Abstract:Objective:This study aimed to classify the mechanism of pullulanase-catalyzed hydrolysis of waxy rice starch under electric field treatment, by monitoring the changes in hydrolysis efficiency, pullulanase activity, and the structure and properties of waxy rice starch. Methods:The hydrolysis efficiency was determined, and the structure and thermal properties of hydrolysates were characterized, by using scanning electron microscope, X-ray diffractometer, differential scanning calorimeterand rapid viscosity analyzer. Results:Under the control of the following conditions, electric field with intensities ≤2.5 V/cm could increase pullulanase activity, accelerate the hydrolysis, induce the pores and cracks on the granule surface, increase the relative crystallinity, increase the gelatinization temperature and reduce the pasting viscosity of waxy rice starch. However, electric field with intensities ≥5 V/cm could cause the partial inactivation of pullulanase and reduce the hydrolysis efficiency, and consequently caused less change of the relative crystallinity and pasting viscosity. Conclusion:The strengthening effect of the electric field treatment on pullulanase hydrolysis of waxy rice starch mainly affected pullulanase activity, but has no significant effect on the structure of starch.

Abstract:Objective:This study aimed to solve the problems of time consuming and high cost in the natural aging process. Methods: Black rice wine was treated with different microwave power, time and temperature. The contents of main phenols, organic acids, and esters in black rice wine treated by microwave technology were analyzed. Results: Microwave treatment could increase the contents of total esters, protocatechuic acid, gallic acid, syringic acid, acetic acid, ethyl valerate and ethyl acetate, reduce the contents of total phenols, total acids, caffeic acid, citric acid, tartaric acid, lactic acid and ethyl lactate, and have little effect on the contents of oxalic acid and malic acid. Conclusion: Three kinds of black rice wine with similar substance change trend to the natural aging can be produced in a short time, by using microwave treatment at 100 W, 40 ℃, for 3 min or 6 min.

Abstract:Objective:The effect of dried silver carp process on quality and safety was studied. Methods: Taking the fresh silver carp as the raw material, the curing concentration (NaCl), curing temperature, curing time, drying temperature and drying time as investigating factors, investigated the effects of different processing conditions on the rehydration rate, color, texture and AGEs formation. Results: The concentration of curing salt and drying temperature had significant effects on the sensory evaluation of dried fish products (P＜0.05), and the optimal processing conditions obtained were curing concentration of 9%, curing temperature of 4 ℃, curing time of 3 h, drying temperature of 60 ℃ and drying time of 24 h. The alkanes, aromatic compounds and sulfur-containing organic compounds contributed most to the flavor of dried fish. The dried fish products with a curing concentration of 9%, curing temperature of 4 ℃, curing time of 3 h, and drying temperature of 60 ℃ had better retention of flavor substances. The samples became yellowish in color, less bright and harder, which was reflected in sensory changes as dried fish products with golden color, firm texture and non-flabby tissue. The content of carboxymethyl lysine (CML) and carboxyethyl lysine (CEL) increased with increasing salt content. However, the differences in CML and CEL of dried fish under 3% and 9% salt concentration curing were not significant. Conclusion: The dried fish products with curing concentration of 9%, curing temperature of 4 ℃, curing time of 3 h, drying temperature of 60 ℃ and drying time of 24 h are the optimal products. This study provides technical support for the processing and safety control of dried silver carp.

Abstract:Objective:In order to realize the detection of apple sugar content, a nondestructive prediction method of apple sugar content based on the characteristic gray series of apple reflection spot image in darkroom system is proposed. Methods:The laser with the peak wavelength of 670 nm absorbed by the apple was used as the illumination light source, which was incident from the illumination port of the integrating sphere. The apple sample was placed at the sample port of the integrating sphere, and the reflection spot of the apple sample was obtained at the measuring port of the integrating sphere. Through the image collected by mobile phone, the gray information of the reflection spot image of apple under the irradiation of this wavelength was studied. It was found that the gray distribution of the reflection spot image of apple with different sugar content was different. Using partial least squares (PLS) algorithm, for 90 samples of three apple species in the training set, taking the pixel frequency (i.e. characteristic Gray Series) with gray value between 90~110 in the outer ring area of the reflected spot image as the sugar content related component, the three apple species were modeled and predicted respectively, so as to realize the nondestructive and rapid measurement of apple sugar content. Results:The predictive correlation coefficients of three kinds of apples in the training set were 0.89, 0.84 and 0.94 respectively. Based on the designed three kinds of apple sugar content prediction model, another 60 samples of the three apple species are verified. The prediction correlation coefficients of the three corresponding kinds of apple sugar degree in the verification set can reach 0.70, 0.73 and 0.76 respectively. Conclusion:Compared with the method of using multi wavelength fusion to predict apple sugar content, using a single strong absorption wavelength and the characteristic gray series of apple reflection spot image in darkroom system can be used as the basis of apple sugar content prediction, which provides a new research idea for apple sugar content prediction.

Abstract:Objective: To study the effects of microbial nitrification inhibitors on the formation and changes of flavors in air-dried sausages. Methods: Four groups of air-dried sausages were designed: MNI group: 0.05% of microbial nitrosation inhibitors (MNI) were added; MNIP group: 0.05% MNI and an inoculation of PRO-MIX5 commercial starter (Staphylococcus xylose, Lactobacillus sake,and L. plantarum) were added; FBFAP group: fermented beef flavorings and compound antioxidants were added, and the sausages were inoculated with the PRO-MIX5 commercial starter; and CK group: blank control (CK). The flavor of air-dried sausages was determined by an amino acid analyzer, Heracles iii ultra-fast gas phase electronic nose, electronic tongue and gas chromatography-mass spectrometry (GC-MS). Results: Glutamate, alanine, taurine and carnosine are the primary free amino acids in the four groups of air-dried sausages. The addition of MNIP promoted the production of fresh amino acids and increased the total amount of free amino acids. Glutamate and alanine, two umami and sweet amino acids, contributed the most to the taste of air-dried sausages, and the four groups of air-dried sausages were primarily umami and sweet. There were differences in flavor and taste among the four groups. The electronic nose and electronic tongue principal component analysis (PCA) could distinguish between them. The flavors and taste of the MNI and MNIP groups were similar, and the taste of FBFAP group and CK were similar. The addition of MNI and MNIP improved the umami of air-dried sausage and reduced its saltiness and bitterness. Ethyl hexanoate and ethyl isovalerate were the characteristic flavors of the MNIP group. Linalool was the characteristic flavor of the MNI group, while decanal and ethyl isovalerate were the characteristic flavors of the FBFAP group. Conclusion: The addition of MNI alone or the synergistic effect of MNI and PRO-MIX5 promotes the formation of flavor in the air-dried sausages, indicating that MNI shows great promise at promoting the formation of flavor in air-dried sausages.

Abstract:Objective: This study aimed to obtain the volatile components of different parts of lavender in natural condition and provide theoretical basis for quality evaluation and rational utilization of lavender varieties.Methods: Orthogonal experiment was used to optimize the headspace solid phase microextraction (HS-SPME-GC-MS) conditions, and the volatile components of the root, stem, leaf and flower of the representative lavender species France blue were analyzed under the optimal conditions.Results: The optimal conditions of HS-SPME were extraction time 60 min, equilibrium time 20 min and desorption time 5 min. Under the control of these conditions, a total of 36 chemical components were identified from different parts of lavender, among which 6 compounds were identified from each part.Conclusion: The content of volatile components in different parts of lavender varies greatly, among which the content of volatile components in flower parts is higher than that in leaf, and the content of volatile components in stem and root is the least. The contents of ester compounds in flowers and stems were prominent. The contents of olefin in roots and leaves were more prominent.

Abstract:Objective: To investigate the effect of moisture content of heated cigarette on releases of aerosol main components. Methods: Three different types of heated cigarettes were used to study the effects of moisture content of cigarette sticks on the release of main aerosol components by gas chromatography. Results: ① The equilibrium humidity was a positive correlation between the moisture contents of tobacco materials and releases of total aerosol particulate matters. ② The moisture contents of heated cigarettes stored at different equilibrium humilities had a great effect on releases of glycerol and nicotine in aerosol, but a small effect on release of propylene glycol. ③ The release of nicotine in aerosols increased first and then decreased with the increase of equilibrium humidity, and release of nicotine in aerosol was the highest after heated cigarette stored at 50% relative humidity. Conclusion: The water content of three kinds of heated cigarette tobacco materials has influence on the release amount of total aerosol particles, smoke agent and nicotine.

Abstract:Objective: The study aimed to develop the vegetable value of common vetch (CV) and explore the effects of salt solution on phenolic accumulation and antioxidant activity in CV sprouts.Methods: The effects of NaCl stress and supplemental CaCl2 on free and combined phenolic accumulation in CV sprouts were analysed by UPLC in comparison with pea sprouts, soybean sprouts and mung bean sprouts. The changes of key enzyme activities and gene relative expression levels of PAL, C4H and 4CL, antioxidant enzyme activities and antioxidant activities were investigated under NaCl and CaCl2 treatments.Results: The total phenolics increased from (10.63±0.40) mg GAE/g DW to (15.76±0.36) mg GAE/g DW with the co-treatment of NaCl and CaCl2. Sixteen phenolic acids were detected in CV sprouts. The content of Rutin increased from (22.50±0.49) mg/kg DW to (57.38± 0.87) mg/kg DW with the co-treatment, which was 79.69, 260.82, 5.89 times of pea sprout, soybea sprout and mung bean sprout respectively. Na+ increased enzyme activities of PAL,4CL and C4H by increasing their relative gene expression levels. However, the co-treatment increased enzyme activities but their relative gene expression levels decreased or didn?t change significantly.Conclusion: The co-treatment of NaCl and CaCl2 can enrich the phenolic content and enhance its antioxidant activity of CV sprouts.

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: A rapid method for determination of bongkrekic acid in Auricularia auricular was developed using QuEChERS in combination with UHPLC-MS/MS. Methods: In this study, Several important experimental parameters, including type of extraction solvent, extraction time, adsorbent type and adsorbent dosage were effectively optimized using spiked samples. The sample were shaken with methanol containing 1% ammonia water, and then carried out by the C18 adsorbent purification.Results: The bongkrekic acid was determined within 4 minutes by negative ion multiple reaction monitoring mode analysis and external standard method. The linear range was 0.05~10.00 ng/mL (r＞0.998 3). The limit of detection (LOD) was 2 μg/kg, respectively. The average recovery rate at different levels(low, medium and high) the intra-batch (n=6) was 74.4%~91.6%, the inter-batch (n=3) were 74.9%~89.4% with a RSD ranging from 3.3%~9.2%.Conclusion: The developed method shows simple, rapid, excellent recovery and stable repeatability, and the limit of detection lower than the existing detection standards. It is suitable for the effective detection of bongkrekic acid in Auricularia auricular samples.

Abstract:Objective:This study aimed to effectively improve the risk warning and quality and safety supervision of polycyclic aromatic hydrocarbons (PAHs) in spicy strip.Methods: The target compounds in the samples were extracted with acetonitrile and purified by QuEChERS, containing 100 mg N-propyl ethylenediamine (PSA), 100 mg octadecylsilane bonded silica gel (C18), and 1 000 mg neutral alumina adsorbent, and then were separated by DB-EUPAH column. It was detected by gas chromatography-triple quadrupole mass spectrometer with multiple reaction monitoring mode and matrix matching external standard method.Results: The 16 kinds of PAHs showed good linearity in the range of 0.005~0.500 μg/mL, and the correlation coefficients were 0.998 4~0.999 9. The limits of detection and quantification were 0.04~0.55 μg/kg and 0.12~1.85 μg/kg, respectively. The average recoveries of 16 kinds of PAHs were 71.54%~103.70% with the relative standard deviations of 2.4%~9.3% at three-level spiked standard sample of 10, 20 and 100 μg/kg. The method was used to analyze the contamination of 16 kinds of PAHs in 20 batches of spicy strip. PAHs were detected in 14 batches with the content ranging from 0.42 μg/kg to 42.28 μg/kg.Conclusion: The method is easy to operate with high sensitivity, and suitable for daily detection of 16 kinds of PAHs in spicy strip.

Abstract:Objective: A high performance liquid chromatography method was established for determination of four artificial sweeteners in syrups, i.e., acesulfame, saccharin sodium, aspartame and advantame.Methods:Acetonitrile was used as mobile phase A, and 0.02 mol/L ammonium dihydrogen phosphate (pH value adjusted to 5.5 by triethylamine) was used as mobile phase B. The gradient elution was conducted, with flow rate at 1.0 mL/min,and the column temperature was at 35 ℃; the detection wavelength was 214 nm, and sample size was 10 μL was loaded on the was Shiseido AQ-C18 column (4.6 mm×250 mm, 5 μm) A total of 45 batches of children's cough syrup samples from 21 manufacturers were determined by the established method.Results:The linear calibration curve of the four kinds of artificial sweeteners were obtained over the range of 2~100 mg/L. The average recoveries of acesulfame, saccharin sodium, aspartame and advantame were 98.65%, 104.09%, 100.96% and 102.30% respectively, with RSDs less than 2% (n=9). The actual sample test results showed that 3 batches of samples were found to be advename, and 2 batches of samples were found to be aspartame and advename.Conclusion:The established method is specific, simple, and reliable, and can be used to monitor the illegal addition of artificial sweeteners in syrups.

Abstract:Objective: Uncertainty assessment of the content of synthetic capsaicin, natural capsaicin and dihydrocapsaicin in edible oils and fats by liquid chromatography-mass spectrometry was carried out, and the sources of uncertainty and the key factors affecting the test results were analyzed, so as to improve the accuracy of test results.Methods: To establish a mathematical model for the uncertainty of the content of synthetic capsaicin, natural capsaicin and dihydrocapsaicin in edible oils and fats, to analyze the factors that may introduce uncertainty in the detection process, and to evaluate each uncertainty component.Results: The contents of synthetic capsaicin, natural capsaicin and dihydrocapsaicin in edible oil were (0.250±0.032), (0.123±0.015), (0.130±0.014) μg/kg,k=2.Conclusion: This uncertainty is mainly derived from the linear fitting of the standard curve and the uncertainty introduced by the analysis of liquid chromatography-mass spectrometry.

Abstract:Objective: In order to accurately and quickly discriminate cigarettes. Methods: After collecting the near-infrared spectra of different brands and reducing the interference factors through the spectral preprocessing method, the spectral pretreatment method, the population number of firefly algorithm (FA) and the number of iterations on the correct rate of cigarette classification were investigated by using firefly algorithm to optimize support vector machine (SVM) parameters. Results: The standard normal variable transformation (SNV) combined with the first derivative method (1D) was used for near-infrared spectroscopy preprocessing. Under the condition that the number of firefly populations was 20 and the number of iterations was 20, optimized support vector parameters could achieve better recognition. As a result, the classification accuracy rate of the training set was 100%, and the classification accuracy rate of the test set was between 96.67% and 100.00%. Conclusion: It shows that using near-infrared spectroscopy technology combined with FA algorithm to optimize SVM can achieve accurate identification of cigarette brands.

Abstract:Objective: To reduce the influence of data difference and spectral feature redundancy on beef quality recognition. Methods: A beef quality recognition method based on classification feature extraction and deep learning was proposed. The spectral feature extraction method of classified beef was designed, and the improved DPeak algorithm was used for adaptive clustering analysis of spectral data to realize the difference analysis of data. The objective function of beef spectral feature extraction was defined and solved by discrete lion swarm algorithm. The optimal spectral feature subset of each classification was extracted to minimize feature redundancy. The improved lion swarm algorithm (ILSO) was used to optimize the support vector machine (SVM) model parameters corresponding to each classification, and a beef quality recognition model integrating classification feature extraction and ILSO optimized SVM was proposed to complete the classification and evaluation of beef quality. Results: Compared with SSA-SVM and PCA-SVM, the recognition accuracy of this model is improved about 12.3%~14.5%. Conclusion: The beef quality recognition model based on classification feature extraction and deep learning can improve the accuracy of beef quality recognition.

Abstract:Objective: This study aimend to explore the appropriate transformation path of regulatory power for food safety "social co-governance". Methods: The state of "social co-governance" mode of food safety was analyzed and the possible secondary risks of "decentralization" of regulatory authority were analyzed, so as to explain the rational transformation of regulatory authority. Results: The blind decentralization of regulatory power will cause the policy risks of governance loss and disorder, leading to greater food safety accidents. Conclusion: It is necessary to make clear the transformation of "strict supervision to refinement and flexibility", adhere to the transformation of "basic rights of social co-governance" and "actively cultivate and stimulate the governance rationality of multiple subjects".

Abstract:Objective:To efficiently exploited the discarded eggshells and eggshell membranes. Methods: The discarded eggshells was separated and collected. Used Fluent and EDEM coupling simulation to study the flow field characteristic and particles trajectory, which affected by structure parameters such as upper outlet diameter and lower outlet diameter of the collecting barrel. By analyzing flow field characteristic and capture rate of eggshells as well as eggshell membranes, the size of collecting barrel was optimized. The top angle, the vacuum of suction machine, the feeding inlet air velocity, the solid load of feeding inlet were used as the test factors. The recovery rates of eggshells and eggshell membranes were used as the two evaluation indexes. The experiments of collecting eggshells and eggshell membranes were performed and optimized. Results: The simulation showed that an appropriate decrease of the diameter of the upper and lower outlets will lead to more loss pressure drop in the cylinder, and increase the tangential velocity in the cylinder. When the upper outlet diameter was 0.4D (D is the diameter of the cylinder) and the lower outlet diameter was 0.5D, the capture rate of eggshells and eggshell membranes was the highest. The test results showed when the cyclone top angle was 45°, the solid load rate was 1 000 g/s, the feeding inlet air velocity was 4.64 m/s, the vacuum of suction machine was 336.61 Pa, the eggshell membranes recovery rate was 92.94%, and the eggshells recovery rate was 97.90%. Conclusion: The vacuum of suction machine and the feeding inlet air velocity mainly affect the flow field in the collecting barrel, and the solid load will cause different interactions between materials. After the experiment and simulation analysis of the factors that affect the collecting effects, the optimal level combination of factors is obtained. With the combination of these factors, the recovery rates of eggshell and eggshell membrane are higher, and the collecting device has a good effect.

Abstract:Objective: In order to improve the picking efficiency of raw materials in large food processing and storage, a collaborative path planning method of food picking robot based on discrete multi-objective cuckoo algorithm is proposed. Methods: Aiming at the problem of picking multi location raw materials according to the proportion of food processing formula, the cooperative path planning model of multi-objective food picking robot was established, which took the total moving distance, total energy consumption and total weight of periodic picking raw materials as indicators and the Pareto optimal solution discrete multi-objective cuckoo algorithm (DMCA) was proposed. The three-layer cuckoo code was designed, and the renewal strategy of mutation, homogeneous evolution and heterogeneous evolution were redefined to improve the global optimization ability of DMCA. Also, an improved A* algorithm was designed to solve the best moving path between two cargo spaces, and DMCA was used to solve the collaborative path planning model, so that the planned path balanced the moving distance and energy consumption. Results: Compared with other algorithms, the total moving distance was reduced by about 6.3%, and the total energy consumption was reduced by about 7.5%. Conclusion: The proposed method can effectively improve the picking efficiency of raw materials in large-scale grid storage, which has a certain application and popularization value and the planned path balances the moving distance and energy consumption.

Abstract:Objective: Verify the feasibility of the task scheduling and algorithm test platform of the materials transportation robots system based on the actual order data. Methods: This paper discusses the design of simulation experiment through the independently developed platform, focusing on the typical scenarios of pharmaceutical logistics. Aiming at the logistics scenario of task allocation strategy of multi robot with task classification, the Memory Elite Population based Catastrophe Adaptive Large Neighborhood Search(MEPCALNS) algorithm is designed. Results: Compared with ALNS algorithm, the efficiency of MEPCALNS algorithm is increased by 3.16% on average. Conclusion: By means of algorithm optimization research and simulation operation comparison of various scenarios. The value of the platform in algorithm verification is proved, which shows the effectiveness of MEPCALNS algorithm in typical scenarios.

Abstract:Objective: To solve the problems of low dehydration rate of solidliquid separation device and discharge not free of kitchen waste. Methods: By Optimizing the parameters of the key parts of the solid-liquid separation device, modeling the solid-liquid separation device based on Creo, analyzing the extrusion process through EDEM simulation software, the optimized screw shaft prototype was made and verified. Results: The optimized spiral shaft structure parameters were conveying distance 373 mm, compression distance 180 mm, compression end diameter 96 mm, spiral blade diameter 98 mm and axis length 553 mm; the force range of solid-liquid separation device was 2.7~4.5 N, wtih average force of 3 N, and discharge speed range of 1.3 ~ 4.7 m/s with average speed of 1.9 m/s. Conclusion: The dehydration rate of kitchen waste solid-liquid separation device is significantly improved, the discharge is smooth, and the dehydration effect is better than that before optimization.

Abstract:Objective: Improve the speed and accuracy of foreign matter identification in food. Methods: Based on the LeNet-5 network structure, the improved CNN model was obtained by adding batch normalization layer and dropout layer. Using this model, a recognition system was established for the automatic recognition of foreign bodies in food images. The performance of the model was analyzed through experiments. Results: Compared with the traditional model, this model has higher detection accuracy and faster recognition speed. The recognition accuracy of food foreign bodies was 99.75% and the recognition time was only 0.332 s. Conclusion: The foreign object recognition model of dumpling image had good detection speed and recognition accuracy.

Abstract:In order to enhance the cultural value and design thinking of intangible cultural heritage food packaging design, and to spread the characteristics of traditional dwellings and traditional skills of intangible cultural heritage food, starting from cultural characteristics, architectural layout characteristics, architectural element characteristics and architectural color characteristics, Fujian Fuding white tea in east Fujian intangible cultural heritage food is the object of packaging design, which combines the characteristic elements of traditional residential buildings in eastern Fujian with the packaging design of local intangible cultural heritage food, and gives its packaging design significance and design strategy for feasibility design.

Abstract:This paper introduces the concept, origin and expression form of hand-painted illustration, analyzes the application value of hand-painted illustration in food packaging design, and studies the application of hand-painted illustration in food packaging design from four aspects: history and culture, humor and interest, emotional expression and brand concept, which provides a reference for different types of food packaging design.

Abstract:Objective:This study aimed to investigate the effects of different concentrations of ozone fumigation on the texture and nutritional quality of post-harvestAgaricus bisporus during cool storage. Methods:‘A15’A. bisporus was treated with ozone gas with concentrations of 14.89, 29.77 and 44.65 mg/m3 respectively, and the changes in related indicators of each group during (1±1) ℃ storage were analyzed, such as sensory, texture and nutrition. Results:When stored for 8 days, 29.44 mg/m3 ozone fumigation treatments effectively maintained good springiness, cohesiveness and resilience, and delayed the decrease of the sensory quality, hardness, soluble solids, vitamin C and soluble protein content. Conclusion: The 29.77 mg/m3 ozone fumigation treatment ofA. bisporus can most effectively to maintain it storage with an extension to 8 days.

Abstract:Objective:This study aimed to explore the effective method of high-oxygen modified atmosphere packaging for fresh cutting Aralia elata Seem. Methods:In order to explore the effects of high oxygen regulated packaging treatment on the sensory quality and physiological changes of fresh cutting A. elata, different combinations of high oxygen regulated packaging with carbon dioxide were carried out. Results:The results showed that 90% high-oxygen conditioning package treatment significantly reduced the changes of respiratory strength, hardness and color, inhibited the consumption of total sugar and total phenol, reduced the activities of enzyme browning related enzymes POD and PPO and MDA accumulation, and protected the dynamic balance of cell membrane system. Conclusion: 90% high oxygen combined with 10% carbon dioxide has the best effect, which can prolong the preservation period of fresh cutting and prickling buds.

Abstract:Objective: This study aimed to explore the changes of hygroscopicity and quality characteristics of different freeze-dried (FD) fruits and vegetables in the storage.Methods: Taking four kinds of fruits and vegetables, including potato, king oyster mushroom, apple and white radish, as the research objects, the changes of microstructure, hygroscopicity, color and texture characteristics of the four kinds of freeze-dried fruits and vegetables were observed, and the correlation analysis was conducted.Results: The results showed that the cell structure of fresh fruits and vegetables was plump and regular; The FD apple slices was observed with relatively complete tissue structure, thicker cell wall, slightly rupture, larger aperture, stronger hygroscopicity, and significantly reduced L* value was (P＜0.05).The pore structure of lyophilized potato slices was hexagonal, and there were a lot of starch particles in the cells. With small pores, the hygroscopicity was lower than that of lyophilized apple slices, and the color change was significant (P＜0.05). The lyophilized radish slices had compact structure and smooth surface, while the cells were wrinkled and deformed, and the pore size was not uniform, and the hygroscopic property was lower than that of lyophilized potato slices; the color of the material had no significant change after hygroscopic (P＞0.05). The structure boundary of lyophilized Pleurotus eryngii slices was filamentous, and the cell wall was broken seriously; the cell integrity was low, and the hygroscopicity was lower than that of lyophilized white radish slices. The color and luster of lyophilized white radish slices had no significant change (P＞0.05). The difference in quality indexes between the material before and after moisture absorption was obvious, while there was a significant or extremely significant correlation between the hygroscopicity and texture properties of materials (P＜0.05).Conclusion: There is a big difference in the texture of the material without moisture absorption and moisture absorption during the storage process, which affects the quality characteristics of the product.

Abstract:Objective:This study aimed to improve both the drying rate and quality of Undaria pinnatifida. Methods:Microwave vacuum drying experiment was carried out under different microwave power density, vacuum degree and pulse intermittent conditions. The thin layer drying model was established and the mass and heat transfer parameters were calculated. The drying process parameters were optimized by L9（34） orthogonal test with indicators of drying time, sensory quality, rehydration rate, energy consumption and material temperature. Results:Page model was found fit the drying kinetics well, and the change of drying kinetics showed obvious dependence on energy contribution of drying conditions. The effective moisture diffusion coefficient ranged from 2.38×10-9 to 1.49×10-8 m2/s and increased with the microwave power density. The enthalpy and entropy decreased, while the Gibbs free energy increased with the increase of drying temperature. The drying activation energy of U. pinnatifida was 4.51 kJ/mol. When the microwave power density was 4.5 W/g, with vacuum degree 80 kPa, the moisture content was reduced to 12.30% within 16 min, and the energy consumption was 0.04 kW·h/gH2O, with rehydration rate of 1 885.69% at an average drying temperature of 26.71 ℃. The leaves of U. pinnatifida were in dark green, flat and free of burning spots and bubbles.Conclusion:Microwave vacuum drying was a suitable method for drying U. pinnatifida with high efficiency, controllable quality. Most importantly, few difference between rehydrated specimen and fresh materials was found.

Abstract:Objective:To optimize the extraction process of flavonoids from Artemisia argyi and evaluate the antioxidant activity in vitro. Methods:The ultrasonic-microwave combined water extraction method of Artemisia flavonoids was determined, and the extraction process was studied with the yield of total flavonoid, DPPH radical scavenging rate and ·OH radical scavenging rate of Artemisia argyi. Based on the single factor experiment, the factors with greater influence were screened through Plackett-Burman design, then optimized extraction process by response surface test. Results:The best extraction process was ultrasonic power 340 W, ultrasonic time 27 min, microwave power 600 W, microwave time 120 s, solid-liquid ratio 1∶30 (g/mL). Under these conditions, the yield of total flavonoids can reach 87.93 mg/g, DPPH radical scavenging rate is 80.84%, ·OH radical scavenging rate is 77.92%. Conclusion:The yield of flavonoids by this method is significantly better than the traditional boiling and water bath extraction (P＜0.05), and the antioxidant activity of Artemisia argy is better.

Abstract:Objective: The Polygonatum cyrtonema was processed to investigated its effects on material and energy metabolism in CUMS depressed model mice.Methods: 80 KM/SPF mice were randomly divided into model group, positive group, processed P. cyrtonema group and compatible group, with male and female were equally divided. CUMS depressed mice model were established by unpredictable mild stress for 28 days. The levels of ICD, α-KGDHC, ATPs and Na+K+ ATPase in brain, cerebellum, liver, kidney and spleen were detected by ELISA.Results: Processed P. cyrtonema and its compatibility had different effects on the enzyme levels of material and energy metabolism in both male and female mice. Compared to the positive group, each treatment group was affected significantly (P＜0.05). P. cyrtonema could significantly increase the α-KGDHC content in brain, cerebellum, liver, kidney and spleen of female mice (P＜0.01), and complex differences in levels of ICD α-KGDHC, ATPs and Na+K+ ATPase in different organs of male and female mice were observed.Conclusion: Processed P. cyrtonema and its compatibility had different effects on the enzyme levels of marerial and energy metabolism in both male and female mice. P cyrtonema group had the strongest effect on depressed mice.

Abstract:Objective: This study aimed to investigate the antioxidant activity of polysaccharides fromPlatycodon grandiflorumand its hypoglycemic effect on type 2 diabetic rats.Methods: Extraction and determination ofP. grandiflorum polysaccharide content and its ability to scavenge different free radicals The rats were fed with high-fat and high-sugar feed for 6 weeks. After 6 weeks, the rats were intraperitoneally injected with STZ (30 mg/kg·BW) to establish type 2 diabetes models (T2DM), which were divided into normal group, model group, andP. grandiflorum-polysaccharide high-dose group (400 mg/kg) and low-dose group (200 mg/kg), and positive group (metformin 200 mg/kg). The body weight and fasting blood glucose (FBG) were measured regularly for 8 weeks. In the last week, an oral glucose tolerance (OGTT) test was performed, and rat serum and liver were taken to determine the changes in lipid metabolism indexes and related oxidases in rats.Results: The content of platycodon grandiflorum polysaccharide was 89.65%, and the scavenging ability of DPPH·, ABTS+·, ·OH and PTIO at a concentration of 1 000 μg/mL were 91.3%, 89.7%, 83.8%, and 90.4%, respectively. Compared with the model group,P. grandiflorum polysaccharide could effectively alleviate the weight loss of T2DM rats, significantly reduced their FBG (P＜0.05), and significantly increased the level of OGTT (P＜0.05). After high-dose treatment ofP. grandiflorum polysaccharide, the levels of TC, TG, LDL-C and MDA decreased significantly, and the levels of HDL-C, SOD, GSH, and CAT increased significantly (P＜0.05) with dose-dependence.Conclusion:P. grandiflorum polysaccharide has good antioxidant properties and can reduce blood sugar by improving lipid metabolism and oxidative stress levels in T2DM rats.

Abstract:Objective:To improve the extraction rate of blueberry anthocyanins and overcome the shortcomings of traditional extraction. Methods:Firstly, single factor experiment was used to explore the effects of four experimental factors on the yield of anthocyanins. Response surface methodology was used to design the combination experiment, and genetic algorithm was employed to optimize the extraction process. The dynamic model of MAE process was established based on Fick?s first law. According to Arrhenius equation and phase transition equilibrium principle, Ea, ΔS, ΔH, and ΔG in the extraction process were obtained to analyze the thermodynamics of microwave extraction process. Results: The optimum extraction parameters to achieve the highest yield of anthocyanins (83.15±2.03)% from blueberry via MAE were obtained at extraction temperature of 60 ℃, extraction time of 8 s, ethanol concentration of 57%, and solid-to-liquid ratio of 1∶32 (g/mL). The established kinetic model could predict the extraction effect of anthocyanins at different extraction temperatures. In the process of microwave extraction, the Ea, ΔS, and ΔH were 40 510 J/mol, 42.07 J/mol, and 190.64 J/mol, respectively. ΔG was less than zero, indicating that the microwave extraction process belonged to endothermic, entropy increasing and spontaneous process. Conclusion:The results provide theoretical basis and reference for the efficient extraction and deep development of anthocyanins.

Abstract:Objective:This study aimed to increase the diversity of surimi products and promote the industrialized production of high-quality traditional food. Methods:Using frozen surimi and chicken breast as raw materials, double-protein vermicelli was prepared by extrusion molding. The effects of raw material composition on the quality of double-protein vermicelli were studied by measuring its holding capacity, pulping value, color, stretch, texture and sensory evaluation. Results: The optimal mixing ratio of surimi and chicken was 8∶2, and the optimal amount of water was 20%. The tensile strength, tensile deformation and total sensory scores of the dual protein fish filaments prepared under this condition were increased by 23.84%, 28.13% and 17.39%, respectively, compared with the shredded fish without chicken. When 30% potato starch was added, the tensile strength and tensile deformation of dual-protein filaments reached the maximum values, which were 4.47 N/cm2 and 3.27 mm/mm, respectively, and the water holding capacity was better (73.27%) with lower pulp value (10.45%). When 3.5% salt was added, the water holding capacity, tensile strength, tensile deformation, elasticity and adhesiveness of dual-protein filaments all reached the maximum values, which were 68.62%, 4.94 N/cm2, 4.97 mm/mm, 6.48 N and 4.63 N, respectively. Conclusion:The mixing ratio of surimi and chicken was 8∶2, with the water content of 20%, the potato starch of 30%, and the salt of 3.5%, the quality of fish-chicken dual-protein vermicelli was optimum.

Abstract:Objective: This study aimed to improve the technological conditions of antioxidant activity of pumpkin polysaccharide. Methods:The effects of temperature, pumpkin powder/distilled water ratio of solid to liquid, inoculation amount and shaking speed on the extraction rate of bio-transformed pumpkin polysaccharide were investigated, and the scavenging ability of pumpkin polysaccharide on DPPH free radical was studied. Results:The optimal conditions were inoculation amount 1% and solid-liquid ratio 1∶30 (g/mL), with shaking speed of 100 r/min at 37 ℃. Under the control of these conditions, the scavenging rate of DPPH free radical was (54.61±1.58)%. The in vitro antioxidant activity of the bio-transformed pumpkin polysaccharide was significantly higher than that of the non-transformed one. Conclusion: Lactobacillus plantarum nbkBC299 could improve the antioxidant activity of pumpkin polysaccharide.

Abstract:Objective: This study aimed to obtain a novel fermented green tea with high ACE-inhibitory activity by Eurotium cristatum and to investigate its acute hypotensive effects on spontaneously hypertensive rats (SHR). Methods: The effects of pueraria addition, water content of substrate and spore suspension on ACE-inhibitory activity in vitro were investigated, and the fermentation process was optimized by orthogonal design experiment. The fermented tea solution was prepared by water extraction method, and SHR model was selected to study the hypotensive effect of fermented tea. Results: The optimal fermentation process for fermented tea was as follows: adding 2 g pueraria into 20 g green tea matrix, controlling the water content of the matrix to 20%, inoculatin 5% suspension of E. cristatum. Compared with the control group, different doses of fermented tea had lowering effects on blood pressure in SHR within 24 h. Conclusion: The acute hypotensive effect of the daily dose of 300~600 mg/kg was the most significant, which could lower the blood pressure of SHR in a short period of time.

Abstract:Objective: The effects of superfine chestnut powder on sponge cake quality was studied, aiming to provide a certain theoretical reference for improving the quality of bakery food. Methods: To explore the superfine chestnut powder adding amount on the sponge cake texture, sensory, baking, aging characteristics and nutritional quality, different contents of superfine chestnut powder were added during the making process of sponge cake. Results: The hardness, elasticity, chewiness and specific volume of cake had no significant change compared with the control group when chestnut powder was added less than 10%. The addition of chestnut powder could reduce the brightness and yellowness while increase the redness of the cake, and the effect on the color of the cake core was greater than that on the surface. Adding chestnut powder could reduce the cake bakingloss, aging enthalpy value and increase its nutritional quality. When the content of chestnut powder was 5%, the cake had the best color, shape, taste, hardness and overall preference. In general, the appropriate amount of superfine chestnut powder was 5%~10%. Conclusion: The addition of superfine chestnut powder endowed the sponge cake with better quality.

Abstract:The basic nutrition components and physiological changes after harvest of daylily were described, and the development status of daylily industry and storage and preservation technology were summarized in this review. Finally, the processing technology of daylily was prospected.

Abstract:This paper reviews the structure and stability of triplex nucleic acid, the progress of triplex nucleic acid-based fluorescence, electrochemical, colorimetric platform in detecting food borne hazards, and discusses the challenges and future development prospect of triplex nucleic acid-based detection technology in food safety field.