Abstract:The latest information and data of the traffic light signpost labeling system from the official website of British government were collected in this review. Moreover, the origin of the system, the content and format of the labeling, the steps of displaying the nutrition information of the labeling, and the implementation effect of the labeling system were expounded, and then its experience and deficiencies of this system were summarized. Finally, our study will help to enlighten the improvement of Chinese-specific FOP labeling system.

Abstract:Residence time distribution is an important parameter to characterize the flow state of materials during twin screw extrusion, which is closely related to the quality formation of extruded materials. The paper introduced the measurement method of residence time distribution by indicator method and parameters. The impacts of temperature, moisture, screw configuration, die hole, feeding speed and screw speed on residence time distribution in twin-screw extrusion process were analyzed. Due to the complex structure of food ingredients (e.g. starch, protein), researches on determination methods and influencing factors need to be further improved.

Abstract:In this study, polyphenols from Durian hull were extracted by 80% methanol, and their antioxidant and anti-inflammatory activities were investigated based on in vitro antioxidant assays and LPS-stimulated RAW 264.7 cells model. The results demonstrated that durian hull extract was rich in polyphenols, it showed strong antioxidant activity in vitro and it could reduce the expression level of inducible nitricoxide synthase (iNOS) and cyclooxygenase-2 (COX-2), decrease the NO production, and also lower the pro-inflammatory cytokines (TNF-α, IL-1β and IL-6) at the mRNA and protein levels. At the same time, it can inhibit the phosphorylation of IκB and p65 proteins related to the NF-κB signaling pathway and inhibit the expression of NF-κB, thereby reducing inflammatory damages.

Abstract:The effects of different reducing sugars, heat treatment temperatures, and processing methods on the removal of parvalbumin from the crud extrarts were studied by using Maillard reaction.The results showed that the content of parvalbumin in Maillard reaction products (MRPs) was significantly reduced when injecting the xylose solution into the fish at 100 ℃. Moreover, the MRPs had brownish yellow color and sauce flavor. Applying the experimental conditions to the production process of cod dried fish, a cod product with a lower parvalbumin content could be obtained.

Abstract:The proteases such as alkaline protease, neutral protease, papain, bromelain, and complex protease were screened using the degree of hydrolysis (DH) and peptide yield (TCA-YSP) as indicators. The crude oligopeptide of cashew nut was isolated by ultrafiltration, Sephadex-G15, Sephadex-G50 and semi-preparative liquid chromatography. The purity and structure of cashew nut oligopeptide were identified through analytical liquid chromatography and infrared spectra. The results showed that DH and TCA-YSP were (17.06±1.52)% and (26.28±0.13)% respectively, which were significantly higher than those of other proteases. Therefore, alkaline protease was the most suitable protease. The sequence of cashew nut oligopeptide was Ile-Ile-Ala-Pro-Ala-Val-Ala-His (IIAIPAGVAH). The result of antiallergic effect of cashew nut oligopeptide showed cashew oligopeptide at 200 μg/mL significantly inhibited the release of histamine, the expression of β-aminohexose glycinase (β-HEX), and phosphatidylserine eversion in mast cell, indicating that cashew oligopeptide extracted from cashew nut owned outstanding antiallergic effect.

Abstract:In this study, lactic acid bacteria (LAB), Weissella cibaria and Kluyveromyces marxianus were mixed and fermented. The symbiosis of the two strains was studied by measuring strain growth curve. Compared the baking and flavor characteristics between mixed bacteria fermentation (MBF) and single bacteria fermentation of whole wheat bread by analyzing cellulase activity and production of exopolysaccharide (EPS). Results: Compared with the cell counts of single bacteria fermentation [LAB: 9.51 lg (CFU/g), yeast: 8.21 lg (CFU/g)], the cell counts of LAB and yeast in the MBF reached 9.61 and 8.09 lg (CFU/g), respectively, indicating that the two strains had a good symbiotic relationship. Compared with the single LAB fermentation, cellulase activity in the MBF with K. marxianus increased, and the extracellular β-glucosidase activity was 13.59 U/g, increased by 128.40%. After 24 h fermentation, water extractable arabinoxylan (WEAX) content in the sample increased from 0.77 g/100 g to 1.89 g/100 g. In addition, the MBF had the highest EPS content produced of 7.54 g/kg. Compared with whole wheat bread without sourdough, the specific volume and elasticity of the bread containing MBF significantly improved (P＜0.05), as bread crumb hardness decreased. The results of flavor characteristics showed that the flavor intensity of bread containing MBF was significantly higher than that of bread containing samples from single LAB fermentation. In addition, the whole wheat bread had a richer wine and fruity flavor. Sensory evaluation confirmed that whole wheat bread with MBF had the highest overall acceptance compared to other groups.

Abstract:This article reviews the surface structure of LAB and their positive effects derived from their interaction with the gastrointestinal tract. Some lactic acid bacteria (LAB) can colonize the human gastrointestinal tract (GIT) and exert their physiological functions beneficial to the host. Among them, the surface structure of LAB cells can promottheir survival and colonization in the GIT, and many physiological functions are also related to surface structure.

Abstract:Selenium nano particles (SeNPs) were prepared using fish gelatin dispersion system, and its particle size, morphology, and digestive stability were studied by dynamic light scattering (DLS) and scanning electron microscopy (SEM). The antioxidant capacity of SeNPs were determined. The results showed that fish gelatin was excellent dispersion system for preparation of SeNPs. The particle size of SeNPs and its morphology was barely affected by the concentration of fish gelatin dispersion system. Moreover, SeNPs presented good antioxidant ability. Among them, the DPPH radical scavenging ability of SeNPs prepared by 1.000%, 0.500%, 0.125% fish gelatin dispersion system, and IC50 value were 1.846 0, 0.923 0, ＜0.461 5 mg/mL, respectively. Correspondingly, the ABTS radical scavenging ability of SeNPs IC50 value were 0.580 0, 0.387 1, ＜0.193 5 mg/mL, respectively. It was found during the in vitro simulated digestion that gastric digestion would lead to agglomeration of SeNPs, and the agglomerated selenium particles regained nano-size during intestinal digestion.

Abstract:In order to explore the causes of fish tenderness changes during microwave cooking of boiled fish, the physical property analysis method can be used to characterize the maximum shear force of fish meat, and it can also be analyzed from the perspectives of water state, protein denaturation and microstructure by method of measurement like Low field nuclear magnetic resonance(LF -NMR). The results showed that at the first stage of microwave heating (150 s), the connective tissue in fish meat was rapidly broken, and the sarcoplasmic protein was almost denatured completely. Part of the bound water was converted into immobilized water, which gave the fish its unique tenderness. At the second stage of heating period (300 s), fish meat tenderness reaches its maximum and is similar to that of traditional cooking. Excessive heating time (390 s) may result in rupture, contraction, reconnection, and stiffening of fish meat muscle. Therefore, the design of one-step microwave method for cooking fish can shorten the time of microwave treatment, which is conducive to maintaining the combination state of water and the integrity of tissues, so as to ensure the tenderness of fish.

Abstract:The effect of different amount of wheat koji on conventional physical and chemical parameters, organic acid, free amino acid and volatile composition during yellow rice wine fermentation were studied, and experiment of fermentation was compared with enzyme preparations. The result indicated the amount of wheat koji had significant influence on total acid, amino acid nitrogen, organic acid, free amino acid compounds and volatile flavor compounds, with less influences on pH value and reducing sugar content. The contents of amino acid nitrogen, alcohol, organic acid, free amino acid and volatile flavor compounds in the enzyme fermentation samples were found significantly lower than those in the wheat koji fermented samples, and 64.04 g/L of reducing sugar in the sample was not converted. This showed that enzyme preparation could not replace the role of wheat koji in yellow rice wine fermentation, and the flavor of yellow rice wine could be regulated according to the amount of wheat koji added in actual production. Our results chould provide theoretical support for the role of wheat koji in yellow rice wine brewing.

Abstract:The effect of refining on main physical and chemical indexes and volatile components of beef tallow was investigated. The acid value, peroxide value, iodine value, fatty acid composition and aroma composition of beef tallow were analyzed during the refining. The results showed that the acid value decreased first and then increased after the deacidification process, and the peroxide value increased, while the iodine value decreased. Throughout the refining process, the acid value of the beef tallow was 0.37 mg/g with the peroxide value of 0.057 5 g/100 g, and the iodine value of beef tallow was 12.47 g/100 g. There were 16 kinds of fatty acid compositions in beef tallow refining, and fatty acid included oleic acid, palm oil and stearic acid. The Gas-ion migration spectrum analysis results showed that alcohol volatile substances reduced gradually during beef tallow refining process. Aldehydes volatile substances reached its peak in the deacidification process. Aldehydes volatile substances decreased slightly in the beef tallow product, while those esters volatile substances increased gradually during the process of refining.

Abstract:The effects of freeze-thaw processing on the characteristics of hot-air drying and the coefficients of moisture diffusion in Malus domeri (Bois) chev were investigated. The results showed that the freeze-thaw pre-treatments had significant effects on drying characteristics. It was found that freeze-thaw pre-treatments could significantly shorten the drying period and increasing the drying rate. Logarithmic model provided better simulation of drying curves for freeze-thaw M. domeri (Bois) chev. at different drying conditions. The results indicated that Deff increased with the increasing of times of freeze-thaw.

Abstract:In order to reveal the nutritional functions of the fruit bodies and embryo of Dictyophora rubrovolvatas, analyzed the distribution of main components in each part. The results showed that polyphenols (2.43 mg GAE/g), flavones (1.95 mg/g), and vitamin B2 (1.04 μg/g) had the highest contents in the volva of fruit-bodies of Dictyophora rubrovolvata, while the protein and polyphenols had the highest contents in the pileus of fruit-bodies of Dictyophora rubrovolvata, with 27.66 g/100 g and 14.19 g/100 g, respectively. Among three parts of the embryo of Dictyophora rubrovolvata, the polyphenols content of indusium (stip) is the highest (21.47 g/100 g), and the other components were most abundant in the volva。There were complete amino acid species in the various parts of the fruit-bodies and embryo of Dictyophora rubrovolvata, and the total free amino acid contents were 5.13~18.18 mg/g, with the significant difference (P＜0.05). And the glutamic acid content was the highest (1.34~4.86 mg/g). Comparing the nutritional and functional components of the same amount of fresh fruit-bodies and embryo, the contents of polyphenols and vitamin B2 of embryo were 2.06 times and 1.25 times that of fruit-bodies, respectively, and the differences in the other ingredients were small (P＜0.05). Eating embryo of Dictyophora rubrovolvata can achieve the purpose of full nutrient utilization; the nutrient content utilization rate of the edible part of fruit-bodies (pileus, indusium and stip ) was between 49.24%~83.59%, and the nutrient loss rate of the abandoned volva was 16.41%~38.93%. In particular, vitamin B2 was as high as 38.93%, which had a high value-added utilization value.

Abstract:In this study, the biliary tolerance, acid resistance and cholesterol-lowering ability of 11 strains of Lactobacillus were studied, and the mechanism of removing cholesterol from Lactobacillus strains was explored. The cholesterol assimilation results determined by the difference in cholesterol content in the medium indicated that all Lactobacillus strains could assimilate cholesterol at a level of 12.03 to 32.25 μg/mL, and the cholesterol removal ability was related to the growth of the culture. The binding of cholesterol to lactobacilli cells was determined by growth, heat inactivation and dormant cells in phosphate buffer. The dry weight of cholesterol eliminated by heat and dormant cells was 0.79 to 3.82 mg/g; the dry weight of cholesterol cleared by growing cells was 4.53 to 16.03 mg/g. These results indicated that L. casei ASCC 292 and L. acidophilus 4962 strain exhibited good acid and biliary resistance, with the removal of most cholesterol from the medium. Lactobacillus strains could remove cholesterol by various mechanisms, and could be used as a dietary supplement to lower serum cholesterol in the body.

Abstract:The ability of sports drinks for enamel corrosion was measured and evaluated in this study. A single-center-single-blind-random crossover design was performed to balance the residual effects of the 18 test results. The beverages used included beverages containing calcium and maltodextrin (test group), two kinds of sugar-containing sports drink products (containing calcium and positive control) and water (negative control). During the 15-day study period, subjects wore removable human enamel simulation samples and drank 250 mL of beverages 4 times a day. The loss of tooth enamel was measured using contact profilometers on days 5, 10 and 15. On the 15th day, a difference was found between the test groups and the negative control. The positive control gradually eroded, and the degree of enamel corrosion was greater than that of the test group and the negative control, as the treatment lasted longer. The results showed that calcium and pH adjusters might be added to soft drinks, carbonated drinks, and sports drinks, to reduce the long-term corrosion of teeth by drinking drinks.

Abstract:In this study, the experimental condition for qualitative analysis of saccharides in beer was optimized by choosing different matrices, including. 2,5-dihydroxybenzoic acid (2,5-DHB), super DHB, 2,4,6-trihydroxyacetophenone, and setting different beer concentrations from undiluted to 1 000-fold dilution. Results indicated that 2,4,6-trihydroxyacetophenone was better than 2,5-dihydroxybenzoic acid and super DHB in the application of characterizing saccharides in beer by MALDI TOF MS. When the beer sample is diluted 10 times with 2,4,6-trihydroxyacetophenone as matrix, MALDI TOF MS performed well in qualitative analysis of saccharides in beer.

Abstract:To evaluate the uncertainty of the determination of sibutramine content in health foods by liquid chromatography-tandem mass spectrometry. Methods according to BJS 201701 Determination of sibutramine in food,and the content of sibutramine in health foods was detected. According to the approach in measurement uncertainty and results indication(JJF 1059.1 2012), the uncertainty was analyzed, quantified and synthesized. When sibutramine content was 7.04 μg/g,the extended uncertainty was 0.197 μg/g (k=2) under the 95% confidence interval. The main influence factors of the uncertainties in the determination were standard curve fitting process.

Abstract:The purity characterization method for genistein certified reference material was established, and the its uncertainty generated during characterization was evaluated. In this study, we qualitatively analyzed genistein samples by Fourier transform infrared spectroscopy, mass spectrometry, and nuclear magnetic hydrogen spectrometry. Thereafter, two independent methods were used in the purity measurement of certified reference material (CRM) of main components. Moreover, the uniformity, stability and the uncertainty introduced in the whole setting were evaluated. Finally, the purity of the genistein CRM was confirmed to be 99.6%, and the expanded uncertainty was 0.4% (k=2).

Abstract:The ginsenoside in Ciqishen capsule was detected by using HPLC,and the polysaccharide was determined by UV. The safety of Ciqishen capsule were evaluated by the acute toxicity test in rats and mice, with the mutation tests of salmonella test (Ames test),the micronucleus tests of mice bone marrow polychromatic erythrocytes and the experiment of mouse sperm deformity, and the 30-day feeding test was used for toxicological study. The results showed that the average contents of ginsenoside and polysaccharide in Ciqishen capsule were 0.273,3.190 g/100 g. The acute toxicity result showed that the biggest tolerance dose of Ciqishen capsule on rats and mice was more than 24.0 g/kg·BW. The results fell into the scale of non- toxicity, and the three genotoxicity tests were all found negative. The results of test on feeding for 30 days showed that there were no evident influence on the clinic experiment, hematology, biochemistry, the weight and coefficient of visceral organ and several indexes of pathological organization under the experiment dosage range. Our results show that Ciqishen capsule is a safe and non-toxic product with good food safety.

Abstract:When manual testing food and chemical samples, there are problems such as large pretreatment errors and low efficiency. In order to solve those problems, a adding liquid instrument control system for sample pretreatment was designed. The system adopts PLC as the main controller, and the software and hardware of the system were designed according to the control demand analysis of the pretreatment instruments. Combined the characteristics of the S-type acceleration and deceleration algorithm and non-contact liquid addition method. By controlling the acceleration of the deceleration phase during the liquid addition process for the droplet hanging on the tip falling off better, a segmented motor control model suitable for adding liquid was proposed. Finally, the fitting analysis and error compensation were performed on the dosing volume. The experimental results showed that the adding liquid error is within ±0.5%. less than the specified ±1%, whitch satisfies the adding liquid precision requirements of the pretreatment instrument, and has 96 sample positions, which is suitable for pretreatment of large batches of samples.

Abstract:Based on the fuzzy PID control algorithm, combined with the advantages of RBF neural network algorithm, a fuzzy RBFNN-PID control algorithm with logic judgment and self optimization is designed to realize the online optimal tuning of PID parameters. Taking CPU1214C and KP1500 touch screen as the core, the beer fermentation automatic control system and man-machine interface are designed. Matlab simulation and experimental results show that the control algorithm can improve the stability, model mismatch robustness and anti-interference ability of the temperature control system.

Abstract:Red plum apricot was used as the test material, and 0.5 μL/L of 1-MCP drip irrigation fumigation was used in combination with 3 different sustained release rates (1/2 tablets, 1 tablet and 2 tablets were py1, py2, and py3 treatment groups, respectively. ) SO₂ preservative treated red plum apricot and stored at low temperature (0.0±0.8) ℃ low voltage (200 mV) electrostatic field (LVEF). The results showed that all three treatments could effectively improve the postharvest storage quality of red plum apricot and reduce the degree of cold damage. During the entire storage period, the browning index of the py3 treatment group was the smallest, and the browning rate of the control group reached more than 10% after 30 days of storage, while the browning rate of the treatment group was less than 6%, and the hardness of the py2 treatment group was significantly higher than that of the control. The V_C content of the control group and the py2, py3 and py1 treatment group was 1.81, 1.74, and 1.58 times that of the control group, and the sensory and mouthfeel evaluations of py2 treatments, was 2.56 and 2.26 times of the control group, respectively. Among the three treatments, the apricot fruit in the py2 treatment group had the best storage and preservation effect, which was 15 to 25 days longer than the control group. At the same time, the SO₂ residue analysis was performed. Lower than the national food additive limit of Chinese food(≤50 mg/kg) standard.

Abstract:To understand the effects different coated materials on the storage quality of the fresh-cut jackfruit buds, chitosan (CN), same concentrations of cassava starch (CS), chitosan (CN) combined with cassava starch (CS), and chitosan (CN) combined with cassava starch (CS) and cinnamon oil (CO) used as coating were investigated. The results showed that compared with the blank group (CK), the sensory quality of fresh-cut jackfruit could be delayed by the four different kinds of coating treatments under the storage condition of (4±1) ℃ for 18 days. Compared with CN and CS coating group, CN+CS and CN+CS+CO composite coating agents had more significant effects on reducing the color, elasticity, chewability, and inhibiting the content of soluble solids, titratable acid, and microbial growth. After storage for 20 days, the color difference and the total number of bacterial colonies in the CN+CS+CO coating group were 4.46 and 1.1×10⁴ CFU/g lower than those in the CN+CS coating group, and the hardness and titrable acid were 27.1 g and 0.05% higher, respectively. According to the results of all indexes, CN+CS+CO composite coating agent had the best effect on fresh-cut jackfruit.

Abstract:In order to study the quality deterioration of high-quality rice, five kinds of high-quality rice were stored under the conditions of 25 ℃, 50% RH and 37 ℃, 70% RH. The processing quality varies such as germination rate, malondialdehyde, and fatty acid composition. The results showed that during short-term storage, high temperature and humidity inhibited the seed activity of high-quality rice, significantly reduced its germination rate, and increased the MDA content of rice. However, the relative content of fatty acid components in rice grains was relatively stable and less affected by high-temperature and high-humidity conditions during short-term storage. At the same time, compared with indica-japonica hybrid rice, many indicators of japonica rice modified significantly, indicating that its storage quality is more prone to deterioration.

Abstract:In this paper, by establishing and validating a three-dimensional model of heat transfer in multi-layer heat preservation boxes during non-refrigerated food transportation, the key role of radiation heat transfer in packaging boxes is revealed besides conduction. By reducing radiation, the amount of aluminum foil added on the inner surface of food during the first 30 hours of storage was reduced by more than 10%. Putting the initially frozen gel pack in the center of the box can obviously delay its melting and double the storage time of the food. The sensitivity analysis shows that the conductivity of box wall, the emissivity inside the box surface and the emissivity of the gel bag are the key parameters affecting the performance, while the influence of the convection heat transfer coefficient is not very significant.

Abstract:An apple classification algorithm based on wavelet and fuzzy is proposed in order to get the edge of apple image accurately and realize apple automatic classification. Firstly, the apple image is transformed by omnidirectional wavelet, and then processed by fuzzy algorithm. The edge of the apple image is extracted by adaptive threshold, and then the area of the apple image is obtained by using the diffuse filling algorithm. Finally, according to the characteristics of the apple quasi circle, the area is transformed into the straight diameter, and the apple classification is completed according to the diameter. The simulation results show that the accuracy of the algorithm is more than 98% for three grades of apples, which shows that the algorithm can be used in the classification detection of apples.

Abstract:To reveal the changes in microbiota community structure and antioxidant activity of polyphenols from litchi pericarp during culture with human fecal microbiota, litchi pericarp polyphenols were added into the mixed medium of intestinal microbiota solution prepared from fresh feces of healthy volunteers for the anaerobic culture in vitro. The total phenol content and antioxidant activities were measured at 0, 4, 8, 12, 24 and 48 h. The change of intestinal microbiota was analyzed by high-throughput sequencing. The results showed that the total phenol content significantly decreased within 0~48 h and the antioxidant activity was also reduced but did not attain significant level. The value of total phenol content, FRAP and ABTS of 48 h was decreased to 79.06% (P＜0.05), 92.19% and 93.58%, respectively to that of 0 h. The abundance of families, genera and species presented an increasing trend from 0 to 48 h. Among them, the relative abundance of Fusobacterium and Desulfovibrio, as dominant bacteria increased to 13.58 and 10.95 times of that of 0 h, respectively. The relative abundance of Bacteroides and Peptostreptococcus decreased to 57.16% and 20.87%, respectively to that of 0 h. Enterococcus and Phascolarctobacterium showed a synergistic relationship, while Desulfovibrio and Bifidobacterium competed with each other. Our results showed that litchi pericarp polyphenols could change the structure of intestinal microbiota, which might play an important role in the biological activity of litchi pericarp polyphenols.

Abstract:In this study, dried oyster was hydrolyzed by using animal protein hydrolase and flavorzyme to prepare nutritious hydrolysate, which was designed to provide guidance for the high valuable utilization of dried oyster. Firstly, with degree of hydrolysis as the experimental index, the enzymatic hydrolysis single factor and orthogonal optimization experiments were carried out. The results showed that the optimal hydrolysis process combination were the enzymolysis time of 5 h, the ratio of material to liquid of 1∶15 (g/mL), and the total enzyme amount of 3%. Under these conditions, the degree of hydrolysis of dried oyster protein was 33.7%, the protein recovery rate was 78.75%, and the total amount of amino acids in the hydrolysate was 3 662.53 mg/100 mL, of which the essential amino acid content was 38.93%. Secondly, in vitro antioxidant activity of oyster protein hydrolysate was evaluated. The results showed that the DPPH· scavenging capacity of the dried oyster protein hydrolysate was IC₅₀=5.95 mg/mL, and the ABTS free radical scavenging capacity was IC₅₀=10.8 mg/mL. The scavenging ability of hydroxyl radicals was IC₅₀=14.56 mg/mL.

Abstract:The antioxidant activity, hypoglycemic potential, and Alzheimer's therapeutic potential of Cyclobalanopsis glauca Shells were investigated in this study. The hydroxyl radical scavenging ability, DPPH radical scavenging ability, superoxide anion radical scavenging ability, and ABTS radical scavenging ability were used as an indicator for evaluating the in vitro antioxidant activity of Cyclobalanopsis glauca Shells Extract (CGSE). Then the α-glucosidase inhibitory ability of CGSE was evaluated by the fluorimetry assay, and the acetylcholinesterase (AChE) inhibitory ability of CGSE was evaluated by the modified Ellman method. Experimental results showed that CGSE had strong antioxidant activity, their IC₅₀ values of hydroxyl radical scavenging activity, DPPH radical scavenging activity, ABTS radical scavenging activity, and superoxide anion scavenging activity were (273.43±9.55), (8.31±0.08), (26.43±0.14) μg/mL, and (1 662.37±30.71) μg Trolox/g·DW, respectively. The IC₅₀ values toward α-glucosidase of CGSE was (24.81±1.99) μg/mL, which were significantly higher than that of positive control acarbose. CGSE also showed a certain AChE inhibitory ability with the IC₅₀ value of (422.29±25.26) μg/mL.

Abstract:The free radical scavenging ability, metal ion chelation ability and reducing ability of different concentrations of placenta peptide from Tibetan sheep were determined, and the distribution of relative molecular weight, amino acid composition and structural characterization were also investigated to explain the causes of antioxidant capacity. The results showed that the antioxidant capacity of sheep placenta peptide was positively correlated with its concentration, and it had strong radical scavenging ability for DPPH· and ·OH with IC₅₀ of 2.83 mg/mL and 0.94 mg/mL, respectively, which were comparable to BHT. In addition, the placenta peptide from Tibetan sheep also had certain O ·scavenging ability, metal ion chelating ability for Fe²⁺ and reduction ability for Fe³⁺and Cu²⁺. Moreover, the placenta peptide below 1 000 Da of molecular weight accounted for nearly 90% in total peptide, which contained an abundance of aspartic acid, glutamic acid, glycine and so on. Structural characterization results showed that the placenta peptide still remained the proper functional group structures of protein in sheep placental, the micromorphology of dense spherical granular happened, and the rearranged protein molecules aggregated during degradation of proteins to peptide. Based on the results of circular dichroism, the decreased content of α-helices, increased content of β-sheets and random curl were observed. In a word, the placental peptide from the Tibetan sheep have nice antioxidant capacity due to its appropriate content of oligopeptides and amino acids profile, special micromorphology properties and space structure.

Abstract:4 types of lactic acid bacteria (Lactobacillus bulgaricus, L. acidophilus, L. casei, and L. casei) were selected in this study. First, the zinc-rich culture process of lactic acid bacteria was optimized, and then the antioxidant activity of the fermentation supernatant of them was measured, and the digestion stability and bioavailability were further analyzed by in vitro simulated digestion. The results showed that the optimal of zinc addition time for zinc-rich lactic acid bacteria was 10 hours after inoculation, and the zinc ion concentration was 50 μg/mL. The antioxidant activity of lactic acid bacteria supernatant could be improved by zinc-rich culture. Four different types of lactic acid bacteria cultured with oyster polypeptide zinc had higher supernatant free radical scavenging activity than that from other zinc sources. The gastrointestinal release rate of L. bulgaricus cultured with oyster peptide-zinc chelates was (3.46±0.17)%, and the bioavailability was the highest (29.78±0.42) %. In summary, L. bulgaricus was a potential dominant zinc-rich strain. L. bulgaricus cultured with the zinc-rich zinc oyster peptide had good in vitro antioxidant activity, gastrointestinal digestive stability, and bioavailability.

Abstract:In order to explore the effect of adding gardenia fruit, a traditional Chinese medicine with dual function of food and medicine, on the quality of yogurt, ferrmentation characteristics and functional properties were investigated. The effects of GE on the number of live bacteria, acidity, water holding capacity and viscosity of yogurt during fermentation were evaluated, and the antibacterial activity, antioxidant activity, lactic acid bacteria's tolerance to simulated gastrointestinal fluid and volatilization were measured after the fermentation was completed. The results showed that the proper amount of GE could improve the antibacterial and antioxidant activity of yogurt, enhance the tolerance of lactic acid bacteria to simulated gastrointestinal fluid, inhibit the post-acidification of yogurt, and had a certain inhibitory effect on the post-acidification of yogurt. Moreover, the color of GE-added yogurt showed a very beautiful egg yolk color, because GE is rich in natural functional pigments including saffron acid and saffron, with the concentrations of (183.000±5.800) and (108.000±3.500) mg/kg, respectively. Moreover, the composition of volatile flavor substances in yogurt has also been significantly improved by GE adding.

Abstract:The optimum precursor peptides were prepared for Maillard reaction by using enzymatic hydrolysis of wheat gluten proteins. Setting the degree of hydrolysis (DH) and protein dissolution rate as main indexes, the optimum parameters of enzymatic hydrolysis were optimized by partial least squares regression as follows: the concentration of complex protease Ⅰ (2 000 U/g), hydrolyzing with complex protease Ⅰ for 3 h, aminopeptidase concentration (400 U/g), hydrolyzing with aminopeptidase for 2 h, and water/substance ratio (1:12 g/g). The main components of the hydrolysates were small molecule peptides under the above hydrolysis conditions, and the proportion of free amino acids in the enzymatic hydrolysate was 5.59%. The proportion of peptide-bound amino acids in the enzymatic hydrolysate was 94.41%, and the proportion of components with the relative molecular weight smaller than 1 000 was 92.83%. Moreover, the obtained gluten peptides were used to prepare wheat gluten peptides-xylose (WGP-xyl) Maillard reaction intermediates (MRI). Through a two-stage temperature rising process, the optimum preparation conditions of WGP-xyl MRI were determined as follows: the ratio of xylose and peptides was 10%, the pH of the mixture was adjusted to 7.5 and heated at 70 ℃ for 120 min.

Abstract:Fish bone gelatin and fucoidan was used as the wall materials and multilayer fish oil emulsion was prepared by layer by layer self-assembly technology. Multilayer fish oil microcapsules were prepared by spray drying method and the storage stability was studied. According to the changes of Zeta potential, the optimum concentration of wall materials for multilayer emulsion was determined. On the basis of orthogonal experiment, the maximum microencapsulation efficiency of 82.03% was obtained when multi-layer fish oil microcapsules were prepared using the following optimum conditions: ultrasonic time 10 min, ultrasonic temperature 25 ℃, homogenization time 4 min, homogenization rate 5 000 r/min. The results of peroxide value showed that microencapsulation could significantly improve the storage stability of fish oil (P＜0.05), and the oxidation rate of three-layer fish oil microencapsulation was the lowest.

Abstract:Taking the compound fruits and vegetables with Kefir fermented apple pulp-ketchup-sea buckthorn juice, by adding the right amount of inulin, fructooligosaccharides and chlorophyll, a leisure health solid drink was made by freeze-drying in vacuum. With the viable count of Lactobacillus and yeast as indicators, single factor and response surface tests were used to optimize fermentation process. Fermented freeze-dried solid drink were made to different concentration gradients, using unfermented freeze-dried samples as a control, and samples were used to analyze and determine the capacity of hypoglycemic, lipid-lowering and antioxidant in vitro. The results showed that the optimal fermentation conditions were: fermentation time of 46.4 h, inoculum amount of 8.0% and fermentation temperature of 31 ℃. Under these conditions, the viable count of lactobacillus and yeast of the fermented compound fruits and vegetables were 7.58×10¹¹, 7.41×10¹¹ CFU/mL, respectively. The fermented group has higher glucose, lipid-lowering and antioxidant capacity than the control group, and the binding amount of sodium taurocholate (lipid-lowering capacity) and hydroxyl radical scavenging rate (antioxidant capacity) of fermented group is significantly higher than that of the control group (P＜0.01).

Abstract:The effects of oral rehydration solutions (ORS) and sports drink solutions (SDS) on the hydration and metabolism of experimental rats during high temperature exercise were compared. The results showed that the hemoglobin level of the two groups increased significantly, and the sweating rate and dehydration rate had no significant difference. In the two treated groups, the change of plasma volume was significant difference, and the blood glucose content was significantly higher than that of the control group. After exercise, the fat oxidation in SDS was lower than that in ors. However, no difference was found between groups of ORS and SDS in the capacity of body fluid retention when water was replenished during the high temperature exercise. This indicated that the amount of fluid ingested during exercise in hot environment might be more important than the content of beverage. Sports drinks could maintain better blood glucose level. In the case of limited CHO intake during the long-time and high-intensity work, such as in continuous exercise or outdoor work, sports drink intake was a better choice. The results of the study will provide reasonable suggestions for the safety work and physical performance of athletes, military personnel and outdoor high-intensity workers.

Abstract:The effects of color protection to candied apple under different processing parameters were studied by using Shangdong red Fuji as raw material. Sensory evaluation and brightness (L value) and browning degree were used as evaluation indexes, and the effects of slice thickness, phytic acid concentration, microwave blanching power, microwave blanching time, hot air drying temperature and drying time on the color protection effect of candied apple were analyzed by single factor experiment. Moreover, the storage of phytic acid and other color-protecting agents were compared in order to obtain the best conditions for candied apple color protection. The results showed that the optimum conditions for apple color protection were slice thickness 8 mm, phytic acid concentration 0.12%, with microwave blanching power at medium-high fire for 80 s, and then drying at 70 ℃ for 4 h. The effect of different color-protecting agents during storage ranges from good to bad: phytic acid＞ascorbic acid＞citric acid＞NaCl, the best color-protecting agent is phytic acid. The candied apples harvested under the control of these conditions showed best color protection with good taste.

Abstract:In this study, using the deuterium dilution technique, the hydration abilities of three kinds of sports drinks commercially available and drinking water (control group) under rest and exercise conditions were compared. The results showed that significant differences were found, in the rest state, including the time points as the absorption rate of the three beverages reached the maximum value, 50% of the maximum absorption rate, and the maximum absorption amount. However, no significant difference was found in the time when the absorption rate was 0. In the exercise status, a significant difference between the time when the absorption rate of drinking water and sports drinks reaches the maximum was also found. The results showed that the deuterium tracer labeling method could effectively measure the relative rate of ingested liquid being absorbed by the organism, and the replenishment capacity of the three kinds of commercial sports drinks was not significantly different from that of drinking water.

Abstract:Based on the materials of upper, middle and lower tobacco leaves planted in Yunnan and Henan Province, the changes in physical indexes, chemical components, and sensory quality under the conditions of 150~190 ℃ airflow temperatures of pneumatic drying were studied. The results showed that: ① at the higher airflow temperature, the Yunnan tobacco had better processing resistance and crush resistance; ② different airflow temperatures changed the flavor, the quality of aroma, mixed gas, irritancy, dryness and cleanness of the taste. The quality of aroma, mixed gas and delicate degree generally improved during 150~160 ℃ airflow temperature range, but the airflow temperature higher than 180 ℃ had negative effect on the taste; ③ the grey correlation analysis of chemical components and sensory quality showed that total sugar, total nitrogen and reducing sugar had a greater correlation with sensory quality.

Abstract:In this study, the main detection methods based on specific molecular recognition of biological probes in recent years are reviewed, including enzyme-linked immunosorbent assay, lateral flow immunoassay and electrochemical biosensor. The advantages and disadvantages of each method are analyzed.

Abstract:This main components and functions of various types of fruit wines were analyzed. The clarification of the nutritional components was elaborated, which helped to find the nutritional and healthy selling points of fruit wine and its precision marketing concepts. This would strengthen the brand building of Chinese fruit wine enterprises in the future.

Abstract:Based on molecular structure and physical and chemical properties, we compare the characteristics of melanin separation and purification by different methods, and summarizes the antioxidation, immunomodulation, radiation protection, antiviral, chelated metal ions, antitumor, organ protection, anti-inflammatory and antibacterial properties of melanin. Biological activities, such as DNA protection, focus on the characteristics and mechanisms of antioxidant, metal chelation, anti-tumor, and radiation protection, and provide guidance for the higher value utilization of melanin.