Abstract: Objective: This study aimed to develop novel soybean protein isolate （SPI）-based emulsifiers. Methods: The structure of SPI was modified by limited enzymolysis combined with glycosylation and the effects of this synergistic modification on the emulsification characteristics of SPI was studied. Results: Among the different components obtained from the SPI hydrolysate （SPIH）, the high molecular mass component （F30） exhibited the best emulsifying property. The emulsifying stability of F30-dextran conjugates obtained for 4 h was the best. Compared with SPI, SPIH and F30, the F30-dextran conjugates stabilized emulsions showed the lowest initial average particle size and the best storage stability. When the pH was close to the isoelectric point of SPI or the system was at a high salt concentration, all emulsions were unstable to cause aggregation. Compared with SPI, both SPIH and F30 stabilized emulsions had a higher aggregation degree. However, F30-dextran conjugates provided additional steric hindrance and hydrophilicity due to covalently bound dextran, which exhibited a higher resistance under adverse environmental conditions. Conclusion: Limited enzymolysis combined with glycosylation is a potential and reliable way to develop SPI-based emulsifying ingredients.
Abstract: Objective: Exploring the optimal process for the degradation of T-2 toxin in beer by glow discharge plasma（GDP） and its impact on the physicochemical indicators of beer. Methods: Based on single-factor experiments, a response surface optimization experiment with four factors and three levels was conducted using the Box Behnken method to determine the optimal degradation conditions for T-2 toxin in beer. Results: When the discharge voltage was 570 V, the action time was 18 minutes, the discharge current was 99 mA, and initial concentration of T-2 toxin was 8.5 μg/mL. Under the control of these conditions, the degradation efficiency of the T-2 toxin was the highest （89.21%）. After GDP treatment, the physical and chemical indicators of beer were tested, and the results showed a significant decrease in beer foam retention （P<0.05）, while other indicators remained unchanged. Conclusion: The optimal degradation conditions of GDP obtained by the response surface optimization model are accurate and reliable, which can be used for the degradation of T-2 toxin in beer. GDP can affect the brewing ability of beer, but it will not have a significant impact on other indicators.
Abstract: Objective： To improve the adsorption of genistein by zirconium-based metal-organic frameworks （MOFs） with triangle aromatic ligands. Methods： Two MOFs （MOF-808 and PCN-777） containing different sizes of triangle aromatic ligands were synthesized by hydrothermal method for adsorption of genistein. The synthesis of MOFs was determined by a series of characterization methods, and the adsorption performance was compared with that of a linear binary carboxylic acid ligand-constructed MOF （UiO-66）, to evaluate the effects of pore characteristics, hydrophobicity changes, and other factors on the adsorption performance, and to explore the adsorption mechanism by XPS analysis. Results： Compared with linear ligand-constructed UiO-66, the pore sizes of triangular aromatic ligand-constructed MOFs （MOF-808, and PCN-777） increased from 0.65 nm to 1.81 nm and 3.55 nm, respectively, and the water contact angles increased from 47.91° to 110.68° and 128.23°, respectively. The adsorption capacity and adsorption efficiency of genistein in linear ligand-constructed UiO-66 was 40.08 mg/g and 39.98%, respectively, while the adsorption capacity and adsorption efficiency of genistein in MOFs constructed by triangular aromatic ligand （MOF-808, PCN-777） was increased to 61.80 mg/g, 81.75 mg/g and 61.63%, 81.52% respectively. Conclusion： Metal-organic frameworks （MOFs） can be used for the adsorption and enrichment of genistein. Compared with linear ligands, the introduction of triangular aromatic ligands with different sizes changes the pore size and hydrophobicity of MOFs, enhances the internal accessibility of MOFs, and provides more adsorption sites, which improves the adsorption effect of genistein. The adsorption mechanism of genistein in PCN-777 is based on the synergistic combination of metal-chelating interactions, π-π interactions, and hydrophobic interactions.
Abstract: Objective: In this study, the effects of silymarin on the biofilm S. aureus ATCC25923 and its virulence factors were investigated. Methods: The inhibition and clearance of silymarin on S. aureus ATCC25923 biofilm formation were detected by crystal violet staining, the effects of silymarin on its biofilm metabolism were investigated by MTT staining, and the effects of silymarin on its coagulase expression and hemolytic activity were investigated by freeze-dried plasma and aseptic defibrinated sheep blood. In parallel, the effects of different concentrations of silymarin on its biofilm and Fourier transform were observed under an optical microscope. Results: The results showed that the minimum inhibitory concentration (MIC) of silymarin against S. aureus ATCC25923 was 0.5 mg/mL, the inhibition rate of silymarin to S. aureus ATCC25923 biofilm at MIC concentration reached 90%, and the clearance rate reached 89.2%, and the low dose of silymarin could significantly inhibit its hemolytic activity and coagulase expression. Conclusion: The outcomes of the experiment demonstrate the great potential applications of silymarin in the areas of natural preservatives and food safety.
Abstract: Objective: Obtaining hhigh-yield pprotease-pproducing bacterial resources through fermentation of advantageous protease-producing strains derived from Shiping stinky tofu. Methods: Single-factor and response surface experiments were used to optimize the culture medium and fermentation conditions. Using casein as the substrate, the effects of temperature, pH, metal ions and organic reagent on the protease activity and stability of strain JX-11 were investigated using enzymology techniques. Results: One strain of high-producing proteinase-secreting bacteria, JX-11, was isolated from Shiping stinky tofu, identified as Chryseobacterium pennipullorum. The optimal conditions for protease production by JX-11 strain were found to be temperature at 23.0 ℃, glucose content at 6.7 g/L, peptone content at 15.0 g/L, pH 6.4. Under these conditions, the protease activity was (39.16±3.24) U/mL. The optimal temperature for extracellular protease of JX-11 strain was 30 ℃, and it had good stability in the range of 10～40 ℃. The optimal pH was 7.0, and it had good stability in the range of pH 6.0～9.0. Mn2+ significantly increased the activity of JX-11 protease. The relative activity was increased by 4.33 times compared with the blank group. Zn2+, Cu2+, and K+ all inhibited the enzyme activity, Na+, Mg2+, and Ca2+ had no significant effect. Glycerol can promote the activity of the enzyme, but ethanol and acetone have little effect on it. Tween 80, acetic acid, methanol and EDTA inhibited the activity of the enzyme, among which EDTA hadd the most obvious inhibition, which further proved that the enzyme was a metalloprotease. Conclusion: A high-producing protease-secreting bacterial strain is obtained from Shiping stinky tofu, which has good application prospects.
Abstract: Objective: To study the molecular mechanism of celery seed inhibiting or treating gout by using network pharmacology and molecular docking. Methods: TCMSP database and the network maps were constructed with Cytoscape3.9.0 software. Gout-related targets were collected in GeneCard database and OMIM database, crossed with the main component targets of celery seed and imported into STRING database for protein-protein interaction （protein-protein interaction, PPI） analysis, core targets were obtained, core targets were introduced into DAVID, and GO function enrichment and KEGG pathway enrichment were performed in the database. Finally, AutoDock software was used to verify the key components with key targets. Results: There were 16 main components of celery seeds, 69 common targets. After topological analysis, quercetin, apigenin, luteolin, celery, five core components and 10 key targets of gout TNF, MAPK14, IL4, CXCL8, LYN, PDGFRβ, HCK, VEGFA, ITGA, IL2, were closely involved in inhibiting or treating gout. The results of GO and KEGG analysis showed that the core components of celery seed acted through regulating biological processes such as apoptosis, proliferation and migration, and through PI3K-Akt signaling pathway, IL-17 signaling pathway, MAPK signaling pathway, and NF-κB signaling pathway. The molecular docking results showed that the five core components were closely bound to the 10 key target proteins with high confidence, verifying the accuracy of the network pharmacology prediction results. Conclusion: This study reveals the role of celery seed in inhibiting or treating gout, and lays a foundation for the development of single Chinese herbal medicine and the study of "medicine and food homology" to control metabolic diseases.
Abstract: Objective: Improve the accuracy and robustness of papaya ripeness detection. Methods: A method of papaya ripeness detection based on multi-target sampling and improved Mask R-CNN was proposed. In the process of data expansion, the method introduced multi-object sampling technology to generate enhanced images from small data sets taken under controlled conditions, which was conducive to extending the proposed method to data sets with complex features of actual papaya images. The effectiveness and robustness of the proposed method were verified by means of average accuracy, accuracy, accuracy-recall curve and calculation time, and the results of papaya ripeness detection effect were compared with those of Faster R-CNN, RetinaNet and CenterMask. Results: The values of mean awerage precision, 50% mean awerage precision and 75% mean awerage precision for the papaya ripeness detection were 98.43%, 98.67% and 98.68%, respectively. The average accuracies for the ripeness detection of immature, semi-mature and mature papayas were 99.38%, 98.81% and 99.37%, respectively. Conclusion: This method can be used to develop an electronic system for papaya ripeness detection and improve the performance of papaya ripeness detection and grading.
Abstract: Objective: The objective of this study is to investigate the heavy metal content in sediment and various organs of Hunan lotus seed in a planting area, as well as to explore the characteristics of heavy metal accumulation and transfer in Hunan lotus seed. Methods: A typical planting area in Hunan Province was selected for this research. The contents of Cd, Cr, Pb, Ni, Cu, Zn and Mn were measured using an inductively coupled plasma emission spectrometer. The bioconcentration factor （BCF） and transfer factor （TF） were used to evaluate the heavy metal accumulation and transfer ability of Hunan lotus seed. Results: The average content of Cd, Cr, Pb, Ni, Cu, Zn, and Mn in the sediment were 0.73, 176.28, 40.48, 27.61, 28.07, 95.57 and 311.68 mg/kg, respectively. Compared with the limit values of NY/T 391—2021, the exceeding rates of Cd, Cr, and Pb content are 100%, 75%, and 10%, respectively. The highest concentrations and contents of these 7 heavy metals were Cd, Cu and Zn in the lotus core, Cr and Pb in the root, Ni in the lotus-seed kernel and Mn in the leaves, with an average content of 0.20, 13.64, 78.58, 14.66, 2.23, 1.11 and 924.03 mg/kg, respectively. The BCFMn values for both stems and leaves exceeded 1. The TFCu values for all organs were greater than 1. Conclusion: This study reveals that there is serious pollution from Cd within the study area. The content of heavy metals in different organs of Hunan lotus seed is different. Lotus stems and leaves has strong enrichment of Mn, and Cu had strong transfer ability in Hunan lotus seed.
Abstract: Objective: To achieve rapid, quantitative and high-throughput detection of aminoglycoside antibiotic residues in pork. Methods: Square-array aligned SERS substrates based on Au nanoflowers （AuNFs） were prepared using PP synthetic paper as a substrate. Pork samples were pre-treated by QuEChERs method and subjected to SRES. Results: Using 4-mercaptobenzoic acid as the SERS probe molecule, the substrate exhibited good homogeneity, SERS enhancement effect, reproducibility and stability. the SERS signal intensities at the characteristic peaks at 475, 619 cm-1 showed good linear relationships with the logarithms of the concentrations of gentamicin sulphate and neomycin sulphate, respectively （R2 of 0.991 6 and 0.990 7, respectively）. The limits of detections （LODs） were as low as 1×10-9, 1×10-8 mol/L, respectively, and were successfully applied to the rapid, quantitative and high-throughput determination of aminoglycoside antibiotics in pork. Conclusion: The experimental method provides an economical, efficient, time-saving and highly sensitive way for the application of SERS technology for the detection of antibiotic residues in real meat samples.
Abstract: Objective: This study aimed to evaluate the determination uncertainty of four quinolones residues in honey by liquid chromatography-tandem mass spectrometry （LC-MS/MS）. Methods: Based on GB 31657.2—2021, a mathematical model for sources of uncertainty evaluation was established. The uncertainty of each variable which affect the result were calculated and the weight of each uncertainty component was assessed. Results: The uncertainties in the determination of enrofloxacin, sarafloxacin, ofloxacin and ciprofloxacin in honey were （4.97±0.81）, （10.13±1.58）, （7.67±1.23）, （14.97±2.25） μg/kg （P=95%，k=2） respectively. Conclusion: The main influencing factors of the determination uncertainty were preparation and dilution process of standard solution and fitting of standard curve, which should be controlled in practical work.
Abstract: Objective: A method for the determination of 7 synthetic colorants in freshly prepared beverages by high performance liquid chromatography dual （HPLC） wavelength method with automatic solid phase extraction was established. Methods: Extraction conditions: The sample was extracted 2 times with pure water, and then the supernatant combined after centrifugation. The pH of the supernatant was adjusted to 3~4. After activation by an automatic solid-phase extraction device, loading, rinsing, and elution of the sample were carried out on the Poly-sery synthetic colorant solid-phase extraction column. The eluent was concentrated to 200 μL by nitrogen blowing, and then fixed to 1.0 mL with 50% mobile phase A+50% mobile phase B. Instrument conditions: The column was C18 column. The mobile phase was 20 mmol/L ammonium acetate-methanol, gradient elution. The flow rate was 1.0 mL/min. The injection volume was 10 μL. The detection wavelength were 254 nm and 628 nm. Results: The correlation coefficient of each substance in the range of 0.5～50 μg/mL was greater than 0.999 9, the detection limit of the method was 0.023～0.179 mg/kg, the quantitative limit was 0.078～0.598 mg/kg, the standard recovery was 92.4%～96.8%, and the relative standard deviation （RSD） was 1.2%～4.2%. Conclusion: This method has low consumption of toxic reagents, simple operation steps, high degree of automation, good recovery and repeatability, and it is suitable for the determination of large quantities of samples.
Abstract: Objective: Taking Guangxi Liupao tea as an example, an UPLC-MS/MS analysis method with residual amounts of matrine and Oxymatrine was established. Methods: The prepared samples were subjected to optimized acetonitrile aqueous solution （80% acetonitrile+0.2% ammonia water） ultrasonic extraction, mobile phase: formic acid water and formic acid methanol （both 0.1%）, gradient elution, and internal standard method quantification. Results: It was linear in the range of 0.1～80.0 ng/mL, r was greater than 0.999 6, the detection limits of matrine and oxymatrine were 1.0 μg/kg, and the quantitative limits were 3.0 μg/kg, which met the regulatory determination requirements for the residue of matrine and oxidative matrine in tea. Through the spike verification, the recovery rate was in the range of 92.0%～104.7%, and the relative standard deviation （RSD） was less than 5.4%. Conclusion: Method combined with purification tube purification （147.7 mg PSA, 15.1 mg GCB, 887.2 mg magnesium sulfate）, using Kinetex 2.6 μm Biphenyl 100 chromatographic column （100 mm×3.0 mm） separation solves the problems of low extraction recovery rate and complex pre-treatment of matrine and oxymatrine, so that the symmetrical peak shape and strong anti-interference ability of matrine and oxymatrine.
Abstract: Objective: To analyze and evaluate the uncertainty of the determination of folic acid content in milk powder by microplate method. Methods: The content of folic acid in infant formula milk powder was determined by microplate method according to GB 5009.211—2022 "National Standard for Food Safety-Determination of Folic Acid in Foods". Various experimental factors affecting the test results were analyzed and calculated according to the uncertainty evaluation methods and guidelines such as JJF 1059.1—2012, CNAS-CL01-G003:2011 and CNAS-GL05:2011, and the synthetic standard uncertainty and expanded uncertainty were obtained. Results: The expanded uncertainty U95=22.08 μg/100 g（k=2）, and the folate content of the sample was （282.33±22.08） μg/100 g. The uncertainty mainly comes from the process of microplate inoculation, the fitting of standard curve and the repeatability of measurement. Conclusion: The accuracy of pipettes and microbial factors have a great impact on the experimental results, so it is necessary to ensure the quality of the instrument and strictly follow the standardized procedures to minimize the uncertainty.
Abstract: Objective： A surface evaporation concentration device were designed to concentrate thermosensitive feed liquid at low temperature under normal pressure with low energy consumption. Methods： Based on an introduction to the working principle of the device, the basic equations of the device were given. The changes of volumetric evaporation flux and energy saving ratio with flow rate of the feed liquid, feed liquid temperature, sweeping gas flow rate, sweeping gas temperature were calculated and analyzed. Designed an experimental platform and obtained a set of optimal performance parameters through experiments. Results： The results showed that when the flow rate of the feed liquid was 0.02 kg/s, the device had the highest energy saving ratio and higher volumetric evaporation flux; When the temperature of the feed liquid increased from 30 ℃ to 50 ℃, the volumetric evaporation flux increased by 224.68%, but the energy saving ratio decreased by 12.42%; When the sweeping gas flow rate increased from 0.004 kg/s to 0.006 kg/s, the volumetric evaporation flux increased by 23.45%, but the energy saving ratio decreased by 7.74%; When the temperature of the sweeping gas increased from 10 ℃ to 30 ℃, the volumetric evaporation flux decreased by 22.92%, but the energy saving ratio increased by 37.49%; An experimental device was established to test orange juice with a sugar content of 15 °Brix, the results showed that when the feed liquid temperature was 38 ℃ and the sweeping gas temperature was 26 ℃, the volumetric evaporation flux of the device could reach 219 kg/（m3·h）, and the energy saving ratio could reach 3.3.Conclusion： The heat pump assisted random filler surface evaporation device has the characteristics of low temperature concentration under atmospheric pressure and low energy consumption when concentrating thermosensitive feed liquid．
Abstract: Objective: To optimize the operating parameters of wheat milling in roller mill I skin mill to reduce the energy consumption of milling. Methods: Using EDEM discrete element simulation software, Box-Behnken test was designed for key milling factors such as roll pitch, feeding amount, rotational speed and rotational speed ratio to investigate the relationship between operating parameters and milling power. Results: The significance rankings of the effects on the toothed roll crushing power were, in order, speed ratio, roll pitch, feed volume, speed ratio quadratic term, roll pitch quadratic term, interaction of roll pitch and speed ratio, interaction of feed volume and speed ratio, and interaction of roll pitch and feed volume. According to the different requirements of the I-skin mill, the optimal parameter combinations were obtained: the finer powder output with a rolling pitch of 0.67 mm, a feeding amount of 803.60 kg/（cm·d）, a fast roller speed of 537.68 r/min, and a rotational speed ratio of 2.64, and the coarser powder output with the optimal low-power consumption of 0.79 mm, a feeding amount of 803.83 kg/（cm·d）, a fast roller speed of 576.08 r/min, and a rotational speed ratio of 2.23. Conclusion: The error between the simulation results and the measured results is within a reasonable range, and the established discrete element milling model can be used for power prediction in wheat milling.
Abstract: Objective: To solve the problems of low level of automation and high labor intensity of workers in the fermented grains discharging process of solid-state fermentation in the ground-pot. Methods: An automatic fermented grains scooping strategy for the compound robot for fermented grains scooping was proposed. Based on the pre-processing of the ground-pot image and the reconstruction of the point cloud inside the inner edge, the point cloud segmentation algorithm was used to extract the point cloud of fermented grains. The scooping plane was constructed. The safe working distance for scooping was solved. Preset scooping points were set. Afterwards, the scooping amount of the preset scooping point was evaluated by the pixel surface element voxel algorithm, to select the optimal scooping point. Results: The method of planning the scooping point based on the safe working distance is reasonable, which ensures that the bucket does not collide with the ground-pot wall while scooping fermented grains from the wall at different depths of the scooping plane. The strategy can effectively reduce the number of robot scooping, thereby improving the efficiency of fermented grains scooping. Conclusion: The strategy can effectively guide the compound robot to realize the automatic and intelligent fermented grains discharging.
Abstract: Objective： This study aimed to solve the problems of yellowing, discoloration and quality preservation of broccoli after harvesting. Methods： Broccoli was fumigated with chlorine dioxide gas at different mass concentrations (0,0.2, 0.5, 1.0, 1.5, 2.0 mg/L) at 23 ℃, and the sensory, color, yelination grade, physiological and biochemical indexes and related browning enzyme activities of broccoli were determined after 0,2,4,6,8 days of storage. Results： Compared with the control group, different mass concentrations of ClO2 could inhibit the mass loss rate, yellowing browning and spoilage of flower buds of broccoli. ClO2 at 0.5 and 1.0 mg/L had a more significant effect on the maintenance of chlorophyll content, color difference a* and b*, and the inhibition of PPO and POD enzyme activities in broccoli. Among them, 0.5 mg/L ClO2 had the best effect on maintaining the color difference value of broccoli flower buds, and the yelination grade was still grade Ⅱ on the 8th day of storage. Simultaneously, it effectively maintained the vitamin C content and delayed the yelination and Browning of flower buds. Conclusion： It is necessary to control the concentration of ClO2 gas in the fumigation treatment of broccoli to obtain the best effect of maintaining the fresh green of broccoli bulbs and extending the shelf life.
Abstract: Objective: A new type of natural food preservative with pork liver as the main raw material was developed. Methods: Water-soluble porcine liver protein (WSLP), salt-soluble porcine liver protein (SSLP) and chitosan (CS) were combined to create edible composite membranes. The edible membrane components were then examined from a variety of perspectives using mechanical properties, Fourier transform infrared spectroscopy (FT-IR) and microstructure analysis. Utilized to preserve pork, and by contrasting the changes in the physical and chemical indices during the chilling process, the freshness retention capabilities of the composite film were investigated. Results: With the addition of WSLP and SSLP, the mechanical properties of edible film showed a trend of increasing firstly and then decreasing. The film was best when the amount was 40%, its film thickness was (0.267±0.001 43) and (0.264±0.001 21) mm, the tensile strength was (9.63±0.29) and (4.43±0.37) MPa, and the elongation at break was (58.37±0.90)% and (28.24±0.63)%, respectively, which were significantly different from CS film (P<0.05), and the FT-IR results showed that it was 40% WSLP and SSLP maximize cross-linking between membrane matrices. The results of scanning electron microscopy showed that the surface of the composite film prepared by 40% WSLP and SSLP was smooth and flat, and the microstructure was the best. After refrigerating pork for 12 days; It was found that 40% SSLP composite film had the best preservation performance, and the pH, total number of colonies, TVB-N value and TBARS value were the smallest in the four groups under different treatments. Conclusion: The composite membranes prepared by 40% WSLP and SSLP have the best performance.
Abstract: Objective: The preservation effects of four packaging materials on passion fruit were studied. Methods: The fruit of passion flower cv. Huangjin （maturity: eight） was used as the research material, and passion flower fruit was treated via polyvinyl chloride （PVC） film, polyethylene （PE） bag, bidirectional stretch polyolefin （BSP） heat shrinkable film, biodegradable modified atmosphere （BMA） bag, respectively, with untreated ones as the control group. Then, the fruits was stored at temperature of （25±1） ℃ and relative humidity of 85% for fifteen days, and the preservation indices of fruit were measured every three days. Results: Compared to control passion fruit, the four treatments of packaging materials could delay the peak of respiration and ethylene, slow down the increase of pericarp malondialdehyde content to stabilize cell membrane structure, delay the fruit etiolation and shrinkage, keep a lower weight loss rate and a higher commercially acceptable fruit rate, and maintain the pericarp appearance color and pulp nutrients contents. Among the different packaging materials, BSP heat shrinkable film had the best effects. Conclusion: The BSP heat shrinkable film might be used as a suitable storage technology to improve the quality and prolong the storage life of harvested "Huangjin" passion fruit.
Abstract: Objective: This study aimed to demonstrate the potential immunomodulatory activity in mice of rice immunopeptide GBP1 （NSVFRALPVDVVANAYR） screened previously. Methods: Animal experiments were conducted to investigate the immunomodulatory mechanism of GBP1 peptide. RNA-Seq was used to sequence the transcriptome of mouse spleen tissues before and after GBP1 peptide treatment, and the molecular mechanism of GBP1 peptide immunomodulatory effect was explained. Results: In the GBP1 peptide treatment group, the number of spleen cells tended to be normal, the liver organ coefficient decreased significantly, and the serum IgG content was stable.GBP1 peptide can affect the expression of cytokines, mediate signal transduction pathways, and exercise immune regulation function, and inhibit the secretion of IL-2, IFN-γ and TNF-α in serum of mice. Through transcriptome analysis, 780 differentially expressed genes were obtained from spleen tissue, which were closely related to immune-related p53 signaling pathway, ferroptosis, complement and coagulation cascade in the body. Conclusion: GBP1 peptide can affect the expression of cytokines, mediate signal transduction pathways, and exercise immune regulation function.
Abstract: Objective: To explore the effects of Brassica rapa L. acid polysaccharide 1 (BRAP-1) on H226 cell tumor-bearing mice. Methods: 60 mice were divided into the model group (0.1 mL/10 g), positive cisplatin [3 mg/(kg·2 d)], BRAP-1 low dose [50 mg/(kg·d)], BRAP-1 medium dose [100 mg/(kg·d)] and BRAP-1 high dose [200 mg/(kg·d)]. During the experiment, the tumor growth of mice was observed, and the tumor inhibition rate and organ index were calculated; The levels of interleukin-18 (IL-18), interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in serum were detected by enzyme-linked immunosorbent assay. The gene expressions of IL-18, IL-1β, RIP-1(receptor-interacting protein-1), RIP3 and MLKL (mixed-lineage kinase domain-like protein 3) were detected by Real-time Quantitative PCR (q-PCR) and Western blot (WB). Results: Compared with the model group, the low and middle dose of BRAP-1 groups had significant tumor inhibition effects (P＜0.05), and the positive group and the high dose of BRAP-1 group had significant tumor inhibition effects (P＜0.01). Compared with other groups in the model group, the serum levels of IL-1β in the positive group and the high dose of BRAP-1 group were significantly increased (P＜0.01), IL-18 and TNF-α were significantly decreased in the positive group (P < 0.05), and were significantly increased in each dose of BRAP-1 group (P < 0.01). The results of q-PCR and Western blot showed that compared with the model group, the relative expression of IL-1β mRNA decreased with the increase of BRAP-1 dose (P＜0.01), while the relative expression of IL-18, MLKL, RIP1, and RIP3 mRNA and protein increased (P＜0.01). Conclusion: BRAP-1 can inhibit the growth of lung squamous carcinoma H226 cells by regulating the necrotizing apoptosis-related proteins MLKL, RIP1, and RIP3 and regulating immune cytokine levels.
Abstract: Objective: This study aimed to develop antioxidant products and anti-diabetes drugs of wampee. The study aimed to research the structural characteristics, anti-oxidation and hypoglycemic properties in vitro of polysaccharides from different parts of wampee. Methods: The structural properties, in vitro antioxidant and hypoglycemic activities of polysaccharides from the fruit, peel and seeds of wampee (CWP-F, CWP-P, and CWP-S) were analyzed and compared from the aspects of chemical composition, molecular weight, monosaccharide composition, appearance, DPPH free radical scavenging rate and α-amylase inhibition rate. Results: CWP-F had the highest molecular weight and was mainly composed of galactose and arabinose, CWP-P was mainly composed of galacturonic acid and arabinose, and CWP-S was mainly composed of glucose. The absorption peaks of the carboxylic acid structure were found in the Fourier transform infrared spectra of the three polysaccharides. Scanning electron microscopy results showed that the surface structure of the three polysaccharides was fluffy. CWP-P had the strongest antioxidant capacity, and its DPPH free radical scavenging rate, OH free radical scavenging rate, and total reducing power all were higher than those of CWP-F and CWP-S. CWP-P had the strongest hypoglycemic ability, followed by CWP-F, and CWP-S had no hypoglycemic ability. Conclusion: In vitro, CWP-F, CWP-P, and CWP-S exhibited varying compositions, structures, and antioxidant and hypoglycemic activity. Notably, CWP-P has shown the most robust antioxidant and hypoglycemic properties.
Abstract: Objective: This study aimed to determine the extraction solvent and compare the distribution of functional ingredient and antioxidant activities in different parts of Penthorum chinense pursh. Methods: the total phenolic content, total flavonoid content, antioxidant capacity and individual phenolic compounds content in Penthorum chinense pursh were determined and analyzed. Results: The total phenolic content, total flavonoid content increased and then decreased with the increase of solvent concentration. The seven main phenolic compounds （catechin, rutin, pinocembrin-7-O-glucoside, quercetin, kaempferol, pinocembrin and thonningianin A）, ABTS radical scavenging ability, and ferric ion reduction ability were the highest in 80% ethanol extract. The contents of totalphenolic content, total flavonoid content, ABTS radical scavenging ability, DPPH radical scavenging ability and ferric ion reducing ability of different parts of Penthorum chinense pursh were flower > leaves > stem. The total phenolic content, total flavonoid content, antioxidant capacity of flower and stem decreased significantly with the increasing of storage time, while leaves were relatively stable. In addition, the antioxidant activities of Penthorum chinense pursh were significantly positively correlated with total phenolic content, catechin, isoquercetin, kaempferol-3-O-rutinoside, afzelin, and pinocembrin-7-O-glucoside （P < 0.01）. Conclusion: 80% ethanol appears the most effective for polyphenol extraction in Penthorum chinense pursh, and the leaves have the great potential for development and utilization with high content and stable antioxidant activity.
Abstract: Objective: Clarify the flavor characteristics of Tremella fuciformis cultivated on herbaceous substrate. Methods: In the study T. fuciformis cultivated on herbaceous substrate was used as the research object, while samples of yellow tremella and white tremella cultivated on conventional substrate were used as controls. The differences in flavor composition between them were analyzed using high-performance liquid chromatography and Headspace Solid Phase Microextraction Ggas Chromatography Mass Spectrometry (HS-SPME-GC-MS). And combined with intelligent sensory technology, its flavor characteristics were analyzed. Results: According to multi-dimensional evaluations such as fresh and sweet amino acid and flavor nucleotides content, taste activity value and equal freshness concentration value, and electronic tongue, the freshness intensity of this herb's tremella was lower than that of yellow tremella and white tremella. The results of HS-SPME-GC-MS analysis showed that 82 volatile compounds were identified in this herb Tremella, which were higher than those in white Tremella (71 species) and yellow Tremella (49 species). The main compounds were esters, accounting for 16.9%～22.4%, presenting a strong floral aroma. At the same time, 26 characteristic aroma components of Tremella, 9 unique components of white Tremella, and 4 unique components of this herb Tremella were identified; In terms of aroma substance content, this herb Tremella also holds an advantage. Conclusion: The traditional Chinese medicinal fungus has a light taste and a strong aroma, making it suitable for developing and preparing beverages, while yellow white fungus is more suitable as a dish.
Abstract: Objective: The difference in bioactive substance content and bioactivity in black beans were compared. Methods: The contents of total phenolic acids, total flavonoids, condensed tannins, total anthocyanins, total polysaccharides and total proteins of nine kinds of black beans were determined. The antioxidant activities of black bean extracts in vitro and their inhibitory effects on α-amylase, pancreatic lipase, acetylcholinesterase and tyrosinase were compared. Results: The contents of total phenolic acid, total flavonoids, condensed tannins and total anthocyanins were as follows: equine bean > small black bean > black bean; Total polysaccharide content: small black bean > black bean > horse bean; Total protein content: horse bean > black bean > small black bean. Antioxidant activity: horse bean > small black bean > black bean. In vitro experiments showed that little black bean and black bean had inhibitory effects on many enzymes, and the intensity was different. Conclusion: The contents and functions of bioactive substances in different varieties of black beans are different. Black beans are more suitable for eating, and horse bean and small black beans have higher medicinal value.
Abstract: Objective： Based on transcriptome sequencing analysis, the effect of grape seed procyanidins on HepG2 cell genes and related functions was identified. The key genes and metabolic pathways involved in the treatment of HepG2 cells with procyanidins were confirmed. Methods: Through transcriptome sequencing, screening differential genes, gene functional annotation and enrichment analysis of the KEGG pathway, transcriptome studies were conducted on grape proanthocyanidin-treated cells. Results: After treating HepG2 cells with grape anthocyanins, the main biological processes enriched are cellular processes, metabolic processes, biological regulatory processes, immune system processes, reproductive regulation, and growth regulation. Research has found that 12 key differentially expressed genes in cell apoptosis are associated with TNF, p53, MAPK, PI3K-Akt and NF-κB signaling pathway is closely related. Conclusion: Cell apoptosis is closely related to the TNF signaling pathway, p53 signaling pathway, PI3K/Akt signaling pathway, NF-κB signaling pathway and MAPK signaling pathway.
Abstract: Objective: This study aimed to explore the copigmentation formula of purple corn anthocyanins. Methods: In this study, fructose, tannic acid, and pectin were used as co-pigmentation. The response surface method was used to optimize the co-pigmentation formula of purple corn anthocyanins, and the untreated purple corn was used as a control test. The anthocyanin components, color, texture, taste and antioxidant activity (DPPH free radical scavenging ability, ABTS free radical scavenging ability, and FRAP iron ion reducing ability) of purple corn after different treatments were determined. Results: 19% fructose, 0.07% tannic acid, and 1.9% pectin had the best copigmentation effect. Compared with the control group, the contents of cyanidin-3-O-glucoside, geranium-3-O-glucoside, and peony-3-O-glucoside in purple corn increased by 77.64%, 64.82%, and 54.75%, respectively. The total anthocyanin content increased by 67.98%. The L* value, b*value, and ΔE value of color decreased, while the a* value increased. Hardness, adhesiveness, and chewing type increased, while elasticity and cohesion decreased. The bitter, astringent, and astringent aftertastes differ slightly, as do the sour, sweet, salty, umami, bitter, and umami aftertastes. In the mass concentration range of 0.02~0.10 mg/mL, the DPPH free radical scavenging ability, ABTS free radical scavenging ability and FRAP iron ion reducing ability of purple corn anthocyanins were 39%~79%, 54%~74% and 27%~67%, respectively. Conclusion: The co-pigmentation effect of 19% fructose, 0.07% tannic acid, and 1.9% pectin on purple corn anthocyanins was the best.
Abstract: Objective: To Prepared of β-Cyclodextrin inclusion complex with Foeniculum vulgare（fennel） volatile ooil and study on its sstructural characterization and stability. Methods: Based on the inclusion rate, the inclusion yield and the content of trans-anethole in the inclusion compound, the comprehensive evaluation index was established, and the effects of the ratio of fennel volatile oil to β-cyclodextrin, inclusion temperature and inclusion time on it were explored. The preparation process was optimized by orthogonal test. It was characterized by scanning electron microscopy, thin layer chromatography, Fourier infrared spectroscopy and differential scanning calorimetry. Finally, the stability of the inclusion compound was investigated by light, high temperature and high humidity tests. Results: The optimum conditions obtained by saturated aqueous solution method were as follows: the ratio of volatile oil to β-cyclodextrin was 1∶8 (mL/g), the inclusion temperature was 40 ℃, the inclusion time was 60 min. Under these conditions, the inclusion rate of fennel volatile oil inclusion compound was 96.90%, the inclusion yield was 93. 61%, the content of trans-anethole was 6.81%, and the comprehensive score was 99.68. The inclusion compound was white powder with loose texture and good inclusion effect. The inclusion compound was characterized by scanning electron microscopy, thin layer chromatography, Fourier infrared spectroscopy and differential scanning calorimetry. Its stability was good within 5 days of illumination (4 000 lx), volatile components in the inclusion compound were easy to lose at high temperature (60 ℃) for a long time, and it would deliquesce and agglomerate when the relative humidity was more than 75%. Under the conditions of long illumination time, high temperature and high humidity, the inclusion rate and trans-anethole content were obviously reduced. Conclusion: The inclusion rate and inclusion yield of the above-mentioned optimal inclusion process are high, and the process is stable. When stored in a dry and sealed environment at room temperature, the β-cyclodextrin inclusion compound of fennel volatile oil has certain stability compared with the volatile oil.
Abstract: Objective: This study aimed to explore suitable drying methods for oil tea powder, making it easier for oil tea consumption and storage. Methods: Spray drying, vacuum freeze drying and vacuum drying were used to dry oil tea soup, and the quality (moisture content, sensory evaluation and color) and volatile substances of dried oil tea powder were evaluated. Results: The sensory score of vacuum freeze-drying oil tea powder was the highest (93), the water content was the lowest (3.78%), and the color was better（ΔE value 49.74). 104 volatile substances were identified from three drying methods of oil tea powder using SPME-GC-MS technology, of which 14 affected the flavor of oil tea powder. The characteristic flavor substances (nonanal, decanal, (Z)-2-decanal, (Z)-2-nonenal, (E) -3,7-dimethyl-2,6-octadienal) of freeze-drying present green fragrance and fat fragrance. The special aromas of spray drying and vacuum drying are (Z)-3,7-dimethyl-2,6-octadienal, (E)-3,7-dimethyl-2,6-octadienal and decanal, presenting green fragrance, fruit fragrance, and wax fragrance. PCA and comprehensive evaluation indicate that vacuum freeze-drying has the best flavor quality, which is consistent with sensory evaluation results. Conclusion: The flavor quality of vacuum freeze-drying was the best.
Abstract: In this review, several mechanisms of antihypertensive peptides derived from food and its by-products were summarized. Mechanisms based on the RAAS system such as ACE/Ang Ⅱ/AT1R signaling pathways and ACE2/Ang (1-7)/MasR signaling pathways were included. Mechanisms targeting at KNOS system including PI3K/Akt/eNOS signaling pathway, PPAR-γ/caspase3/MAPK/eNOS signaling pathway and L-type Ca2+ channel were also discussed. In addition, the pathways of reducing blood pressure by inhibiting endothelin-converting enzyme (ECE) activity discovered in recent years were also introduced.
Abstract: Steamed bread, noodles, deep-fried dough sticks and other noodle foods are an important part of our diet, and gluten protein is an important component of noodle foods. Common food processing techniques used to prepare noodles, including heating, freezing, mechanical processing, fermentation, and electric field treatment, alter the hydrophobic disulfide bond of the protein, denature and aggregate the protein, and cause other intricate physical and chemical changes, all of which have an impact on the texture and flavor of the finished noodle product. This paper mainly introduces the current research status of the influence of processing methods such as heating, freezing, crushing, kneading, extrusion, fermentation, and electric field processing on the structure and properties of the gluten protein.
Abstract: Pectin is a kind of natural polysaccharide polymer, which is an important part of the cell wall of higher plants. It has physiological functions such as cholesterol-lowering, anti-tumor, anti-oxidation and hypoglycemic, and beneficial to intestinal health. In this review, pectin extraction methods and their advantages and disadvantages in recent years were summarized, and the yield, galacturonic acid content and esterification degree of pectin extracted from different sources and methods were compared and analyzed. The physiological function of pectin and its application in various aspects were also introduced, and the future development direction was prospected.
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: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: 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: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: 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: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: 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: 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 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: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 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: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: 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: 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: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: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 aims to explore the correlation between the types and contents of fatty acids and lecithin in fresh walnut.Methods:A kinds of 20 walnuts were selected from Chengdu in Sichuan Province. The method of the gas chromatography and the high performance liquid chromatography were used for quantitative determination. Correlation analysis and cluster analysis were used to analyze the results.Results:The fatty acid composition of 20 kinds of fresh walnut was the same basically, with significant differences in content (P＜0.05). Longnan 15 had the highest oleic acid content. The contents of linoleic acid, arachidonic acid and cis-11-eicosenoic acid of Guangfeng 1 were the highest. The variation coefficient of lecithin was relatively small, and the content of lecithin was the highest in Xilo 3. The content of lecithin in fresh walnut had a high correlation with the content of fatty acids, and unsaturated fatty acids are highly associated. When the euclide distance was 15, the 20 walnut species could be divided into 3 categories.Conclusion:Longnan 15 and Guangfeng 1 are walnut varieties with high oil quality relatively; Xilo 3 is a walnut variety resource with high content of lecithin relatively.
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: 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: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: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：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: 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: 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: 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: 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: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: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: 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: 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: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: 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: 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 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: 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: 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)
