Abstract:Food material is the key factor of food 3D printing. This review summarized the characteristics of food materials (protein, starch, hydrogel and fat) commonly used in food 3D printing at present, analyzed the influence of different material combinations on the forming performance. Moreover, suggestions on how to improve the printing effect of difficult printing materials were also provided, and the technical bottleneck of food materials development faced in food 3D printing nowadays were noticed. Finally, the direction of food 3D printing technology in the future was prospected.

Abstract:Objective: Provide data support for the source tracing and pollution prevention of Pseudomonas aeruginosa in drinking water in Hunan Province. Methods: According to the national food safety standards of GB 8538—2016, the bottled water was tested randomly collected from partial cities and counties in Hunan Province, and the whole genome sequencing and molecular traceability of the 18 strains of Pseudomonas aeruginosa were detected. The carrying of virulence genes and drug resistance genes was detected. Results: It was confirmed that four strains of Pseudomonas aeruginosa showed consistency in terms of geographical distance, genetic distance, pathogenic and drug-resistant genotypes, and it was presumed that there was the same source. Conclusion: The traceability analysis of Pseudomonas aeruginosa in drinking water and the analysis of virulence and drug resistance genes in drinking water can be realized by whole gene sequencing based on 16S rRNA and single-copy orthologous genes.

Abstract:Objective: This study aimed to purify crude polyphenols from wormwood and to study inhibitory activity of its against α-glucosidase. Methods: The adsorption-desorption properties of wormwood polyphenols by seven kinds of macroporous resins were studied. The suitable resin for separating and purifying Wormwood polyphenols was obtained and the purification parameters were optimized. Using different concentration ethanol solution for dynamic elution, the inhibitory activity of different elution fractions on α-glucosidase was investigated. Results: The results indicated that D101 resin was a suitable material for purifying wormwood polyphenols and the macroporous resin reached equilibrium within 120 min. The optimal conditions for purifying wormwood polyphenols were as follows, crude polyphenol 1.5 mg/mL, pH 2.0, flow velocity of 1.5 mL/min, and 60% ethanol was used as the eluent with the elution flow rate of 1.5 mL/min. The purity of polyphenols increased from 21.42% to 69.19% after purification by D101 resin, which was enhanced 3.23 times. Different elution components were obtained by using different concentration ethanol as eluents, respectively. The 60% ethanol elution fraction that contained isoquercitrin, phloridzin and rutin had the best inhibitory effect on α-glucosidase activity. Conclusion: wormwood polyphenols have good development prospects for hypoglycemic effect.

Abstract:Objective: Investigate young people's taste preference for white bud kiran tea and design tea drinks accordingly. Methods: Design a combination of electroencephalogram （EEG）, electrodermal activity （EDA）, heart rate variability （HRV） multivariate statistical analysis and sensory evaluation to allow 24 subjects （12 of each gender） to evaluate the taste preference of seven batches of white bud kiran tea of different grams and brewing lengths. Results: the mean values of power spectral density, HRV and EDA of EEG can predict the taste preference of the subjects more accurately, and the mean values are negatively correlated with the liking level. A two-way analysis of variance shows that HRV and EDA are not affected by gender differences between subjects and the subject tea sample. Conclusion: Most of the subjects preferred the taste of 10 grams of white bud kiran tea brewed for 10 seconds.

Abstract:Objective: To established a method for determination of 21 perfluorinated compounds in animal-derived food by ultra-performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS）. Methods: The sample was extracted with 1% formic acid-acetonitrile, cleaned up with a sorbent mixture of N-propylethylenediamine （PSA）, octadecyl bonded silica gel （C₁₈） and graphitized carbon black （GCB）, then separated by acetonitrile-5mmol/L ammonium acetate aqueous solution and Acquity UPLC^ BEH C₁₈, detected by liquid chromatography tandem mass spectrometry in negative mode using the multiple reaction monitoring （MRM） mode. Results: The calibration curves were linear in the range of 0.2~10 ng/mL for the 21 PFAS. The limits of quantification were 0.25 μg/kg. Average recoveries were in the range of 71%~118% with three spiked levels, namely 0.25, 0.50, 1.25 μg/kg. The relative standard deviations （RSDs%） of inter-batch and intra-batch were 3.5%~18.3% （n=6） and 2.2%~13.8% （n=3）, respectively. Conclusion: The simple pretreatment and high sensitivity satisfied the fast and accurate detection requirement, meanwhile it is suitable for qualitative and quantitative analysis of perfluorinated compounds in animal-derived food.

Abstract:Objective: A simultaneous determination method was established for detecting 19 kinds of quinolones and sulfonamides in aquatic products simultaneously, by using QuEChERS combined with UPLC-MS/MS. Methods: Samples were extracted with 1.0% formic acid acetonitrile solution, ultrasonic for 1 min, and purified by QuEChERS multi-function needle filter. The sample purification and filtering were performed simultaneously. The Mass spectrometry was conducted by using positive (ESI+) electrospray ionization and multi-reactions monitoring (MRM) models, with external standard method. Results: The detection limit of 19 kinds of sulfonamides and quinolones is from 0.5 to 1.0 μg/kg. Compared with the national standard method, the detection sensitivity is improved. The added recoveries were from 81.0% to 113.0%, and the relative standard deviation (RSD) were from 0.2% to 11.7%. Conclusion: This method assisted ultrasonic extraction and QuEChERS, enhanced the efficiency of measuring quinolones and sulfonamides in aquatic products. It is a simple, rapid, sensitivity, accurate method, which provides an efficient technical means for daily monitoring of sulfonamides and quinolones in large quantities of aquatic product samples.

Abstract:Objective: In order to analyze the risk of pesticide residues in D. officinale, a method for rapid determination of 56 pesticide residues in D. officinale by a kind of ultrafiltration purification column（MPFC-QuEChERS） combined with ultra-performance liquid chromatography- tandem mass spectrometry（UHPLC-MS/MS）was developed. Methods: The samples were extracted with acetonitrile contained 0.1% formic acid, salted out, shaken, centrifuged, and single-step purified by a MPFC-QuEChERS purification column. Mass spectrometer was operated in the positive and negative ion mode using select reaction monitoring for qualitative and quantitative analysis. Results: The result showed that, the 56 kinds of pesticides showed good linearity when they were in 1.0~250.0 μg/L （R²＞0.99）. The limits of detection （LOD） was 1～5 μg/kg. Three levels of 1, 2 and 10 times of LOQ were added to the sample, the average recovery of each substance in D. officinale was 75.1% to 107.0%, of which the RSDs were 2.7%～18.9%. Conclusion: This method was used to detect pesticide residues in 20 batches of D. officinale. The results showed that 6 kinds of pesticides were detected in 5 samples with the contents ranging from 0.066 7 mg/kg to 1.872 mg/kg. The method is simple, fast and efficient, and could be used for rapid screening and analysis of pesticide residues in D. officinale.

Abstract:Objective: In this study, ultra performance liquid chromatography-high resolution quadrupole time of flight mass spectrometer (UPLC-Q-TOF/MS) was established to determine β-sitosterol, brassicasterol, and campesterol in camellia oleifera seed oil. Methods: Using 6-ketocholestanol as the internal standard and performing sample extraction by heating it for 30 min and refluxing it with 50 mL ethanol. After centrifugation and layering, three sterols were separated by Xbridge BEH C₁₈ (100 mm × 4.6 mm, 2.5 μm) Chromatographic column elution. Finally, ionized by atmospheric pressure chemical ionization source and analyzed by positive ion mode. Results: The internal standard curves of the three sterols showed an observable linear relationship in the range of 0.1～10.0 mg/L, while the correlation coefficient R² was both greater than 0.999 2. The average recoveries at 0.5, 1.0, 2.0, and 10.0 times of background value were in the range of 84.5%～99.5%. The relative standard deviation (RSDs) was ranged from 3.92% to 7.44%. Moreover, the limits of detection were 1.0 mg/kg and the limits of quantitation were 3.0 mg/kg, respectively. Conclusion: The method was simple in operation, low in solvent consumption, and toxicity. It had good recoveries and reproducibility that could be applied for the accurate determination of three sterols in camellia oleifera seed oil.

Abstract:Objective: A method for the determination of aminophylline residues in edible tissues （muscle, liver and kidney） of pigs by solid-phase extraction combined with high performance liquid chromatography-tandem mass spectrometry was established. Methods: After extracted by methanol, the aminophylline was purified by PRiME HLB solid phase extraction column in one step, and then separated by a C₁₈ chromatographic column. 0.1% formic acid solution and acetonitrile were invoked as the aqueous phase and the organic phase for gradient elution, respectively. Electrospray positive voltage ionization and multi reaction monitoring （MRM） mode are used for compound detection, and matrix matching standard was used for quantification. Results: The analysis of aminophylline drugs was completed within 3.5 minutes, and the results showed good linear relationship （R＞0.998 0） on different matrices in the concentration range of 0.05~1.0 μg/mL. The average recoveries ranged from 87.2% to 101.3%, and the relative standard deviations ranged from 0.7% to 6.2% （n=6）. The detection limit was 2 μg/kg and the quantification limit was 5 μg/kg. Conclusion: The method which is simple and efficient, has good repeatability and high sensitivity. It is suitable for qualitative and quantitative analysis of aminophylline drug residues in edible tissues of pigs.

Abstract:Objective: This study aimed to improve the safety supervision of cadmium in milk samples. Methods: A liquid-liquid microextraction method based on hydrophobic deep eutectic solvent （DES） was developed for the determination of cadmium in milk samples by graphite furnace atomic absorption spectrometry. The types of deep eutectic solvents were selected for high extraction efficiencies and it was found that DES composed of thymol and lactic acid at the molar ratio of 1∶1 provided higher extraction efficiency. In addition, several important experimental conditions including the volume of DES, sample pH value, the pretreatment methods of samples were optimized. Results: Under the optimized conditions, Cd had good linearity in the range of 0～3.0 ng/mL, and the correlation coefficient was 0.998. The detection limit was 0.02 μg/kg. The recoveries ranged from 94.7% to 113.0% with relative standard deviations （RSD） of 0.38%～7.00%. Conclusion: With the advantages of simplicity, rapidness, exactness and low detection limit, this method could be used for the detection of cadmium in milk samples.

Abstract:Under the background of the new era, the traditional food safety risk management model has exposed its fragility and shortcomings. It is necessary to explore the long-term management mechanism of food safety risk management. From the perspective of resilience governance, the framework of resilience governance of food safety risk is constructed, and the multiple consistency of resilience governance and food safety risk governance in terms of value, subject and mechanism is further analyzed. Finally, under the guidance of resilience governance, this paper puts forward a practical path to build a multi-dimensional coordination mechanism, intelligent governance operation mechanism and public participation mechanism for food safety risk governance.

Abstract:Objective: In order to improve the energy efficiency of the transcritical two stage CO₂ refrigeration system, the conventional exergy analysis and advanced exergy analysis of the system were conducted. Methods: Advanced exergy analysis provides more valuable information on the interaction between system components and the potential for component improvement by splitting the exergy destruction into endogenous/exogenous and unavoidable/avoidable parts. Results: The results indicated that the transcritical two stage CO₂ refrigeration system had significant potential for efficiency improvement. The priority of the optimized components from conventional and advanced exergy analysis was different. The advanced exergy analysis showed that performance optimization of the high-pressure stage compressor, low-pressure stage compressor and evaporator were the focus of improving system energy efficiency. Conclusion: The endogenous avoidable exergy destruction of the high-pressure stage compressor, low-pressure stage compressor and evaporator accounted for 20.9%, 15.2% and 36.5% of the endogenous avoidable exergy destruction of the system, respectively. The improvement of the high-pressure stage compressor, low-pressure stage compressor and evaporator are able to reduce their exergy destruction by 58.8%, 49.3% and 90.2%, respectively. The conventional exergy analysis cannot provide such recommendations.

Abstract:Objective: In order to deal with the impact of cyber attack on the cyber-physical system of food picking robot. Methods: A method for states estimation and attacks detection of food picking robot system based on interval observer was proposed. Firstly, the digital model of the food picking robot located in the cyber-physical system was established, using Lagrange method to establish the dynamic equation of the manipulator and convert it into the state-space model, the network attacks model was constructed according to the feedback control strategy. Considering the nonlinear characteristics and noiseand applying the generalized system theory was applied to transform sensor attack into the system state, and the interval observer was designed as the attack detector, and the stability of errors system was proved. Results: The simulation results showed that observer output was close to the given real signal. The proposed method was correct and effective. The sensor attack can be reconstructed and the actuator attack can be detected from interval estimation results. Conclusion: The proposed method can realize states estimation and actuator attacks detection of food picking robot in cyber-physical system environment.

Abstract:Objective: To solve the problem of unstable rice output quality caused by the lack of information exchange and coordinated control between equipment in the rice processing system. Methods: Based on the industrial internet of things technology, a five-layer architecture of the rice processing system was constructed, and the solutions to the technical problems existing in the network layer, decision layer and control layer of the architecture were proposed for the corresponding layer problems such as the wireless sensor network model based on machine vision, the fuzzy self-tuning control model based on differential evolutionary algorithm and the rubber roller synchronization control method of the huller. The hardware and software of the system were designed, the actual transformation of the hulling and milling section was carried out, and then early indica rice grains were selected for processing tests. Results: Compared with the traditional processing, the improved rice processing system increased the browning rate about 1%, the whole fine rice rate by about 1%, and the production energy consumption is reduced about 15%. Conclusion: The researched rice processing system based on IOT technology has implications for improving the intelligent transformation of process processing systems such as rice processing.

Abstract:Objective: In order to solve the problem of manual weighting of dragon fruit, including time-consuming, laborious and expensive, an automated weight estimation method based on machine vision and machine learning was proposed in this research. Methods: Firstly, 106 dragon fruits were weighed, recorded and photographed, and images of dragon fruits were constructed. Secondly, binary images were obtained after denoising and segmentation. Moreover, the three features of pixel area, major axis pixel length and minor axis pixel length of dragon fruits were extracted on the basis of binary images. The three features of each image and their corresponding weights were combined into a set of data, which was divided into training set and test set according to the ratio of 7∶3. Finally, the training set was input into the Gradient Boosting, Random Forest, K-Neighbors and Artificial Neural Networks machine-learning models for training, and the test sets were used for model evaluation. Results: The evaluation index of the Artificial Neural network performed well compared with other models, with R² of 0.986 and RMSE of 13.091. Conclusion: The experimental result demonstrates that the method proposed in this research can accomplish the weight estimation of dragon fruit effectively, and meet the weight estimation requirements of dragon fruit.

Abstract:Objective： Explore the effects of vibration mill's vibration mass on superfine grinding performance of wheat bran. Methods： A series of vibration impact grinding experiments of wheat bran was carried out by adjusting the grinding medium mass and wheat bran mass, respectively. Results： When the wheat bran mass was unchanged, the yield of wheat bran superfine powder showed a non-linear characteristic of first increasing and then decreasing with the increase of the quality of the grinding medium, and the maximum difference rate reached 123.53%. The quality of wheat bran micro powder also increased firstly and then decreased with the increase of grinding medium mass. However, when the grinding medium mass was unchanged, the yield of wheat bran superfine powder showed characteristic of first decreasing and then increasing with the increase of the quality of the grinding medium, and the maximum difference rate reacheds 588.69%. With the increase of wheat bran mass, the quality of wheat bran micro powder decreased firstly and then increased. It was also found that the sensitivity of wheat bran superfine powder yield to wheat bran mass was higher than that of wheat bran superfine powder yield to grinding medium mass. Conclusion： The grinding medium mass and wheat bran mass of vibration mill have significant effects on the superfine grinding of wheat bran, but the effect levels are different.

Abstract:Objective: To solve the problems caused by the manual sampling inspection in the field of food packaging, such as difficult to operate continuously for a long time, easy to miss and wrong detection, and unreliable detection accuracy and stability. Methods: In this paper, a machine vision-based vacuum sealed texture detecting method for transparent packaging bag was proposed to replace manual detection. The image was preprocessed by algorithms such as ROI extraction, affine transformation and local binary pattern to highlight the texture features. On this basis, the gray level co-occurrence matrix was used to analyze the features of "good" and "defective" sealing texture images. The parameters of gray level co-occurrence matrix were set and the uniformity of texture features was associated with the feature quantity of the parameters of gray level co-occurrence matrix. Finally, the parameters of gray level co-occurrence matrix was used as the input of SVM classifier, and the sealing defects were identified and classified through calculation. Results: This online detection method compares the defect detection results of the vacuum sealing of transparent packaging bags with the manual quality results up to 97.5%. Conclusion: This method has high detection accuracy and good practicability, and can meet the needs of online detection.

Abstract:This paper discusses the application strategy and development trend of motion graphic design in FMCG food packaging and brand visual identity system in the digital context. By analyzing the classic cases of global and regional FMCG brand marketing, this paper discusses the application strategy of motion graphic design in FMCG packaging and brand identity system in the digital context. The results show that motion graphic design with its artistic expression, inclusiveness of multiple technologies and styles, efficient and accurate information transmission efficiency, and flexible production mode, can enhance the identification and ductility of FMCG food packaging design, and is also a necessary condition for maintaining the strong competitiveness of FMCG food brands.

Abstract:Objective: In order to solve the problem of complicated state in the process of pre-cooling packaging of fluid ice, it provides a basis for the application of fluid ice in the storage and transportation of fruits and vegetables, fresh-keeping and so on. Methods: Taking broccoli as the research object, the heat transfer model of pre-cooling broccoli with fluidized ice was established. The change of temperature field and ice crystal particles during the process of precooling and storage of broccoli was simulated by CFD. The effects of fluid ice crystal integral number and mass ratio of fluid ice on broccoli precooling and storage temperature were analyzed, and the verification experiment was carried out. Results: The larger the volume fraction of ice crystal, the more uniform the distribution of ice crystal particles and the better the precooling uniformity; When the mass ratio of fluidic ice was 100%, the fluidic ice could meet the requirement of precooling temperature. Conclusion: By adjusting the volume fraction and mass ratio of fluid ice and reducing the redundancy of the upper space inside the packaging, the pre-cooling effect of broccoli can be improved and the storage time can be extended.

Abstract:Objective: The purpose of the study was to investigate the antibacterial mechanical properties of PLA nanofiber film loaded with PAE and its preservation effect on chilled mutton. Methods: By loading different amount (0, 12.5, 25, 50, 100 μL/20 mL) of electrospinning solution perillaldehyde (PAE) in polylactic acid (PLA) matrix, the antibacterial nanofiber film packaging with certain water absorption properties was prepared through electrospinning technology. The appearance and mechanical properties of PAE-PLA packaging film and physical-chemical indexes of mutton during preservation were analyzed via scanning electron microscopy and electronic universal testing machine. Results: With the increase of loading amount of PAE amount, the diameter, breaking elongation and tensile strength of PAE-PLA nanofiber films increased first and then decreased, which indicated that the addition of PAE can change the surface charge density of electrospinning solution. Therefore, the diameter of nanofibers was affected, and thereby the breaking elongation and tensile strength of nanofiber packaging films were changed. When the added PAE concentration was 50 μL/20 mL of electrospinning solution, the PAE-PLA nanofiber films showed uniform distribution, a largest diameter (370 nm) with good mechanical properties, i.e., elongation at break of 68.72% and tensile strength of 1.80 MPa. After 12 days of storage, the total bacterial count and volatile salt nitrogen of mutton packaged with PLA membrane loaded with 50 μL PAE were 5.52 lg(CFU/g) and 12.55 mg/100 g, respectively, which are significantly lower than the critical values of fresh meat and spoilage meat [6.0 lg(CFU/g) and 15.00 mg/100 g] (P＜0.05). Conclusion: PAE-PLA film loaded with 50 μL /20 mL PAE solution has good mechanical properties and antibacterial properties.

Abstract:Objective: To clarify the effect of controlled atmosphere on preservation of water bamboo. Methods: Cold storage under air was used as control, the sensory quality, texture （firmness, chewiness and shear force）, color （L^* value and W_H value）, the contents of soluble protein, lignin and cellulose, as well as the activities of phenylalanine ammonia lyase （PAL） and polyphenoloxidase （PPO） were determined under four different gas components （CA1: 2% O₂+7% CO₂+91% N₂, CA2: 5% O₂+10% CO₂+85% N₂, CA3: 5% O₂+7% CO₂+88% N₂, CA4: 2% O₂+10% CO₂+88% N₂）, then stored at 0 ℃ with the relative humidity （RH） of 85% ～ 90%. Results: Controlled atmosphere （CA） treatment could significantly slow down the decline of sensory quality, L^* value and W_H value of water bamboo and the consumption of soluble protein （P＜0.05）. Among these CA treatments, the effects of CA2 treatment on preservation was the best. After 90 d storage, the PAL and PPO activities of CA2 treatment were significantly lower than those of control group, CA1 and CA3 （P＜0.05）, but there was no significant difference with CA4. Moreover, the accumulation of lignin and cellulose were inhibited, but the inhibition effect of CA2 treatment on lignin and cellulose were lower than that of CA3. The firmness and chewiness of CA1 treatment were significantly higher than other treatments （P＜0.05）, but the shear force was lower than that of CA2. Conclusion: The gas components of 5% O₂+10% CO₂+85% N₂ effectively inhibited the quality deterioration of water bamboo, showing the best effect on commodity quality after 90 days of storage, providing theoretical basis and technical support for storage of water bamboo.

Abstract:Objective: The storability and storage quality of three pear varieties were evaluated to provide theoretical support for variety breeding and fresh-keeping technology. Methods: Zaoshengxinshui, HJ18 and HJ67 pear with similar genetic background were used as test materials. Fruit with the same maturity were stored in a cold storage with a temperature of （1.0±0.5） ℃ and a relative humidity of 85%～90% for 60 days. The fruit texture, sugar and acid and volatile substances were determined every 10 days, divide storage period and quality based on clustering, principal components and time series analysis. Results: The results showed that the fruit texture, sugar, acid and volatile substances of the three pear varieties were regulated by storage time, and there was a certain correlation among different indexes. Fourteen quality evaluation parameters could be simplified into 8 indexes: firmness, chewiness, compactness, brittleness, elasticity, malic acid, citric acid, soluble solids content （SSC） and fructose. The contribution rate of sensors S2, 6, 7, 8 and 9 was larger. Based on fourteen quality indexes, HJ67 was in a relatively independent space with Zaosheng Xinshui and HJ18 during storage. Based on the response values of ten sensors, the three varieties had spatial intersection, which had not been effectively distinguished. The storage time of three pear varieties was divided into different intervals, among which HJ67 was divided into four periods: 0~20 days, 30 days, 40~50 days and 60 days based on texture, nonvolatile and volatile substances. Conclusion: It is concluded that the texture, sugars and acids contents and volatile matter of HJ67 are significantly different from those of Zaoshengxinshui and HJ18, that has a rich flavor. The change of fruit texture of three pear varieties can be well fitted by exponential equation, and the change of sugar and acid content can be well described by nonlinear equation. The prediction errors of the two prediction models are low. Based on principal component analysis, cluster analysis and time series analysis, the storage period and comprehensive quality of three pear varieties can be comprehensively and objectively evaluated.

Abstract:Objective: This study aimed to investigate the effect of Antarctic krill oil on zebrafish model of depression. Methods: The zebrafish (Danio rerio) model of depression was induced by 40 mg/L reserpine, and five groups, i.e., blank control group, model group, fluoxetine group, low-dose krill oil group and high-dose krill oil group were investigated and compared, buy using new tank test (NTT) and light dark box test (LDB). The central nervous system serotonin (5-HT), dopamine (DA), monoamine oxidase A (MAO-A) Interleukin-6 (IL-6), tumor necrosis factor α (TNF-α) and systemic cortisol (COR) levels of the five groups were analyzed. Results: Reserpine 40 mg/L caused depressive behavior in zebrafish, while the addition of prawn oil reduced the this behavior, by increasing the levels of monoamine neurotransmitters including 5-HT and DA in the brain and decreasing the levels of MAO-A, IL-6 and TNF-α proinflammatory factors and systemic COR levels. Conclusion: Antarctic krill oil can improve the depression of zebrafish by reducing neuroinflammation and regulating neuroendocrine.

Abstract:Objective: This study aimed to provide theoretical basis for hardy kiwifruit quality improvement and rational utilization. Methods: Taking the main variety 'Longcheng No. 2' and line 'Haijia' as experimental materials, the changes of basic quality indexes, contents of total phenolics and flavonoids were analyzed during fruit development. On this basis, the antioxidant capacities were comprehensively evaluated by three assays (FRAP iron reducing ability, ABTS radical scavenging ability and DPPH radical scavenging ability). Furthermore, the differences of total phenolics and antioxidant capacities in different parts of fruit were compared. Results: ① The contents of soluble solids, titratable acids and Vc in the fruits of the two varieties (lines) showed a trend of continuous increasing during fruit development. ② The chlorophyll contents of two varieties (lines) both declined constantly at the early stage of fruit development, and then increased continuously from 64 days after blooming. The carotenoids of two varieties (lines) also increased continuously from 64 days after blooming, meanwhile, the anthocyanins of 'Haijia' increased gradually. ③ The contents of total phenolics, flavonoids and three antioxidant capacities all decreased significantly during fruits ripening. The correlation analysis showed that among all quality indexes, total phenolics and flavonoids had extremely significant positive correlations with the three antioxidant capacities. ④ In mature fruits, the contents of total phenolics and flavonoids in the peel were significantly higher than those in the flesh, which indicated strong antioxidant capacities. Conclusion: The antioxidant capacities of two varieties (lines) of hardy kiwifruit decreased significantly during fruit development. Moreover, the content of total phenolics, especially flavonoids are the main components to affect antioxidant capacities during fruit development. In the different fruit parts, the peel has higher antioxidant capacities, but it is also the main source of astringency.

Abstract:Objective: The study aimed to research the physicochemical properties, structure, antioxidant activity and hypoglycemic activity of different fractions of polysaccharide of goldenmelon. Methods: Four kinds of goldenmelon polysaccharides (CP-40, CP-60, CP-70, CP-80) were obtained by graded purification of water extraction and alcoholic precipitation. Their molecular weight, monosaccharide composition, group composition, antioxidant and hypoglycemic activities were investigated by high performance liquid chromatography and fourier transform infrared spectroscopy. Results: With the increase of ethanol volume fraction, the total sugar content increased and the glucuronic acid content decreased. The molecular weights of these four polysaccharides were different, which indicated by the same composition of monosaccharides but different composition ratios, and they all had the characteristic absorption peaks of polysaccharides. The antioxidant capacity and hypoglycemic activity of the polysaccharides in vitro had obvious quantity-effect relationships, CP-70 had the strongest antioxidant effect on DPPH radicals, hydroxyl radicals and superoxide anions scavenging than other groups, while CP-80 had the best hypoglycemic activity since it had the strongest inhibitory effects on α-glucosidase and α-amylase. Conclusion: The polysaccharide of goldenmelon had good antioxidant properties and hypoglycemic activity.

Abstract:Objective: Response surface methodology was used to optimize the extraction process of steroidal glycosides from Cynanchum auriculatum Royle ex Wight by complex enzymatic method, and its effects on alcohol dehydrogenase activity and human hepatoma cell HepG2 were analyzed. Methods: Four experimental factors; enzymolysis duration, temperature, compound enzyme dose and pH were used as responses to a single-factor experiment of the Response Surface Methodology on the steroidal glycoside yields, using perennial C. auriculatum as the target material. The alcohol-induced hepatocyte damage model of HepG2 was used to investigate the contents of ALT, LDH, and GSH and changes in cell shape. Results: The results show that the optimum extraction conditions of steroidal glycoside enzyme were obtained at an enzymolysis duration of 100 min, a temperature of 46 ℃, enzyme dose of 1.30% and pH of 5.0. Consequently, the actual extraction rate of （2.80±0.04）% was achieved using the optimized process conditions, which was close to the expected value. Compared with the model group, it significantly suppresses the growth of ALT and LDH while increasing the amount of intracellular GSH, and the cell damage was restored. Conclusion: The compound enzyme method can effectively extract the steroidal glycosides of Cynanchum auriculatum Royle ex Wight; steroidal glycosides of C. auriculatum have hepatoprotective effect.

Abstract:Objective: Replacing wild resources with artificially cultivated Nostoc commune to protect the natural environment. Methods: Compare the biochemical composition, texture characteristics, and sensory evaluation of indoor, outdoor cultivation and wild N. commune, while using outdoor cultivation of Nostoc sphaeroides as a control in the above three aspects. Results: The ratio of dry weight to wet weight of wild N. commune was the largest （2.42%）, and its hardness and elasticity were the highest, which were 1.184 N and 78.5%, respectively. The content of phycoerythrin and polysaccharide of outdoor N. commune were the lowest, which were 0.19% and 24.45%, respectively. The allophycocyanin and protein contents of wild N. commune were the lowest, which were 0.33% and 20.33% respectively. The chlorophyll and phycocyanin contents of indoor N. commune were the highest, which were 0.82% and 2.75%, respectively. At the same time, the sensory evaluation results showed that there was no significant difference in the taste of N. commune among the different growth patterns （P<0.05）. Conclusion: Artificial cultivated N. commune can completely replace wild resources for consumption and further processing of products.

Abstract:Objective: This study aimed to develop konjac rice noodles products with low glycemic index. Methods: The fresh wet rice noodles was made by adding 20%, 10% and 5% konjac refined flour into rice noodles, respectively. The effects of the addition of konjac refined flour on the texture, cooking performance, and sensory quality of rice noodles were studied by texture analyzer and rapid viscosity analyzer. The starch hydrolysis rate, digestion rate, and glycemic index of konjac rice noodles were studied by in vitro digestion model. Results: The cooking loss rate and turbidity of 5% konjac rice noodles were significantly reduced, and there was no significant difference in sensory scores between them and white rice noodles. Compared with white rice noodles with a high estimated glycemic index, the estimated glycemic index of rice noodles with 5% konjac flour significantly decreased to 60.49, and it has a higher nutritional value. Conclusion: The konjac rice noodles product with 5% konjac refined flour can significantly reduce the glycemic index of rice noodles, and its edible quality is as same as the traditional white rice flour products.

Abstract:Objective: The objective of this study was to develop high-quality non-fried whole shiitake (Lentinus edodes) crisps due to having high oil content of vacuum fried L. edodes crisps which inevitably pose health risks after long-term use. Methods: Based on uniform design, instant controlled pressure drop (DIC) was used to investigate the influences of moisture content after heat pump pre-drying, puffing temperature and vacuum drying temperature on the puffing degree, rehydration ratio, total color difference, hardness and crispness of L. edodes crisps. The polynomial regression model was established by using a weighted comprehensive score method, and it was optimized and verified accordingly. Results: The optimum parameter combinations of L. crisps during DIC processing were moisture content after heat pump pre-drying of 35.63%, puffing temperature of 100 ℃, vacuum drying temperature of 64.17 ℃. Under the control of these optimal parameter combinations, the puffing degree of L. crisps was 69.34%, total color difference was 20.68, hardness was 108.16 N, and crispness was 75.79. Conclusion: Uniform design combined with response surface methodology can be used to optimize processing parameters of DIC crisps and obtain high quality non-fried L. crisps.

Abstract:Objective: This study aimed to improve the oxidation, exploitation, and utilization of pumpkin seed oil (PSO). Methods: Pea protein isolate (PPI) -Tannic acid (TA) stabilized Pickering emulsion with Maltodextrin (MD) was used as the filling material, and prepared pumpkin seed oil microcapsules by spray drying. Results: After spray drying the Pickering emulsion, the smooth surface of the medium shell structure of microcapsule powder can be obtained. By increasing TA concentration, microcapsules showed smaller particle size [(32.00±0.28) μm], lower moisture content [(1.970±0.043)%], and higher bulk density [（0.725±0.014) g/cm³]. The FFA release rate of pumpkin seed oil microcapsules with different TA content was in the range of 39.63%～69.91%, and it slowed down when TA concentration increased. Compared with the PSO encapsulated in PPI, the PPI-TA composite used as the shell material improved the thermal stability, oxidation resistance and oxidation stability of PSO. Conclusion: These results indicated that PPI-TA-MD microencapsulation technology can improve the antioxidant capacity and oxidation stability of PSO.

Abstract:Milk contains a variety of bioactive ingredients, such as lactoferrin and immunoglobulin, which are beneficial to health. Reducing the loss of these proteins during processing has always been the focus of attention. Dynamic high-pressure processing technology, also known as ultra-high-pressure homogenization (UHPH), is one of the relatively novel processing technology means. In this review, the research progress of the heat load intensity and the retention of key nutrients in the processing of dairy products were summarized from the aspects of Maillard reaction products, lactoferrin, immunoglobulin and other bioactive ingredients and vitamin loss. Moreover, the development direction of ultra-high-pressure homogenization in dairy product processing was prospected.

Abstract:Shelling rate and kernel breaking rate are the two key indicators of shelled materials, and mechanical shelling is one of the important methods to improve these key indicators. In this paper, the common mechanical shelling methods, mechanical shelling types, mechanical shelling principles and development status of shelling materials were analyzed. The advantages and disadvantages of mechanical hulling equipment were summarized, and suggestions were made for the problems existing in the current application of mechanical hulling.

Abstract:Polyphenol is one of the characteristic physical and chemical indexes of edible plant enzyme, which has the effects of anti-oxidation, reducing fat and anti-tumor. This paper reviews the composition of polyphenols in food plant enzyme products, the factors affecting the formation of polyphenols in food plant enzyme products, the health care effects of polyphenols, and the further research directions of polyphenols in edible plant enzymes are also prospected.

Abstract:Grape seed extracts, due to its strong antioxidant activity, is commonly used as a nutritional supplement or dietary supplement. It can be used to prevent metabolic diseases such as inflammation, tumors, and atherosclerosis. This article provides an overview of the nutritional composition and biological functions of grape seed extracts, summarizes the latest research findings on the bioactive ingredients in grape seed extracts in terms of antioxidant, anti-inflammatory, anti-tumor, antimicrobial, and anti-atherosclerosis effects, and discusses the shortcomings and future research directions in grape seed extracts research.

Abstract:Post-acidification is one of the most important factors affecting the sensory quality, flavor characteristics and stability of yogurt during shelf-life. Non-thermal treatments are novel methods to control post-acidification, which can maintain the original nutritional properties and sensory quality of food to the maximum extent. In this paper, the mechanism of post-acidification of lactic acid bacteria was reviewed. The mechanism and recent research progress of non-heat treatment processes such as ultra-high pressure, ultrasound, pulsed electric field, CO₂ treatment, irradiation were analyzed and provided theoretical guidance for the development and industrial application of non-heat acid control technology.