Abstract:As one of the most important physicochemical properties of dietary fiber powders, the water-interacting property is closely related to their technological properties and physiological functions in the food system. However, systematic research is unavailable on the relationship between the water-interacting properties and the composition and particle structure of dietary fiber powders. Therefore, the water-interacting properties of dietary fiber powder and these dependence on composition and particle structure by correlation analysis were investigated, based on the determinations of the hydration properties (water holding capacity, swelling capacity), hygroscopicities (initial absorption rate, absorption time, maximum absorption rate), dietary fiber contents (total dietary fiber, soluble dietary fiber and insoluble dietary fiber), and particle structure (particle size, span, specific surface area, pore volume, pore size) of 40 kinds of dietary fiber powders. The results showed that the water holding capacity of dietary fiber powder was positively correlated with its swelling capacity, while the correlation between its hydration property and hygroscopicity was not significant. In contrast, the hydration property was more depended on the fiber composition than the particle structure. The water holding capacity of the dietary fiber powder were consistent with the uniformity of the particle size. However, the hygroscopicity had no significant correlation with neither the composition or particle structure.

Abstract:Hemolysis test, coagulase titer assay, and enzyme-linked immunoreaction method were used to detect the expression changes of hemolysin, plasma coagulase, and total enterotoxins after treating with punicalagin. Reverse transcription real-time fluorescence quantitative PCR was used to detect the expression of virulence-related genes. The results showed that punicalagin could significantly reduce the production of α-hemolysin, but the inhibition effect was not concentration-dependent. At the concentrations of higher than 1/4 MIC, punicalagin could decrease the expression of plasma coagulase. At the concentrations of higher than 1/2 MIC, punicalagin significantly reduced the production of total enterotoxins. Punicalagin also significantly reduced the transcription of enterotoxin gene sea, hemolysin gene hla, and regulatory gene agrA. The relative expression levels of the three genes were 3%, 5% and 5% of the control group at 1/8 MIC of punicalagin, respectively.

Abstract:In order to enrich lactic acid bacteria resource from soy sauce residue, Lactococcus lactis from soy sauce residue were screened and identified by physiological and biochemical tests and 16S rRNA gene sequence analysis, and their tolerance to gastrointestinal environment were further studied. Four strains of lactic acid bacteria were isolated from soy sauce residue. Three of them were identified as Lactococcus lactis subsp. hordniae, HT127, HT223 and HT227, respectively. One was identified as Lactococcus lactis subsp. lactis and named HT122. The results of growth curve showed that the growth of four strains were similar, and the logarithmic growth period was 2~12 h after inoculation. The results of gastrointestinal fluid tolerance test showed that strains HT233，HT127，HT227，HT122 could tolerate the simulated gastric juice, with live bacterial rates of (94.85±0.05)%, (81.67±0.25)%, (77.99±0.58)%, (58.57±0.57)% respectively. Meanwhile, the live bacterial rates of HT122, HT127, HT223, HT227 were (77.78±0.68)%, (67.42±0.72)%, (34.25±0.08)%, (22.28±0.18)% after cultured for 8 h in the simulated intestinal juice. All the results suggested that HT127 might show the good tolerance to the simulated gastrointestinal environment and could be benefit to the expansion of food-borne lactic acid bacteria resource bank.

Abstract:Preparation of peptides chelated calcium from silkworm pupa peptides, taking the soluble calcium content as the main index, and considering the chelation and yield rate, the effects of reaction pH, temperature, time, and peptide-calcium ratio were examined. On the basis of single factor experiment, Box-Behnken central composite design was utilized, and the optimal conditions were as followed: reaction time 80 min, reaction temperature 73 ℃, pH 10, peptide calcium ratio 3.41.0. Under this condition, the soluble calcium content of the silkworm pupa peptide chelated calcium was 14.51%. Through the UV absorption and infrared spectroscopy and SEM analysis, it showed that the silkworm pupa peptides and calcium ions chelation occurred, and the phosphate group, carboxyl group and amino group participated in the reaction.

Abstract:Head space solid-phase microextraction (HS-SPME) coupled with chromatography-mass spectrometry (GC-MS) method was developed to study the effects of different tempera-ture of the heater on the composition and content of aroma components in the test samples of different batches of cigarettes. The results were as follows: ① A total of 35 core aroma components were detected in two batches of finished cut tobacco, of which batches X and Y contained 30 and 34 kinds respectively; ② 3-methyl-3-buten-2-one, 2-hexene-1-alcohol, 2-(butoxyethoxy)ethanol, Methyl palmitate and 3,5-dimethylphenol were undetected components in X, while 3-methyl-1,2-cyclopentadione was undetected components in Y. 1,2-propanediol was the highest content of aroma substances; ③ F-test showed that the differen-ce in the content of aroma components in X and Y was resulted in by the temperature of heater and the temperature set at 270 ℃ was more conducive to retain aroma components in tobacco.

Abstract:To analyze the taste substances of cooked Tibetan pork, Sanmenxia black pork and Du changda white pork, the three raw materials were separately cooked, and then the free amino acids and nucleotides were determined by liquid chromatography, and the fatty acid content was determined by gas chromatography. The taste substances were tested by electronic tongue. SPSS 19 was used to analyze the taste substance difference of the three porks. The results showed that the free glutamic acid content of cooked Sanmenxia black pork was the highest, and the inosinic acid content of cooked Tibetan pork was the highest. Compared with the Du changda white pork, the umami taste of cooked Tibetan pork and Sanmenxia black pork was stronger. Content of 5′-adenine ribonucleotide (5′-AMP) and 5′-hypoxanthine nucleotide (5′-IMP) of cooked Tibetan pork was the highest, reaching 192.41 mg/100 g, followed by Sanmenxia black pork and Du changda white pork, indicating the cooked Tibetan pork has a stronger umami taste. The total fatty acid content of cooked Sanmenxia black pork was the highest, reaching（2.25±0.02） mg/g. The saturated fatty acid content of cooked Sanmenxia black pork was the highest, followed by Tibetan pork, the content of cooked Du changda white pork was the lowest. The first principal component contribution rate (PC1) of the three cooked porks was close, indicating that the three cooked porks had similar taste substances. The umami substances of cooked Tibetan pork, Sanmenxia black pork and Du changda white pork were different, but the taste substances were similar.

Abstract:In order to explore the color, fragrance and taste quality of Yunnan broken black tea, it provides a reference of the quality characteristics of domestic broken black tea in this study. This study collected 14 Yunnan broken black tea and analyzed the quality from sensory evaluation, color difference, aroma components, and physical and chemical ingredients. The results showed that the 14 sample tea soups were mainly red and bright, and the color differences L*, a*, and b* were -22.50 to -12.28, 9.09～23.80, 62.09～164.40, respectively. The amounts of TF, TF-3G, TF-3'G and TFDG were 0.146%～0.209%, 0.108%～0.225%, 0.041%～0.109%, 0.056%～0.177%; respectively. The aroma was pure, and the main aroma component detected by GC-MS was benzaldehyde (1.291%～11.747%), linalool oxide I (1.705%～6.394%), linalool oxide II (4.950%～14.094%), linalool (10.070%～45.471%), and methyl salicylate (7.255%～28.142%). The taste is mainly strong, the amounts of water extract, polyphenols, and free amino acids are 30.511%～36.422%, 10.198%～17.280%, 3.022%～4.443%, respectively. The alkaloids and the components of catechin, amino acid and sugar are also important components of the taste quality of tea soup. The sensory quality of Yunnan broken black tea is closely related to the color difference, volatile components, and physical and chemical components. It also shows that the components of tea can reflect the sensory quality characteristics to a certain extent by correlation analysis, and there is a certain correlation between the components and sensory quality. The composition and content of components can reflect the sensory quality characteristics to a certain extent. The level of material content may be related to the origin and processing technology and other factors, which provides a reference for the study of the quality characteristics of domestic broken black tea.

Abstract:In order to understand the relationship between the moisture content of tobacco and its microporous structure, and to provide a theoretical basis for the preservation of tobacco, the dehydration rate over 4 000 min of 26 Tobacco samples including flue-cured tobacco, burley tobacco, oriental tobacco, reconstituted tobacco leaf and expanded cut stems were measured (1 time/min) at a temperature of （22±1） ℃ and a relative humidity of 30% using a tobacco dynamic moisture content monitoring device. The α and β values in the thermodynamic Weibull model were calculated from the dehydration rate. Results: At the same storage temperature, humidity and the same time, the rate of water loss of the reconstituted tobacco leaves and the expanded cut stem samples was the highest, followed by the burley tobacco and the oriental tobacco samples, and the flue-cured tobacco samples were the lowest. The values of α and β in the Weibull model of samples were significantly negatively correlated with the average pore diameter of the microwells. The moisture retention properties of tobacco samples were significantly negatively correlated with the average pore diameter of their micropores.

Abstract:The moisture absorption and moisture retention properties of polygonatum polysaccharides, fenugreek polysaccha-rides, chlorella polysaccharides and ganoderma lucidum polysaccharides were investigated as compared with propylene glycol and water. The results showed that polygonatum polysaccharides had similar moisture absorption properties as propylene glycol, but its moisture retention was significantly better than that of propylene glycol. Therefore, the desorption process of tobacco under low humidity conditions was fitted nonlinearly by common thin-layer drying models. It was found that the tobacco added with polygonatum polysaccharides have the lowest drying rate constant and the slowest moisture retention rate. Low field nuclear magnetic (LF-NMR) results showed that, the addition of polygonatum polysaccharides reduced the physical bound water content where as the chemically bound water content in tobacco was increased. Therefore, polygonatum polysaccharides could be used as a natural and efficient humectant in tobacco to prevent the loss of moisture during storage.

Abstract:A fast determination method was established for content determination of mashed potato in noodles. Studied 170 potato noodles by near infrared spectroscopy and stoichiometry to establish prediction model by PLS. The result indicated that the prediction model based on wave number of 9 403.6～5 446.2 cm^-1, and spectral pretreatment by the standard normal variate transformation (SNV) showed an excellent prediction accuracy. The external validation determinants was 0.956 4, the root mean square error of prediction was 3.73%, the slope was 1.029, and relative prediction deviation was 2.04. The results indicate that near infrared spectroscopy can be used as an efficient way to detect the mashed potatoes content of potato noodles.

Abstract:To prepare monoclonal antibodies against soybean Kunitz trypsin inhibitor (KTI) with good immunological characteristics. BALB/c mice were used to immunize with 50 μg of KTI, the antiserum titer and sensitivity were identified via indirect ELISA and indirect competitive ELISA. The mice which serum has better titer and sensitivity were selected for cell fusing, then he hybridoma cell strain which stabilization secreted KTI monoclonal antibody (mAb) were screened. Thereafter, mAb was prepared by inducing ascites in vivo and identified the immunological characteristics. The result indicated that the NO.1 mouse was confirmed to produce the antibody with the highest titre, IC₅₀ was 157.33 ng/mL. After cell fusing, 4E6-E9 positive hybrid tumor cell lines were obtained, and the 4E6-E9 mAb titer was above 11 638 400, of which subtype was IgG1, with affinity constant 1.45×10⁸ L/mol, IC₅₀ 28.39 ng/mL, and high specificity. Our results demonstrated the mAb had good immunological characteristics, and could provide a good antibody basis for the sensitivity and specificity immunological detection of KTI.

Abstract:To analyse and evaluate the uncertainty in the determination of neotame content in roasted seeds and nuts by UPLC-MS/MS. A mathematical model of uncertainty in the determination of neotame content in roasted seeds and nuts was established, various factors of uncertainty in the whole determination process were studied and evaluated, the components of uncertainty in the method were confirmed and composed. The results showed that the expanded uncertainty was 0.71 mg/kg(k=2) when the neotame content was 7.69 mg/kg, which was greater caused by preparation of standard stock solution and repeatability of determination.

Abstract:Terahertz attenuated total reflection spectroscopy was employed to investigate the terahertz absorption spectra of different concentration glycine solutions within 20~450 cm^-1 at room temperature. There are four clear absorption peaks at 65.56, 127.28, 173.56, 308.55 cm^-1 respectively. The 2^nd derivative spectra and the multiple linear regressions were employed to perform the quantitative analysis of the glycine solution concentr-ation. Randomly combine different wave numbers, the optimum ternary linear regression equation was gained. The R² _Adj was 0.990 3, the Root Mean Square Error (RMSE) was 0.005 7, the Root Mean Squares Error of Prediction (RMSEP) was 1.658 9.

Abstract:An analytical method was developed for the determination of 8 kinds of vitamin E isomer (tocopherol and tocotrienol) in vegetable oil by solvent dilution extraction-ultra performance liquid chromatography. The sample was extracted with acetone. The separation was achieved by using PFP column and an elution with the mobile phases of methanol and water (937) at a flow rate of 0.4 mL/min. The identification and quantitative analysis were carried out with fluorescence detector at an ecxitation wavelength of 295 nm and an emission wavelength of 330 nm. The recoveries ranged from 90.0% to 100%, with the relative standard deviation (RSDs) between 0.28% and 1.22%. The linear range was 0.4～40.0 μg/mL and the correlation coefficient (r) was greater than 0.999. The limits of detection were 4.0 mg/kg for each vitamin E isomer. The method was enough for the analysis of vitamin E in actual samples with wide linear range and high sensitivity.

Abstract:According to the procedure for uncertainty assessment described in JJF 1059.1—2012 “Evaluation of uncertainty in chemical analysis measurement” and CNAS—GL06—2019 “Guidance on evaluating the uncertainty in chemical analysis”, a mathematical model was established, and an analytical method for the determination of uncertainty of morphine, codeine, papaverine, narcotine and thebaine in chafing dish food by LC-MS/MS was established. The results showed that the synthesis of relative standard uncertainty for papaverine, narcotine, thebaine, morphine and codeine were 5.1×10^-2, 5.0×10^-2, 5.8×10^-2, 8.4×10^-2, and 8.5×10^-2, respectively; the main factors affecting the uncertainty of measurement results included the sample recovery rate, the repeatability of parallel experiments, sample extraction, calibration curve fitting, and the configuration of standard working solution. From the uncertainty component of calibration curve fitting, it was revealed that morphine and codeine determined by the internal standard method were obviously superior to the other three substances measured by the external standard method. Consequently, using the internal standard method could reduce the uncertainty caused by different sample matrices.

Abstract:Simultaneous determination of four flavonoids in extracts of the fruits of Rosa davurica pall.(FRDP) by high performance liquid chromatography (HPLC) was carried out, and the in vitro activities of extracts of FRDP, four flavonoids and their compound compatibility were measured by UV method. The results showed that the contents of hyperoside, rutin, quercetin and luteolin of the extract of FRDP were 607.98, 450.63, 187.32 and 12.68 μg/g respectively. The extracts of FRDP, four flavonoids and their compound compatibility all have certain antioxidant activities in vitro, and the activity of extracts of FRDP was stronger than that of compound compatibility. However, both of them were weaker than that of VC. The extracts of FRDP, four flavonoids and their compound compatibility also had the activity of scavenging nitrite, blocking the synthesis of nitrosamine and inhibiting α-glucosidase, and the activity of extract of FRDP was stronger than those of acarbose and compound compatibility。

Abstract:To evaluate the dietary risk level of pesticide residues in muskmelon in Xinjiang and identify the types of pesticide residues with relatively high risks. Based on the research of 127 muskmelon samples of the 2-year-producing in Xinjiang, 60 kinds of pesticide residues were analyzed by chronic, and the acute dietary exposure assessment, and the dietary risk levels were evaluated. Moreover, the usage of veterinary drug residue council sort veterinary drug residue risk matrix, and the pesticide residue in high-risk types were discussed. The results showed that 10 kinds of pesticide residues, icluding phenyl ether metronidazole, chlorpyrifos, chlordimeform, and chlorphenidine, were detected in the melon samples, and the detection rate ranged from 0.79% to 22.05%. The risk of chronic dietary intake (%ADI) and acute dietary intake (%ARfD) of pesticide residues in different populations were significantly lower than 100%. The risk scores of chlorpyrifos, phenyl ether metronidazole, and dinitrile were 24.03, 18.12 and 18.05, respectively, showing higher than those of other pesticide residues. Most importantly, chlorpyrifos and phenyl ether metronidazole were high-risk residual pesticides, and we need to be very careful of the usage of them.

Abstract:Criminal behaviors that endanger food safety have seriously damaged the lives and health of the people. Law enforcement agencies have encountered many problems in the enforcement of crimes against food safety crimes. The emergence of these problems has seriously affected the linkage mechanism between administrative law enforcement and criminal justice. How to base the connection between criminal justice and administrative law enforcement, rationalize the mechanism of linking the two laws, improve the efficiency of law enforcement agencies in combating food safety crimes, thoroughly eradicate food safety issues, and lay a solid foundation for China's economic construction and social harmony and stability, which has become a top priority.

Abstract:At present, based on the predicament of global food safety governance and the requirement of China to promote the improvement of social governance system and the modernization of governance capacity, Chinas food safety management has a high implementation efficiency in the construction of system and the promotion of government-led system practice. However, at the level of food safety governance, there are still some problems, such as the degree of information disclosure to be further expanded, the lack of operability of the food recall system, the disunity of the main body caused by the administrative supervision system, and the lack of a real food safety traceability system. In this regard, we need to adhere to the problem-oriented and demand-oriented basis, and selectively draw lessons from the effective mechanism of food safety management in the United States, from optimizing and constructing an all-round information disclosure system, improving and refining the problem food recall system, rationalizing and integrating the responsibilities of administrative supervision departments, and establishing and implementing food products. The compulsory system of the safety traceability system and other four dimensions are to improve the overall system and refine the implementation mechanism, so as to ensure the realization of the goal of legalization of Chinas food safety governance.

Abstract:The temperature distribution inside the drum of tea cylinder water-removing machine is the main factor affecting the quality of the tea. In view of the defects of the current tea cylinder water-removing machine, including the uneven water-removing and low thermal energy utilization, a tea cylinder water-removing machine was designed with infrared radiation as the heat source in the present study. The infrared heat source was placed in the center of the cylinder. The approach of combining EDEM and Fluent was used to analyze the discrete field, flow field and temperature field during the de-enzyme process The turbulence model and the radiation model were installed in the software Fluent, then the contact model of tea leaves and cylinder was established by the discrete element software EDEM. The temperature distribution of the flow field in the drum and the temperature rise curve of de-enzyme green leaves were obtained through coupled calculation, realizing the numerical simulation of the de-enzyme process, then the simulation results with the same type of electric heating machine were compared. The simulation results showed that the temperature flow field of electric heating structure was evenly distributed in the drum, and the utilization rate of heat energy was low. While filming for the infrared temperature distribution in the flow field in the cylinder was mainly concentrated in the right and bottom rollers, and could put most of thermal radiation on the steamed directly. With the utilization of the high heat energy, the editing device could make the steamed quickly to heat up and warm effect, thus the enzyme activity was passivated in a short time, improving the quality of the tea. The relative error between the measured temperature and the simulated value was about 0.99%, indicated a reasonable parameter setting.

Abstract:In view of the problem of long time and high energy consumption of macadamia nuts of drying, the infrared drying characteristics were analyzed and a mid-infrared dryer was designed. The mid-infrared drying characteristics reasch of macadamia nuts were carried out. The changes of dry moisture and rate were analyzed. The dry-diffusion and activation energy conditions were established and a mid-infrared drying model was established. The results showed that the moisture content of macadamia nuts decreased to 1.36% after 360 minutes under the drying conditions of 60 ℃ and 0.8 kW in the middle infrared emitter. The whole drying stage was mainly slow drying. The Midilli-Kucuk model could effectively predict the moisture change mechanism of macadamia nuts in the middle infrared drying process and the Australian firmness in each period. The effective water diffusion coefficient was between 2.03×10^-7 and 2.31×10^-7 m2/s. The drying activation energy of macadamia nuts was calculated by Arrhenius formula.

Abstract:Beer fermentation is an extremely complicated process, in which the control of fermentation temperature has a great influence on the final taste and quality of the beer. The temperature control of the fermentation liquor has the characteristics of large time delay, nonlinear and staged characteristics, and they cause the temperature of the fermented liquor in the fermentation tank to fluctuate frequently with large. According to the technological characteristics of the beer fermentation temperature control system, a nonlinear PID control strategy was processed based on Smith predictable compensation. After modeling the beer fermentation temperature control system and performing Matlab simulation analysis, it was found that the algorithm could retain the advantages of simple PID parameter adjustment and high steady-state accuracy, as well as the greater anti-interference ability. The system was robust to the parameter perturbations and disturbances. The final production results showed that this control strategy could effectively improve the dynamic quality and anti-jamming ability of the control system and obtain better application achievement.

Abstract:The sensory characteristics, color difference, water holding capacity, texture, K value, total volatile basic nitrogen (TVB-N value), thiobarbituric acid (TBA value) were used as evaluation indexes. The effects of 3 packaging treatments on the quality of cultured Pseudosciaena crocea during 120 d of frozen storage were studied. The results showed that the sensory comprehensive score, texture and water holding capacity of cultured Pseudosciaena crocea decreased gradually with the prolongation of frozen storage time. The TVB-N and TBA values of cultured Pseudosciaena crocea increased with time under three packaging treatments. The results of K value analysis were consistent with those of TVB-N. Compared with the ice-coated group and the unpackaged group, the TVB-N, TBA and K values of cultured Pseudosciaena crocea under vacuum packaging increased slowly. According to the changes of various indicators, vacuum packaging under frozen storage conditions is conducive to maintaining better freshness and frozen storage quality of cultured Pseudosciaena crocea, and the results of this study can provide data support and reference basis for the quality preservation of cultured Pseudosciaena crocea.

Abstract:patterns, color and words are common design languages in packaging design. This paper aims to find out the problems existing in the domestic meat packaging design by referring to the Australian meat packaging design following comparison made between the meat packaging design of China and Australia. And then puts forward the optimization approach to the domestic meat packaging design and theoretical suggestions for the promotion and popularization of domestic meat packaging.

Abstract:A double cam-four-bar combination mechanism was proposed based on the analysis of actuator position and attitude in paper-picking process. By using higher order polynomial and arc combination curve, the contour equation of the main drawing of high-speed paper-picking mechanism with higher order reciprocal continuity and smaller absolute value was obtained. The radius of base circle and the motion angle of cam were analyzed with the aim of pressure angle and angular acceleration of main cam. The results showed that using higher order polynomial and arc combination curve as the main cam contour equation could meet the requirements of the position and attitude of the high-speed paper-picking mechanism actuator. Appropriate radius of base circle and cam motion angle could further reduce the cam pressure angle and angular acceleration.。

Abstract:By evaluating the changes of antioxidant enzyme activity, antioxidant capacity, metabolites, glycogen and lactic acid content in tissues, the effects of different packaging oxygenation modes and transport road conditions on oxidative stress of grouper during waterborne transport were studied. The results showed that the antioxidant enzyme activity, antioxidant capacity and metabolites of grouper under continuous aeration and low oxygen vibration changed non-significantly, which indicated that the body could regulate and maintain the balance of antioxidant system. However, the activities of antioxidant enzymes, antioxidant capacity, lipid metabolites and anaerobic metabolic material production in grouper under very low dissolved oxygen and continuous aeration， and the strong vibration environment changed significantly with the prolongation of transport time. It indicated that very low dissolved oxygen content and the severe vibration could lead to a sharp increase in the content of free radicals in the body, which couldn’t be cleared in time, and the oxidative stress reaction was intense, destroying the balance of antioxidant system. It was concluded that different packaging oxygenation modes needed to be designed to keep the suitable alive rate, according to the distance and conditions of the transportation routing.

Abstract:In order to explore the water diffusion characteristics of kiwifruit during far-infrared radiation drying, low-field nuclear magnetic resonance (LF-NMR) technology was applied to analyze the influence of radiation temperature on internal water states and moisture migration of kiwifruits during drying. The results showed that drying time decreased significantly with the increasing of radiation temperature, and the ratio of average drying rates at radiation temperatures of 120, 160, 200, 240 and 280 ℃ were 1.001.301.542.002.50 respectively. The effective moisture diffusivity values was in the range of 2.85×10^-10~7.03×10^-10 m²/s, which could be improved with the increase in radiation temperature. NMR results showed that the water states in kiwifruits included free water, immobilized water and bound water. With the proceeding of drying process, the relative proportion of free water in kiwifruits decreased gradually, and the removal time of free water reduced by 75% as radiation temperature increased from 120 to 280 ℃. At the early stage of drying, some of the moisture with high degree of freedom moved to the moisture with low degree of freedom. Up to the end of drying, bound water was the main component left in the sample. And higher radiation temperature could accelerate the migration and removal of moisture.

Abstract:To explore the shrinkage influence on fresh shelled peanut hot air drying, improving drying quality, this experiment with fresh shelled peanut as raw material, the selection of different temperature gradient (40, 50, 60 ℃) hot air drying conditions on the shrinkage characteristics were studied, and established the corresponding mathematical model fitting. The results showed that in the drying process, the volume contraction ratio of peanut shell and peanut kernel decreased gradually, the contraction rate increased, and the void volume increased gradually. The peanut shell contracted first than the kernel, and the net structure was seriously deformed after the contraction. Temperature from 40 ℃ to 60 ℃, peanuts and peanut kernel contraction ratio decreased 8.0% and 7.1% respectively. Quadratic model and Vazquez model were the optimal contraction models of peanut shell and nut kernel respectively. The two models had a high degree of fitting and could well reflect the changes of volume contraction during the hot-air drying of fresh peanuts with shell. Therefore, the results of this study can more accurately predict the drying characteristics of fresh shelled peanuts during the hot air drying process, and provide a reference for the optimization of the hot air drying process of fresh shelled peanuts.

Abstract:LED is a kind of green and environment-friendly cold light source, which has the advantages of non-toxicity, non-residue and wide application prospects in killing foodborne pathogenic bacteria in fruit and vegetable postharvest by using LED illumination technology. In this paper, the characteristics, sterilization mechanism and sterilization effect of visible and ultraviolet LED lamps were summarized. The sterilization effect of visible and ultraviolet LED lamps assisted by several different photosensitizers, as well as the dosage, effect and strains of the photosensitizers used werealso introduced. Finally, the existing problems and the future development direction of LED illumination sterilization technology were proposed.

Abstract:To evaluate the food safety of sika deer antler blood freeze-dried powder, the acute toxicity test in mice, and the 30-day feeding and three genotoxicity tests in rats were conducted. The effects of sika deer antler blood freeze-dried powder on alleviating physical fatigue in mice were studied by weight-bearing swimming in the tails, determination of the urea level in serum, the glycogen reserve in liver and the lactic acid level in serum before and after the exercises. Results: the freeze-dried powder of sika deer antler blood was a substance without toxicity according to the acute toxicity test (MTD>15 g/kg·BW). The dosage 0.6, 1.3, and 2.0 g/(kg·BW·d) of freeze-dried powder of sika deer antler blood did not affect the body weight, food intake, blood routine and blood biochemical indexes of rats in 30 days feeding test. The results of three genotoxicity tests were negative. The time of weight-bearing swimming of 0.6 g/kg·BW·d) group was longer than that of the negative control group. The hepatic glycogen reserve of 0.1, 0.2, and 0.6 g/(kg·BW·d) groups was higher than that of the negative control group. The area under the curve of blood lactate change in 0.6 g/(kg·BW·d) group was lower than that in the negative control group. These differences have a statistical significance(P<0.05). Conclusion: The freeze-dried powder of sika deer antler blood was safe to eat and had the function of alleviating physical fatigue.

Abstract:The functional components of anti-myocardial ischemic activity in walnut were studied. The walnuts were squashed and then extracted by 70% ethanol, and ethyl acetate. The ethyl acetate phase was concentrated and then separated by macroporous resin, MCI, and ODS columns. MTT assay and kit method were applied，along with the model of myocardial ischemia/reperfusion injury to detect the anti-ischemic activity of each isolated component. The results showed that 5,10-dihydroxytryptamine and Shepherdine were separated from walnuts for the first time. Moreover, 5,10-dihydroxytryptamine could significantly maintain the viability of myocardial cell and reduce the enzymes (LDH/CK) released by ischemia/reperfusion injury, having significant protective effects on myocardial ischemia/reperfusion injury.

Abstract:Forty male C57BL/6 mice aged 4 weeks were selected and randomly divided into 4 groups. Mice in control groups drank normal water, while those in the experimental groups were treated 1.0% α-ketoglutarate acid (group Ⅰ), or 1.8% leucine (group Ⅱ), or 1.8% leucine and 1.0% α-ketoglutarate acid (group Ⅲ) via drinking water. The experimental lasted 35 days. The results showed as follows: ① The growth performance of group Ⅲ was 8.7%, 10.1%, and 10.4% lower than that of the groups control,ⅠandⅡ, respectively； ② Serum albumin in group Ⅲ was significantly higher than that of the groups control,ⅠandⅡ(P<0.05)； ③ The cardiac index of group Ⅲ increased by 19.3%, 13.6%, and 15.2%, respectively, compared with groups control,ⅠandⅡ； ④ The abdominal fat index of group Ⅲ was 24.1%, 10.0%, and 6.7% lower than that of groups control,ⅠandⅡ, the cross-sectional area of the gastrocnemius muscle of group Ⅲ was 46.9%, 20.2%, 27.9% higher than that of groups control,ⅠandⅡ, respectively. In summary, the combination of leucine and α-ketoglutaric acid can reduce the body weight of mice, strengthen the use of fat by organs, and increase the cross-sectional area of gastrocnemius muscle fibers.

Abstract:The extraction of polyphenols from opuntia milpa was prepared by ultrasound-assisted method. The optimum extraction process was determined by orthogonal experiment with the content of polyphenols and DPPH free radical scavenging rate as indicators. The antioxidant and hypolipidemic activities of polyphenol extract from opuntia milpa were evaluated. The results showed that the optimum extraction technology of opuntia milpa was solid -liquid ratio 115, ethanol concentration 65%, at 65 ℃ for 45 min. Under the control of these conditions, the content of polyphenols was 20.51 μg/mL, and DPPH clearance rate was 87.59%. The polyphenol extract of opuntia milpa has good antioxidant activity. The scavenging ability of hydroxyl radical and superoxide anion reached 93.35% and 59.83% respectively at the concentration of 10 mg/mL. The adsorption capacity of cactus polyphenol extract with cholesterol at pH 2 and 7 was (10.46±0.78) mg/g and (14.65±0.82) mg/g, respectively. At 25 mg/mL, the binding rates with sodium glycocholate and sodium taurocholate were 34.13% and 28.34%, respectively. CONCLUSION: The ultrasonic-assisted extraction process is stable and feasible, and the polyphenol extract has good antioxidant activity and hypolipidemic ability.

Abstract:In different brewing temperature and time, the changes of tea polyphenols and free amino acids brewing from Xiangxi golden tea, which were detected by UV-visible spectrophotometer, was gotten, and the extraction kinetics model was established. The antioxidant properties were also determined by DPPH and ABTS clearance rate. Results, the concentration of tea polyphenols and free amino acids, DPPH and ABTS clearance rate increased with the brewing temperature rising 60~90 ℃, and the brewing time prolonged 1~30 min, and which tended to be stable after 30 min. The Extraction rate of the tea polyphenols and amino acids followed a second-order reaction, and the extraction rate constant k and temperature had a good linear correlation. The apparent activation energy of polyphenols and free amino acids were 4.312 6×10⁴ J/mol and 1.238 9×10⁴ J/mol, respectively.

Abstract:Lactobacillus plantarum, Saccharomyces cerevisiae and acetic acid bacteria screened from previous experiments were taken as the research objects. Selecting two groups of probiotic compound starter L1 (Lactobacillus plantarum and Saccharomyces cerevisiae), L2 (Lactobacillus plantarum, Saccharomyces cerevisiae and Acetobacter) to produce capsicum ferment, and compared with traditional natural fermentation L0. By observing the changes of main quality indexes such as total acid, pH value, alcoholicity and main efficacy enzymes (superoxide dismutase activity, lipase activity) in the fermentation process, Selected the most suitable strain combination for capsicum fermentation. The results showed that the quality of capsicum ferments was significantly improved by mixed fermentation. On the 15th day of fermentation, compared with L0, the total acid content of L1 and L2 increased by 36.53% and 31.42%, lipase activity increased by 99.22% and 96.27%, SOD activity increased by 6.93% and 0.91%, and pH value decreased by 10.35% and 11.05%, respectively. At this time, the sensory score of L1 was （88.75±0.88）, total acid content was 34.82 g/L, alcohol content was 0.023 g/L, pH value was 3.75, SOD activity was 88.71 U/mL, lipase activity was 45.75 U/L, which was significantly better than L2. Therefore, L1, Lactobacillus plantarum and Saccharomyces cerevisiae, were selected as probiotic compound fermentation agents for capsicum enzyme.

Abstract:15 kinds of Japonica and Indica rice, and 4 kinds of glutinous rice flours commonly used in the market for making glutinous rice balls, were selected and compared. The physicochemical properties, sensory characteristics and texture of the commercially available Ningbo glutinous rice balls were investigated. The results showed that the glutinous rice flour made from Zhenuo 106 by water milling was more suitable for the production of Ningbo glutinous rice balls. Its main quality index has reached the quality level of Ningbo glutinous rice balls, and it was the most suitable variety for this processing.

Abstract:Proposed a pixel ratio measurement method, and designs 3 different potato models and 3 different peeling rate orthogonal tests through the model verification method, to verify the determination method. The experimental results showed that there was no significant difference between the actual measured value and the theoretical calculated value of the potato model in the 95% confidence interval, which indicated that the proposed pixel ratio measurement method had a strong credibility in the calculation of the peeling rate of potato. This method is scientific and feasible to evaluate the peeling effect of potatoes, and can be used as an effective method for the quality identification of potato products.

Abstract:The research progresses of fish primary processing machinery at home and abroad were reviewed in this study. Moreover the automatic monitoring technology and its application in aquatic products processing were introduced, from two aspects of material processing quality and the equipment running status. This would help to improve the efficiency and quality of fish primary processing and promote technology upgrading of aquatic processing industry.

Abstract:This review outlined the principle and development of mathematical model based on the theory of heat and mass transfer in porous media. The research emphasis and its progress of mathematical model in the development and application were analyzed from the aspects of evaporation description, parameter determination and definite conditions and so on. Thereafter, an introduction of the advantages and disadvantages of the porous media mathematical model which applied in food thermal processing were given. Moreover, the development prospects of porous media mathematical model applied to fluid-particles food thermal processing were also summarized，which provided a reference for the numerical simulation research of fluid-particles food thermal processing in China.

Abstract:Smoked areca nuts contain harmful substances such as benzo-a-pyrene on its surface, because they are cured in wood smoke in the initial processing process. People's health is seriously threatened by these harmful substances. It is crucial for people to monitor the residues of benzo-a-pyrene effectively in areca nut to ensure the food safety. The sources of benzo-a-pyrene pollution in edible areca nut and the pretreatment methods for detecting benzo-a-pyrene in edible areca nut are summarized in this study, and several instrumental methods for the determination of benzo-a-pyrene in food are also evaluated. Our study is helpful to improving deficiencies and further research.

Abstract:In this paper, the food quick-freezing technology, the shape of ice crystal at different freezing rates and methods for observing ice crystals are described. The research progress of pressure-assisted freezing, electrostatic-assisted freezing and magnetic-assisted freezing in recent years is reviewed. The direct method can directly observe the ice crystal formed during the freezing process. The indirect method analyzes the ice crystal characteristics by observing the gap left by the ice crystal in the food after freezing. Pressure-assisted freezing can improve the super-cooling degree. When the pressure is released, the ice crystals formed by instantaneous freezing are fine and evenly distributed. Electrostatic-assisted freezing reduces the nucleation temperature and promotes the formation of smaller ice crystals. Magnetic-assisted freezing can enhance the hydrogen bond and inhibit the formation of ice crystals. These assisted freezing methods are beneficial to improve the quality of frozen food and have good application prospects.

Abstract:In this review, the research progress of compressor, evaporator and air cooler in trans-critical CO₂ refrigeration system was analyzed. It was concluded that the method of improving the refrigeration efficiency and the optimum heat transfer efficiency of the trans-critical CO₂ refrigeration system was obtained. The application of trans-critical CO₂ refrigeration cycle in CO₂ automotive air conditioning, heat pump and food processing were also discussed. The problems of high system pressure in CO₂ refrigeration cycle in heat pump were analyzed. Finally, it was proposed that the development of oil-free compressor in trans-critical CO₂ refrigeration cycle was one of the main research directions in the future. The application of CO₂ refrigeration system in steaming and freezing of aquatic products, slaughtering of meat and refrigerating transportation of ice cream was prospected.

Abstract:With the development of phase change coolants and insulation technologies, it is expected that the cold storage incubators will be more economical, environmentally friendly, and durable, and have a positive impact on cold chain logistics and peoples lives. Firstly, three types of organic, inorganic, and composite phase-change coolants used in cold storage incubators, as well as new cold storage agents such as microcapsule cold storage agents and nano-coolant developed in recent years were reviewed. Then, from thermal insulation materials and temperature fields, in terms of uniformity, the progress of design optimization of cold storage incubator were expounded, and the feasibility of the new thermal insulation material structure and the influencing factors of the temperature field inside the tank were proposed. The development of efficient and environmentally friendly coolants, optimized insulation structure and temperature field uniformity are the focus of future research on cold storage tanks.