutrition intervention system (FPNIS) which improves the shortcomings of the two common functional food research and development models that are based on traditional Chinese herbal medicines or simple ingredient dietary supplements. Through the establishment of FPNIS, provide a new way to explore the research and development of efficient and precise functional food, and analyze its trend.
Abstract: Almond oil is a functional vegetable oil obtained from apricot kernel by pressing, extracting and other technologies, which has the effects of anti-oxidation, anti-inflammation, anti-tumor and prevention of cardiovascular diseases. In this review, the extraction process, nutritional composition and health effect of almond oil were summarized, and the future development tendency of almond oil was prospected.
Abstract: Objective:This study aimed to establish a new method for the determination of matrine and oxymatrine in honey by UPLC-MS/MS. Methods: The honey was dissolved in water, and the liquid-liquid extraction pretreatment technology was adopted. The extraction was achieved using ammonia-acetonitrile, with the addition of sodium sulfate to induce a salting out effect. Chromatographic separation was achieved on Inspire HILIC column in the mobile phase composition of acetonitrile and 0.1% formic acid5 mmol/L ammonium acetate buffer. Mass Spectrometry was carried out under the multiple reaction monitoring (MRM) mode with positive electrospray ionization (ESI+) and external standard method for quantitative analysis. Results: The linear relationship between matrine and oxymatrine was observed in the range of 1~100 ng/mL, with correlation coefficients higher than 0.998. The detection limit and quantitative limit of matrine and oxymatrine in honeywere 0.1 μg/kg and 0.3 μg/kg, respectively. The average recoveries of matrine and oxymatrine were 90.9%~95.1% and 80.9%~84.3%, respectively, at the spiked levels of 1, 10 and 100 μg/kg, with the relative standard deviations (RSDS)＜ 10% (n=6). The validated method was then successfully applied to the determination of matrine and oxymatrine in 45 commercially available honey, and the results showed that the detection probability and content of matrine and oxymatrine in acacia honey were relatively high. Conclusion: The established method is accurate, rapid, and sensitive, Moreover, a simultaneous preparation of multiple sample extracts is available, and it can used for the routine determination of matrine and oxymatrine in honey.
Abstract: Objective: To accurately distinguish intact peanut, nut damaged peanut and epidermis damaged peanut. Methods: A peanut seed integrity detection scheme based on deep learning convolution neural network (CNN) was proposed. The peanut seed color selection system was established and a peanut seed image database was also established; The improved density peak clustering (DPC) algorithm was used to adaptively compress the CNN convolution kernel to effectively balance the network depth and operation efficiency; The improved sparrow search algorithm was used to optimize the CNN super parameter configuration and network structure, and the CNN model suitable for peanut grain integrity detection was obtained. Results: Compared with other detection methods, this scheme improved the recognition accuracy by about 5.41%~13.92%, and the detection time of single image of peanut grain was shortened by about 16.9%. Conclusion: This method effectively improves the accuracy and real-time of peanut grain integrity detection.
Abstract: The new extraction technologies of citrus flavonoids in recent five years were reviewed, including low eutectic solvent extraction, subcritical fluid extraction and magnetic molecular blot selective extraction.the bioactivities and mechanisms of citrus flavonoids, such as antioxidant, anti-inflammatory, antibacterial, anti-obesity, anti-diabetes, anti-cancer, intestinal protection, cardiovascular protection, liver protection and neuroprotection, were also expounded, and suggestions for further study of citrus flavonoids were proposed.
Abstract: Objective:Improve the quality of dried okra products.Methods:The rehydration ratio, shrinkage rate, vitamin C content, drying time and sensory score were used to analyze the effects of different pretreatment methods on the quality of dried okra products, and the coefficient of variation method was used for comprehensive weighted evaluation.Results:The results showed that blanching and ultrasonic pretreatment can significantly increase the rehydration ratio of the dried sample (P＜0.05). The shrinkage rate was most affected by blanching. The vitamin C content of the pretreatment group was lower than that of the control group, and the ultrasound treatment group had the least loss. The blanching and ultrasonic pretreatment can shorten the drying time, and sensory scores of samples pretreated by ultrasound and color protection were significantly higher than those pretreated by blanching (P＜0.05). The comprehensive evaluation by the coefficient of variation method showed that the quality of the okra pretreated by ultrasonic was the best, followed by the color protection treatment, and the blanching treatment had the lowest comprehensive score. When the ultrasonic pretreatment temperature was 20 ℃, the comprehensive score of the dried sample obtained was the highest, which was 0.907.Conclusion:The research showed that the ultrasonic pretreatment was a better pretreatment method with hot air drying of okra.
Abstract: Objective: The adsorption performance and mechanism of Xanthoceras sorbifolia shell biochar activated by phosphoric acid for methylene blue was investigated in this study. Methods: With phosphoric acid as activator, the Box-Behnken center combination design was used to optimize the preparation conditions of biochar from Xanthoceras sorbifolia shell. The biochar obtained under the optimal preparation conditions was used to adsorb methylene blue in water. Through investigating the adsorption influencing factors, the adsorption characteristics of biochar on methylene blue were determined, and combined with the analysis of kinetic, the adsorption mechanism was discussed. Results: The optimum technological conditions for preparing biochar from Xanthoceras sorbifolia pericarp by phosphoric acid activation were as follows: impregnation ratio （mPericarp powder∶mPhosphoric acid solution） 1∶21, pyrolysis temperature 530 ℃ and pyrolysis time 75 min. The optimal conditions for adsorption of methylene blue in water by sorbent biochar from Xanthoceras sorbifolia shell are as follows: initial pH of solution 12.6, dosage of biochar 1.0 g/L, initial mass concentration of methylene blue 200 mg/L, and adsorption equilibrium time 120 min. The adsorption of Xanthoceras sorbifolia shell biochar on methylene blue in water obeys the quasi second order reaction kinetics. The adsorption process consists of three stages: liquid film diffusion control, pore diffusion control and adsorption desorption equilibrium. Conclusion: Phosphoric acid activation can significantly increase the specific surface area and pore volume of sorbent biochar from Xanthoceras sorbifolia sheell, thereby significantly improving its adsorption capacity for methylene blue.
Abstract: Objective：This study aimed to clarify the content anddistribution of polyphenols in fruit juice samples and explore theintrinsic connection of the content of polyphenols with the taste offruit juice .Methods： 15 kinds of polyphenols in fruit juice sampleswere determined by HPLC-MS/MS following ethanol ultrasonic-assisted extraction.Various statistical methods such as correlation and_cluster analysis，were used to establish thesensory evaluation system of fruit juice with the values ofdifferent tastes，including sweetness，sourness，bitterness，salty， umami， astringency and piquancy.Lastly， the relationshipbetween the content of polyphenols and sensory evaluation wasexplored by correlation analysis .Results： 14 types of fruit juiceswere divided into four categories owing to their taste， namelysweet， sour-sweet， bitter and bitter-astringent.There was sign if-icant positive relationship between the content of total polyp he-nols， phenolic acids， flavonoids， chl orogenic acids， free phenolicacids and value of astringency.Conclusion：Thecontentsofpoly-phenol varied greatly in different fruit juices， and those withbitter and astringent taste often had high content of polyphenol.However， those with sweet taste had low content of poly oh enol.Polyphenolic compounds， especially the free phenolic acids werethe key substances affecting taste of astringency of fruit juice.
Abstract: Objective:A method based on the high resolution mass spectrometry library and diagnostic ratio of characteristic components was established to identify the illegally added psoraleae fructus in wine and tea.Methods:High resolution mass spectrometry library of psoraleae fructus was constructed by high performance liquid chromatography quadrupole time of flight mass spectrometry (HPLC-TOF-MS) for preliminary screening. Combined with the diagnostic ratio method of the characteristic components by, high performance liquid chromatography, psoraleae fructus in different 20 samples of mixed wine and mixed tea from different picking time and origin was tested and analyzed The diagnostic ratio of characteristic component peak area, which was less affected by the origin, picking time and processing technology, has no significant difference between different matrix groups, and was selected as the identification index.Results:High resolution mass spectrometry library of psoraleae fructus was established by high performance liquid chromatography quadrupole time of flight mass spectrometry (HPLC-TOF-MS) for preliminary screening. Corylia/psoralen and psoralen/isopsoralen were selected as the two characteristic groups. The box diagram was drawn to determine that the non-abnormal value range of Corylia/Psoralen was 0.061~0.115, and the non-abnormal value range of Psoralen/Isopsoralen was 1.14~1.68. The established screening and confirmatory methods were validated by commercial samples.Conclusion:The method is simple and efficient, which provides technical support for cracking down on illegal addition of psoraleae fructus in wine and tea.
Abstract: In order to study the factors that the influence of the cassava stalk toughness. Orthogonal experiments were used to test cassava stalk with MW-4 universal testing machine And the influencing factors were selected, for cassava stalk variety, placed time, and colliding parts. The results show that: effect of varieties on the impact energy is the largest, while, the impact energy was the smallest when the variety is SC6, placed for 12 days, and the the upper part collision site. Effect of varieties A on the impact toughness is the largest. The impact toughness is the smallest when the variety is SC6, the moisture content is placed for 0 days, and lower part collision position. The average impact energy and impact toughness of the lower part of cassava stalk are higher than the upper part.
Abstract: Introduces a electrostatic potential test system designed by LabVIEW, which had been done 7 electrostatic potential test experiments for 6 factors of electrostatic potential on the surface of electrostatic stalk extractors frictional roller, and improve overall electrostatic potential of the optimal solution is given. When drum material is synthetic rubber, roller rotation speed is 38 r/min, counter weight is 10.5 kg, friction material is silk, the humidity is controlled below 60%, the overall electrostatic potential and the stalk rate is the highest.
Abstract: There were two methods to detect the plasticizers of red wine. The first one was a traditional method(GC-MS) and another one was a new method-ELISA kit. An improved pre-processing of GC-MS and the comparative analysis of the two methods was used to find a novel detection method. The results: there was a little difference for the rate of plasticizer extraction with different pre-treatment. And DIBP, DBP, DEHP were detected. The GC-MS method demonstrated high precision and recovery. The GC-MS method was a excellent method to detect the plasticizers of red wine. The detection results of ELISA kit were 3.4 to 5.5 times larger than the GC-MS method. It was enough for ELISA kit as a rapid detection method of the plasticizers of red wine.
Abstract: A method was developed using ICP-AES for the simultaneous determination on the content of trace heavy metals including Na, Mg, Al, K, etc in 3 spieces of jujube of Xin Jiang district. The correlation index of method was greater than 0.998; Determination of elements in addition to the individual value, RSD is less than 5%. The results showed that: xinjiang jujube had rich mineral elements content, which especially in K (＞12 277 μg/g), Ca (＞785 μg/g), Mg (＞ 646 μg/g), Na (425 μg/g), Al (＞179 μg/g), Fe (＞22 μg/g) content is higher, the K and Fe content of Aksu jun jujube and Hami jujube were higher than other areas and varieties of jujube.
Abstract: The sample was purifid by solid phase extraction column. A simple, fast, accurate method for determination of Imibenconazole in fruits and vegetables was developed by ultra high performance liquid chromatography-tandem quadrupole mass spectrometry (UPLC—MS—MS). The linear range of the method is from 1.0 μg/L to 100 μg/L ，and the correlation coefficients were 0.998 7～0.999 6, and the detection limit is 1.0 μg/kg. The proposed method has high sensitivity and good reproducibility for determining Imibenconazole.
Abstract: The reasonability using near-infrared spectra (NIRS) for detection of melamine in liquid milk were studied. NIRS of samples were obtained by Fourier Transform Infrared Spectroscopy(FTIR) spectrometer, samples of liquid milk with adding melamine were analyzed while characteristic signals were extracted by wavelet transform and principal component analysis. Quantitative analysis was taken by General the Regression Neural Network(GRNN) for the diffuse reflectance spectroscopy of liquid milk adding melamine first. The result is not satisfactory enough that when concentration of melamine is lower than 0.05%, the R2 of predict model is only 0.567. Qualitative discrimination by support vector machine was carried out later. The results showed that the model has a very good discriminate ability of the spectrum. The accuracy of the test set was 94.44%. Overall, NIRS combined with appropriate chemometrics methods is a feasible way to take qualitative discrimination of liquid milk whether or not adding melamine.
Abstract: The unsafe factors in the products of traditional craft baked betel nuts, betel improved oven baked dry and edible betel nut pieces were analyzed. The results showed that benzopyrene were the major effect factors on the food safety of Betel nut products. And the baked methods of betel nuts had greatly influence on the content of benzopyren. An overdose of benzopyrene was found in these baked betel nuts baked by traditional ways, such as traditional smoked roasting ovens, traditional hot wind roasting ovens. However, taking the baked Betel nuts as materials to manufacture products, the content of benzopyrene in these was within the safe limit level. Sulfur dioxide and nitrite was detected in commodity betel, but it's content within the relevant national control standards, and not enough to cause food safety problems.
Abstract: Recently，the beef and mutton industrialization is developing rapidlyin Xilingol district of Inner Mongolia. To have a better understanding of sanitary quality of Xilingol beef and mutton, tests of bacterial colony, fecal coliform and pathogenic bacteria were conducted on 160 pieces of Xilingol beef and mutton samples. The results showed that the qualified rate of bacterial colony and fecal coliform were 76.25% and 77.18%, and the detection rate of pathogenic bacteria was 5.63%. The data provided theory evidence for improving Xilingol beef and mutton sanitary quality in the future.
Abstract: To investigate the accumulation and pollution in Zn, Cu, Pb and Cd of the leaf vegetable by Changsha section of Xiangjiang River, three kinds of vegetable were collected and detected. The results showed that: the contents of these four heavy-metal elements in vegetable samples ranked from greatest to least was as follows: Zn＞Cu＞Pb＞Cd; Brassica chinensis L. had strong accumulation ability in Cu, Pb and Cd; 26.67% samples were heavy contaminated.
Abstract: To investigate the distribution of serotypes, genetic relativity and epidemiological characteristic of Listeria monocytogenes (LM). 22 LM strains isolated from Guangzhou and Xiamen were investigated by ERIC-PCR and Sau-PCR. Results of ERIC-PCR showed that these strains were distributed in 8 patterns (a-h). The main pattern was pattern h, and the number of strains was 8. Genotyping using Sau-PCR showed that all tested strains were grouped into 7 clusters (A-G). These results indicated the genetic relativity and epidemiological characteristic of different LM food-borne isolates.
Abstract: This research according to the quality requirements of massage base oil as evaluation indexes, combining with free radical clearance, oxidation resistance and other indicators, compared the decolorizing technology's influence on the quality of sesame oil. And compare oils which have done in-depth research in the field of cosmetic skin care, such as olive oil, grape seed oil, wheat germ oil. That results showed that the decoloring process of sesame oil improve the oxidation resistance and the ability of scavenging free radicals significantly. In general, sesame oil skin care is better than other several kinds of vegetable oil which used as massage base oil commonly.
Abstract: The best adsorption conditions of the attapulgite on Lactobacillus cells were optimized. Different kinds and concentrations of acids and alkalis were used to pretreat the attapulgite, the results showed that 1 mol/L H3PO4 was the best. In pH 6, 0.4 mol/L phosphate buffer system, adsorption of attapulgite on Lactobacillus cells basically completed in 60 min, and reached to the adsorption equilibrium. Adsorption of attapulgite on Lactobacillus cells could well fit the Langmuir adsorption isotherm equation. With the increase of temperature, the equilibrium adsorption of attapulgite on Lactobacillus cells increased higher, which was an endothermic process. When Lactobacillus cells concentration increases, the equilibrium adsorption capacity was also increasing. The adsorption process belonged to the preferential adsorption.
Abstract: The physical properties test of the crunchy rice candy was carried out with a texture analyzer under compression mode. The crispness of the crunchy rice candy was tested using the sensory evaluation method and was adopted the compression mode a texture analyzer. Spss statistical analysis software was applied to the data of crispness sensory eveluation and texture test. Subsequently, the forecast model was constructed for the crunchy rice candy crispness by analyzing the correlation between the data of crispness sensory eveluation and texture test. The results showed that:the best testing speed was 1.0 mm/s, the compression deform deformation was 50%.The Peak Positive Force（X1）, Positive Area（X2）,Area To Positive Peak（X3）, Linear Distance（X4）data were very significantly correlated with the crispness of the crunchy rice candy. The prediction model was Y=-4.130+0.241X1-0.101X2-0.487X3+0.128X4, the correlation coefficient was 0.977, P＜0.05, and the model can predict the crispness of the crunchy rice candy.
Abstract: The changes of microstructure of cooked chicken breast treated by ultra-high pressure treatment(UHP) were observed, for the further study of UHP on cooked chicken breast. Results indicated that the gap between the muscle fibers decreased, endomysial disappeared gradually, and the structure of muscle fibers was more closely. Meanwhile, muscle fiber diameter and rate of juice leakage increase could be resulted from UHP significantly. Myofibril was fragmented and gelated obviously when the pressure was over 400 MPa. The microstructure of cooked chicken breast treated by UHP could explain the changes of jucie leakage, texture and edible quality.
Abstract: Chicken was cooked by three methods which were frying, braising and stewing, to compare the changes of volatile aroma and texture of cooking chicken. Results showed that after cooking chicken sensory quality characteristics changed dramatically. Aldehydes content was significantly higher than alcohols and alkanes in volatile components of fresh meat. However, the volatile compositions of cooking chicken were mainly aldehydes and alkane substances, and aldehydes and alcohols content decreased significantly, with the order of decreasing degree: fried > braised >stewed; But alkane matter content increased significantly with the same order of increasing degree as above. After cooking, some new macromolecules were detected too. Of the three cooking ways, the hardness and chewiness of fried chicken were the lowest, but elasticity and cohesiveness were the highest; the hardness and chewiness of braised chicken tended to be the highest, but elasticity and cohesiveness were the lowest.
Abstract: The nutrient compositions’ change of green beans, black beans, soybean were studied during sprouting in order to provide experimental basis for the sprouting soybean food production and processing. Control soybean germination conditions by using a certain temperature and humidity, regular sampling and assay sprouted soybean’s crude protein, crude fat, reducing sugar, Vc and isoflavone’s content. The results show that: the protein content of green beans, soybean and black beans after seven days’ germination increased by 24.03%, 24.28% and 22.88% respectively than after one day’s germination, the reducing sugar content increased by 129.06%, 127.17% and 125.73% respectively; the Vc content increased by 831.37%, 663.97% and 807.07%; the crude fat content reduced by 37.28%, 35.68.28% and 36.69% respectively. The isoflavone content of three kinds of soybeans reached the maximum value after four days’ germination, the black soybean’s isoflavone was 0.531% and was the highest.
Abstract: The pH value, intermediate (A294nm), browning intensity (A420nm), free amino group content and antioxidant activity as detection index. The effect of temperature(100 ℃, 120 ℃) on Maillard reaction and antioxidant activity of the Maillard reaction products(MRPs) derived from yellow stripe trevally(Selaroides leptolepis) fish protein hydrolysates was investigated. The results were as follows: when reaction temperature was 120 ℃, the pH value, intermediate (A294nm), browning intensity (A420nm) and free amino group content of the systems during the Maillard reaction were more significant, and the reducing power and DPPH radical scavenging activity of MRPs were enhanced greatly, however, the hydroxyl radical scavenging activity and Fe2+ chelating activity of MRPs were decreased significantly, compared with 100 ℃.
Abstract: Releasing regular of flavor compounds during enzymolysis of mussel (Mytilus edulis) protein and the structure of seafood flavor peptides were investigated with amino acid analysis, ultrafiltration, gelchromatography, RP—HPLC, and UHR—Q—TOF. The results indicated that, during enzymolysis, molecular weight of peptides reduced. The amount of free flavor amino acid and TMA increased. The amount of peptidyl flavor amino acids increased then decreased. It’s advantageous for peptides with low molecular weight to be released at low pH conditions. The total carbohydrate varied little. The total acid reached the maximum in 1 h and at 50℃, respectively. Under the conditions that enzymolysis time of 2 h, enzymolysis temperature of 50 ℃ and enzymolysis pH of 6.5, the percentage of low molecular weight peptides, total acid, total carbohydrate, and flavor amino acid were in fairly high level. The flavor peptides form mussel (Mytilus edulis) were determinated as peptides in a low molecular weight below 1 kDa, with unique amino acid sequences of Cys-Ser-Val-Gln-Asp-Gln or Gln-Ala-Val-Asn-Phe-Thr, and taste threshold of 0.1 mg/mL.
Abstract: Chicken soup and mixed samples with artificial blending were tested by electronic tongue and the response signals were analyzed by principal component analysis (PCA), discriminant factor analysis (DFA) and partial least-squares analysis (PLS). Chicken soup and artificial blended soup were successfully identified by electronic tongue. Moreover, a high regression coefficient, R2=0.958 71, between instrumental response signal and mixed ratio of chicken soup and artificial blended soup was found for the established PLS model with a prediction error below 15%.This study demonstrates that electronic tongue is applicable for soup discrimination.
Abstract: Effect of the different ratio of succinic acid to cigarettes on the volatile substances formed in the process of pyrolysis was studied to investigate the influence mechamism of succinic acid on the decreasing flavor of cigarettes by the technologies of online Pyrolysis-Gas Chromatography/Mass Spectrometry. It was shown that free nicotine would decrease substancially while mono-protonated and diprotonated nicotine would increase obviously with increasing succinic acid. With the addition of 1%, 2% and 3% of succinic acid to cigarettes, the total volatile substances formed in the process of pyrolysis of cigarettes was reduced by about 23 percent, while low molecular weight carbonyls and furans down by 26%～30% and alkenes down by 23%～26%. The quantity of carbohydrates pyrolysates and volatile Maillard reaction’s products fell by 30 percent, particularly DDMP and 5-hydroxymethyl furfural decreased sharply, down by 84.1% and 75.6% respectively when the usage of succinic acid reached 3%. The total phenols were reduced by 29.5%, 37.0% and 37.3% respectively while key aroma chemicals fell by 31.4%, 36.8% and 36.8% respectively, when 1%, 2% and 3% of succinic acid were added to cigarettes. According to the changing conditions of the formed volatile substances, the influence mechanism of succinic acid on the suppressing flavor of cigarettes was deduced.
期刊介绍
Editor-in-Chief：ZHU Bei-wei
Address：Changsha University of Science and Techonology NO.960 2nd section, Wanjiali RD(S)
