Static and dynamic rheological properties, volatile compounds and sensory characteristics of Antarctic krill (Euphausia superba) pastes fermented at different temperatures (15, 25, and 35 ℃) were investigated. The results showed that krill paste was non-Newtonian pseudoplastic fluid with shear thinning behavior, and had weak gel characteristics. Higher fermentation temperature and longer fermentation time could more significantly break up the gel structure of krill paste, especially at 35 ℃. Fermentation at 25 ℃ improved the stability of krill paste gel. The apparent viscosity, storage modulus and loss modulus of the samples reached maximum levels on the 9th day. A total of 39, 41 and 37 volatile flavor compounds were identified in the three different krill pastes by solid phase microextraction-gas chromatography-mass spectrometry. (E,E)-2,4-Heptadienal, nonanal, decanal, benzaldehyde and benzothiazole were found to significantly contribute to the characteristic odor of krill paste; in krill paste fermented at 25 ℃, 3-ethyl-2,5-dimethyl-pyrazine and 2,3,5-trimethyl-6-ethyl-pyrazine, enhancing its flavor, were also identified, and trimethylamine in krill paste fermented at 35 ℃, responsible for stinky, fishy odor. Krill paste fermented at 25 ℃ for 9 to 12 days showed the best rheological and flavor characteristics.

The gliadin-sugar system was established to simulate the glycosylation modification conditions. The effects of sugar species (monosaccharides, disaccharides and polysaccharides), natural antistatic (dextran) concentration, modification temperature and time, and natural inhibitors on the formation of methyl glyoxal (MGO), glyoxal (GO) and advanced glycation end products (AGEs) were determined by gas chromatography and fluorescence spectroscopy (λex/λem = 340 nm/465 nm). The emulsifying properties of the modified protein were evaluated. The results showed that the amount of various harmful products produced from monosaccharides was much higher than that from polysaccharides, especially a significantly increased amount of MGO compared with GO. Furthermore, the formation of three harmful products increased with increasing dextran concentration, temperature or time prior to reaching a plateau. Under alkaline and high temperature conditions, required for the gliadin-dextran modification system, the common natural inhibitors catechins, quercetin, rutin, genistein, ferulic acid, chlorogenic acid, emodin and capsaicin were unstable, making them less effective. The inhibitory effect of cysteine on MGO and AGEs was more than 70% while still improving the emulsifying properties of the modified protein.

In this paper, the effect of spearmint oil on quorum sensing and spoilage characteristics of Aeromonas sobria was studied. For this purpose, we firstly assessed the inhibitory impact of spearmint oil on the violacein-producing ability of Chromobacterium violaceum 026 (CV026). The signal molecule was detected by gas chromatography-mass spectrometry (GC-MS). The results showed that spearmint oil could reduce the violacein production of CV026 at sub-minimum inhibitory concentrations. When the concentration of spearmint oil was 2 μL/mL, the inhibitory rate of violacein was 56.17%. The secretion of N-acyl-homoserine lactones (AHLs) and some spoilage characteristics such as biofilm formation, extracellular protease activity and bacterial motility of Aeromonas sobria were inhibited by spearmint oil effectively and dose-dependently. These results showed that spearmint oil could be developed as a quorum sensing inhibitor to enhance the shelf life of aquatic products.

This study aimed to research the effect of freezing temperature on beef myofibrillar protein denaturation and water-holding capacity (WHC), and to explore the correlation between myofibrillar protein denaturation and WHC. Beef Longissimus dorsi frozen at ?9, ?18, ?23 and ?38 ℃ were tested. Myofibrillar protein denaturation was investigated by the determination of sulfrydryl content, protein solubility, Ca2+-adenosine triphosphatase (ATPase) activity and protein thermal stability. WHC was evaluated by thawing loss and pressing loss. In addition, muscle water distribution was analyzed by low field nuclear magnetic resonance (LF-NMR) and magnetic resonance imaging (MRI). Color difference and shear force were also measured after thawing at 4 ℃. Results demonstrated that samples frozen at ?23 and ?38 ℃ showed lower degree of protein denaturation, higher protein solubility, Ca2+-ATPase activity and total denaturation enthalpy than those frozen at ?9 and ?18 ℃ (P < 0.05). In addition, L* value, b* value and shear force in thawed samples, thawing loss and pressing loss dropped significantly compared to those frozen at ?9 and ?18 ℃ (P < 0.05). LF-NMR and MRI analyses consistently showed that freezing at ?23 and ?38 ℃ resulted in higher WHC than at ?9 and ?18 ℃. Furthermore, the physicochemical properties (solubility, Ca2＋-ATPase activity, sulfrydryl content and total denaturation enthalpy) as well as L* value, b* value and shear force of beef myofibrillar protein were highly significantly correlated with WHC (P < 0.01). Consequently, myofibrillar protein denaturation during beef freezing had a significant impact on WHC, causing color deterioration, reduced tenderness and juice loss after thaw.

In this study, the structural properties of degerminated corn starch modified by enzymatic extrusion, such as crystallinity and morphological structure, were analyzed by X-ray diffraction, polarizing microscope, scanning electron microscope, hot-stage microscope, differential scanning calorimetry and Fourier transform infrared spectroscopy. The physicochemical properties of native, extruded and enzymatic extruded degerminated corn starch, including enzymatic hydrolysis, iodine blue value, gelatinization degree and amylose content, were studied by using various techniques such as differential scanning calorimetry and Fourier transform infrared spectroscopy. Extrusion and enzymatic extrusion had great influence on starch structure and properties. Enzymatic extrusion could increase the efficiency of enzymatic hydrolysis and the degree of gelatinization degerminated corn, and decrease iodine blue value and amylase content. The morphology and birefringence of enzymatic extruded degeminated corn starch granules was partially destroyed and aggregation of starch granules was observed. The enthalpy change of gelatinization was reduced. The crystal structure of starch granules was destroyed, along with a significant decrease in the degree of crystallinity. The broken starch granules were susceptible to gelatinization and decomposition.

This work was undertaken to establish a model describing the inactivation of Weissella viridescens on lowtemperature smoked ham with ultra-high pressure thermal sterilization (HPTS). Weissella viridescens suspended in phosphate buffered saline and smoked ham inoculated with 108–109 CFU/mL of this strain were subjected to moderate heating (40, 45 and 50 ℃) combined with high pressure (200–500 MPa) held for 5, 10, 15, 20, 25, 30 min. The number of surviving cells was counted by the thin agar layer method. Inactivation curves describing the logarithmic value of the number of inactivated cells as a function of time were fitted with a first-order linear model and the Weibull and Logistic nonlinear models. The goodness of fit of the fitted models was examined by the correlation coefficient (R2), accuracy factor (Af) and mean square error (MSE). It was found that the inactivation of Weissella viridescens in situ was slower than in vitro after HPTS, which was due to the presence of macromolecular substances in the ham matrix including protein and fat, protecting bacteria from damage. Finally, the Logistic equation was the best model to describe bacterial inactivation in vitro and in situ, and could provide the theoretical foundation to predict Weissella viridescens inactivation on smoked hams.

The extrusion and quality properties of four different potato materials including potato, purple potato, sweet potato and purple sweet potato were systematically studied by using a texture analyzer, a rapid viscosity analyzer and a stability analyzer. The results showed that the extrusion properties of potato materials were significantly better than those of sweet potato materials. Potato exhibited the best extrusion properties as reflected by increased expansion degree, gelatinization degree and water solubility index and reduced volume density of extruded potato in contrast to other extruded samples. Correlation analysis showed that the extrusion properties of different potato materials were related to the differences in their major components. The firmness, consistency, trough viscosity, setback and ratio of setback to peak viscosity of potato materials were significantly lower than those of sweet potato materials, indicating that extruded potato had higher cooking degree and better taste. Furthermore, the quality of extruded potato was significantly better that of extruded purple potato (P < 0.05). The results of stability analyzer and stability index showed that the dispersion stability of potato materials especially potato was significantly better than that of sweet potato materials (P < 0.05). Therefore, the extrusion and quality properties of potato materials are superior to those of sweet potatoes and potato is the best of four potato materials.

The total phenols, total flavonoids contents and in vitro antioxidant activities of petroleum ether (PE), ethyl acetate (EE) and n-butanol (BE) soluble fractions from the ethanol extract of sunflower stalk pith were evaluated and correlated with each other. Results showed that EE contained the highest amount of total phenols (1.60 ± 0.10) mg/g calculated as gallic acid equivalent and total flavonoids (20.50 ± 1.55) mg/g calculated as rutin equivalent. EE also had the highest antioxidant activity among three extracts, with half maximal inhibitory concentration of (2.56 ± 0.10) mg/mL, (52.00 ± 1.97) μmol/g and (120.57 ± 0.74) μmol/g for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, 2,2’-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity and total reducing power (the latter two were calculated as Trolox equivalent), respectively. The correlation analysis showed that for all three extracts, there were significant correlations between the contents of total phenols and total flavonoids and DPPH and ABTS radical scavenging activity and ferric reducing antioxidant power (P < 0.01).

The size of ‘Red Globe’ grape bunches is one of the most important quality indicators. A method for size grading of ‘Red Globe’ grape bunches was proposed based on machine vision in this paper. The Red-Green-Blue (RGB) and near infrared (NIR) images of grapes were collected simultaneously with a two-channel camera. Subsequently, the information about green stalks was removed by the normalized super green method from the RGB images, and the local maxima of brightness based on morphological reconstruction was used to identify and locate the grapes in the NIR images. The contours of the fruits were effectively cut and the interference arcs in the edge contour were removed by the gradient segmentation method. Then, the size of the grapes was obtained by random least squares ellipse detection algorithm. A total of 42 bunches of grapes were graded by this method, and 38 of them were graded correctly with an accuracy rate of 90.48%. The accuracy rate is high enough to provide technical support for commercial grape grading.

This study was designed to determine the effect of dietary supplementation with glycerol monolaurate (GML) on the growth perfo4rmance, digestive ability and chicken nutritional compounds of broilers. For this purpose, 1-day-old broilers were fed on a basal diet with or without 150 mg/kg GML for 49 d and the growth performance, intestinal structure, nutrient apparent metabolic rate of broilers and chicken nutritional compounds were measured during this period. The results showed that compared with the control, the GML group could significantly improve feed conversion rate from day 22 to day 49, increased the length of duodenum, jejunum and ileum, villus length in the jejunum and villus height to crypt depth ratio in the duodenum and ileum, and elevate the apparent metabolic rate of crude protein, cuprum and calcium. In addition, dietary GML supplementation significantly increased the relative levels of C18:2 and C20:4, essential fatty acids and polyunsaturated fatty acids in chicken, as well as the contents of crude protein, lysine, aspartate, glutamate, tyrosine, flavor amino acids and total amino acids. In conclusion, dietary GML supplementation could improve the growth performance, digestive ability and meat nutritional compounds of broilers effectively.

The objective of this study was to investigate the effect of different marination methods the quality of braised pork in brown sauce. Injection marination (IM) and variable pressure static marination (VPSM) were employed to prepare marinated meat and no marination was used as control. The rate of marinade absorption of intermediate and final products, product yield, pH, water content, salt content, protein content, fat content, shear force, texture properties, drip loss, centrifugation loss, color, water states and microstructure in different treatment groups were measured. Results showed that the rate of marinade absorption in VPSM was 2.46%, which was significantly higher than that in IM (P < 0.05). The water content of the intermediate and final products, and the product yield in the marinated groups increased significantly compared with the control (P < 0.05). Drip loss and centrifugation loss dropped significantly from raw meat to the intermediates and the final product (P < 0.05) and the lowest values were observed in the VPSM group. VPSM showed better water holding capacity and significantly improved product yield than IM (P < 0.05). As compared to the control, marination significantly reduced fat content and led to a significant increase in protein content followed by a significant drop after cooking (P < 0.05) . The marinated samples had significantly higher brightness (L*) than unmarinated meat; L* value of IM significantly increased, whereas that of VPSM significantly declined after cooking (P < 0.05). Both redness (a*) and yellowness (b*) values of cooked VPSM were the highest compared to raw meat and cooked unmarinated meat, with the differences being statistically significant (P < 0.05). Marination pretreatment significantly reduced shear force and hardness of the final product (P < 0.05), with the effect of VPSM being stronger. The measurement of T2 relaxation time by low field nuclear magnetic resonance showed that marination increased the amount of immobilized water, to a greater degree for VPSM than for IM. As observed by scanning electron microscopy, the microstructure of the muscle fibers in the braised meat was damaged; VPSM showed a more loose structure with the largest gaps between the cooked muscle fibers, contributing to improving the water holding capacity. In conclusion, variable pressure static marination can significantly improve the quality of braised pork in brown sauce and therefore provide theoretical support for improving the existing process.

The longissimus dorsi muscles of Duolang sheep slaughtered at the age of 6 months in factory farming and Gobi desert stocking were used to investigate the differences in slaughter performance, pH, water-holding capacity (WHC), tenderness, color, antioxidant ability, fatty acid content and the ultrastructure of myofibrils. The results showed that the tenderness, lightness after 7 days of maturation and total fatty acids in the factory farming group were better than those in the Gobi desert stocking group (P < 0.05). The WHC, antioxidant ability, redness at day 1 postmortem and polyunsaturated fatty acids in the Gobi desert stocking group were better than those in the factory farming group (P < 0.05). Compared with the Gobi desert stocking group, bigger myofibril density, smaller myofibril diameter and closer myofibril arrangement were observed for the factory farming group. In conclusion, both feeding modes have their own advantages for the meat quality of Duolang sheep and in actual practice, the existing feeding conditions should be improved for producing high-quality mutton.

In order to establish a method for evaluating the taste quality of rice, fuzzy sensory evaluation combined with texture analysis and electronic tongue was used to evaluate the taste quality of cooked rice. The results showed that ‘Dalixiang’ and ‘5H25’ rice cultivars exhibited the best and worst taste based on the fuzzy sensory evaluation and texture analysis, respectively. ‘Dalixiang’, ‘Dalixixiang’ and ‘Jinmazhan’ had similar sensory scores without significant differences in texture (P > 0.05). Electronic tongue gave a good distinction between raw and cooked rice from different varieties by principal component analysis, and the results were consistent with the fuzzy sensory evaluation. A model for evaluating rice taste was established by partial least squares regression analysis, with a correlation coefficient of 0.954 06, which had good performance in predicting the taste of different varieties of rice. Sensory evaluation combined with electronic tongue analysis makes it easy to achieve accurate and reliable evaluation of rice taste quality.

The impacts of four extraction methods (hot water extraction, acid extraction, enzymatic extraction and ultrasonic-assisted extraction) on the yield, structure and antioxidant activities of okra flower polysaccharides were systematically investigated. The results showed that the yield of polysaccharides was in the following decreasing order: enzymatic extraction ((21.90 ± 0.14)%) > acid extraction ((15.15 ± 0.07)%) > hot water extraction ((12.60 ± 0.28)%) > ultrasonic-assistant extraction ((12.02 ± 0.37)%). The polysaccharides extracted by enzyme-assistant extraction and hot water extraction had higher molecular mass and intrinsic viscosity, while ultrasonic-assisted extraction significantly reduced the molecular mass and intrinsic viscosity of polysaccharides and the extracted polysaccharides had a relatively more uniform molecular mass distribution. The polysaccharides obtained by the four extraction methods had identical monosaccharide composition but varied in the molar ratio of monosaccharides, composed mainly of rhamnose, galacturonic acid and galactose. Fourier transform infrared spectroscopy indicated that all four polysaccharides had typical characteristics of polysaccharides. These polysaccharides possessed different antioxidant activities in terms of measurement of 1,1-diphenyl-2-picrylhydrazyl radical scavenging capacity, with the ones extracted by ultrasonic-assisted extraction showing the strongest antioxidant activity．

Objective: The goal of this study was to test the efficacy of cold plasma (CP) for microbial decontamination of blueberries and to investigate the influence of CP on the storage quality of blueberries. Methods: “Brilliant” blueberries were treated with atmospheric CP generated with a 45 kV dielectric barrier discharge (DBD) generator for 50 s. Microbial populations on blueberries, quality indexes and antioxidant enzyme activities were assessed every two days during a storage period of 8 days (20 ℃, 85% RH). Results: Total aerobic mesophilic bacteria and yeast/mold counts were effectively decreased by 1.75 (lg(CFU/g)) and 1.77 (lg(CFU/g)) after cold plasma treatment, respectively. Meanwhile, cold plasma treatment positively affected the quality of blueberries by reducing decay incidence, maintaining fruit firmness and VC content, preventing the increase of titratable acidity at the late stage of storage and increasing the antioxidant enzyme activities. Other qualitative parameters for antioxidant ability were only slightly affected by the treatment. Conclusion: Cold plasma can reduce decay incidence on blueberries. Furthermore, it can induce the antioxidant enzyme activities and improve the storage quality of blueberries.

The aim of this work was to obtain the appropriate pretreatment to improve the drying rate and raisin quality of seedless white grapes in air-drying shelters in Turpan. The experiments were carried out in Turku village in Turpan. The grape samples were divided into control group and three pretreatment groups. Daily data of temperature, humidity, air flow rate, grape moisture content and image were collected during the whole drying process. The eternal quality of grapes such as chromaticity was obtained by image processing using Matlab software. The changes in chromaticity and moisture were plotted against drying time. The results showed that compared with the control group, the drying time of grapes pretreated with 3.0% of drying agent was reduced by 6 days and the surface chromaticity changed more steadily during the drying process. Moreover, the browning rate of raisin was decreased by 67% and the percentage of green raisin was increased by 20.5%. Overall, this pretreatment was found to be optimal for the production of raisin in air-drying shelters. The experiments also validated the use of olive oil to improve the percentage of green raisin during the drying process.

The effects of material thickness, air temperature, air velocity and microwave power on the drying characteristics and effective moisture diffusion coefficient were investigated by using microwave coupled with hot air. Meanwhile, a model for describing the drying kinetics was established through nonlinear fitting. The experimental results showed that the drying process was mainly divided into two periods, namely accelerated and decelerated change of dry basis moisture content, without obvious constant-speed period. The effective moisture diffusion coefficients, ranging from 0.879 1 × 10-6 to 8.245 8 × 10-6 m 2/s, were directly proportional to material thickness, air temperature and microwave power density and initially decreased and then increased with increasing air velocity. Furthermore, the effects of material thickness and microwave power density on effective moisture diffusion coefficient were greater than those of air temperature and air velocity. Among 9 common drying kinetic models, the mean values of R2, χ2 and root-mean-square error for the Two-term exponential model were minimum, which were 0.998 0, 0.000 2 and 0.014 7, respectively. The predicted values from this model were nearly consistent with the experimental values under identical experimental conditions. Therefore, the model could be used to predict the moisture change of Chinese yam during the drying process. These research findings can provide a technical foundation for the application of microwave coupled with hot air in the drying of Chinese yam and other agricultural products.

To investigate the effect of ultrasonic treatment on the quality of goose breast meat, goose breast meat was treated with high-intensity ultrasound at an 800 W power for 42 min (on-time 2 s, off-time 3 s). We examined the effects of ultrasonic treatment and different storage durations (0, 6, 12, 24, 36 and 48 h) at 4 ℃ on goose breast meat tenderness by measuring pH, muscle fibrillation index, cooking loss, shear force, scanning electron microscopy, sodium dodecyl sulfategel electrophoresis of myofibrillar protein and thermodynamics. The results showed that the pH of the ultrasonic treatment group increased, muscle fibrillation index increased significantly, and the cooking loss and shear force significantly reduced when compared with the untreated group (P < 0.05). Moreover, the surface microstructure significantly changed and the heat sensitivity of actin and myosin increased over the untreated group. Additionally, the myofibrillar protein was broken down and actin content was significantly increased with storage time (P < 0.05), thereby significantly improving meat tenderness. Accordingly, ultrasonic treatment could destroy myofibril structure, shorten postmortem aging time, and consequently improve the quality of goose breast meat.

In order to improve the bioavailability of proanthocyanidins, the effect of dynamic high-pressure microfluidization (DHPM) on the average degree of polymerization (DP) and antioxidant capacity of proanthocyanidins was studied. For this purpose, proanthocyanidins were subjected to different DHPM cycles (1, 2, 3 and 4) at different pressure levels (100, 140, 180, 220 and 260 MPa). Results showed that the average DP value of proanthocyanidins was not significantly changed with increasing pressure level, being lower when the processing pressure was 220 MPa. After 4 DHPM cycles, the average DP values were relatively smaller, and the antioxidant capacity (including ferrous ion chelating activity and 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity) of proanthocyanidins treated at different pressure levels followed the decreasing order of 220 MPa > 180 MPa > 140 MPa > 100 MPa > 260 MPa > control group > VC. The opposite was observed for the half maximal inhibitory concentration (IC50) values, indicating that the antioxidant capacity of proanthocyanidins treated at 220 MPa was stronger than that of other samples.

In order to diversify the consumption of millet in the traditional diet, the effect of semidry milling on the quality attributes of millet flour and millet noodles was investigated. The physical and functional properties of millet flour were determined by means of damaged starch analyzer, laser particle size analyzer, X-ray diffractometer, scanning electron microscope and Mixolab. The quality characteristics of millet noodles were determined by low field nuclear magnetic resonance, cooking test, texture analyzer and sensory evaluation. The results indicated that semidry milling of millet at 22% and 26% moisture contents yielded flour with lower percentage of damaged starch and smaller average particle size as compared to dry-milled millet flour (P < 0.05), and consequently semidry-milled millet flour exhibited higher crystallinity degree and superior integrity of starch granules. Moreover, semidry-milled millet flour induced higher water absorption and longer stability time of dough (P < 0.05). Upon gelatinization, the water absorption index and swelling power of semidry-milled millet flour at 26% moisture content were greater than those of dry-milled millet flour during thermal treatment (P > 0.05), showing increased peak viscosity and greater resistance to retrogradation in the Mixolab curves (P < 0.05). Besides, incorporation of semidry-milled millet flour enhanced binding between moisture and other components in millet noodles, leading to an significant increase in the springiness and cohesiveness and a significant reduction in the adhesiveness and cooking loss of millet noodles (P < 0.05). Partial least squares regression analysis indicated that the level of damaged starch granules produced by different milling techniques could have a greater effect on the quality attributes of millet flour and millet noodles as compared to the average size of the starch granules. Due to the lowest degree of starch damage, semidry milling of millet at 26% moisture content can yield high-quality millet flour and millet noodles, which demonstrates a feasible milling method for industrial deep processing of millet.

The physicochemical properties and hydroxyl radical scavenging capacity of coarsely ground powder and superfine ground powders with different grinding times (1, 3, 5, 10, 20 and 30 min) of apple dietary fiber were measured. Besides, particle size measurement and structural observation were performed by laser particle size analyzer and scanning electron microscope. The results showed that after superfine grinding, the particle size of dietary fiber decreased; the swelling power, water solubility and cation exchange capacity significantly increased (P < 0.05), together with a significant increase in the hydroxyl radical scavenging capacity (P < 0.05). There was no significant change in water-holding capacity or bulk density (P > 0.05). The data from this study can provide a theoretical basis for the deep processing and utilization of apple dietary fiber in the food field.

The protective effect of Meretrix meretrix oligopeptide (MMO) on high fat diet-induced kidney injury in mice was examined. A chronic kidney injury model was established by feeding a high fat diet to mice, and then the mice were lavaged with MMO for 30 days. Kidney index was measured, and serum triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) contents were determined as well as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) levels in kidney homogenate. In addition, atherosclerosis index (AI) was calculated and renal pathological changes were examined by hematoxylin-eosin (HE) staining. Immunohistochemical staining was used to detect the protein expression of α-SMA and TGF-β1 in kidney tissue. The results showed that treatment with MMO significantly decreased kidney index, serum TG, TC and LDL-C levels and AI and increased serum HDL-C level as compared to the model group. Treatment with MMO significantly elevated SOD and GSH-Px activities and lowered MDA level in liver homogenate. The immunohistochemical assay showed that MMO markedly down-regulated the protein expression level of α-SMA and TGF-β1 in kidney tissue. Therefore, MMO can effectively protects against chronic kidney injury induced by high fat diet in mice.

In order to evaluate the effect of oral supplementation of four kinds of food-derived bioactive peptides on improving the elasticity of photoaged skin in SD rats and to explore the underlying mechanical mechanism, healthy adult female SD rats were randomly divided into normal control group, ultraviolet (UV) exposure group and four bioactive peptide administration groups. All animals except those in the normal control group were exposed to UVA radiation in combination with UVB. Water solutions of each bioactive peptide were prepared in at concentrations of 0.3, 0.9, and 1.5 g/L for the low, middle and high-dose peptide treatment groups, respectively. The model and peptide treatment groups were exposed to UV irradiation thrice weekly for 18 consecutive weeks until the photoaging model was established. The elasticity of dorsal skin in each animal group was detected with a skin analyzer and then the rats were sacrificed. Approximately 1 g of dorsal skin samples were mixed into 10 mL of buffer solution and homogenized, and then the homogenate was prepared for biochemical measurements. The contents of hydroxyproline and hyaluronic acid (HA) were determined by biochemical assays, and the contents of type I and III collagen, and the activity of matrix metalloproteinase-1 (MMP-1) were determined by enzyme-linked immunosorbent assay. Paraffin-embedded sections of skin tissue were prepared and stained with hematoxylin and eosin for histochemical observation. Results showed that skin elasticity and the contents of collagen I, hydroxyproline and HA in rat skin from the model group were significantly decreased when compared with the normal group, while the content of collagen III and the activity of MMP-1 were significantly increased. Histochemical assays showed epidermal hyperplasia and disorderly arrangement of collagen fibers in the dermis which were broken into fragments aggregated and distorted, together with solubilization and flattening of the basement membrane. In comparison with the model group, skin elasticity in all peptide supplementation groups was improved to some different degrees, with elastinderived peptide showing the best effect, which significantly increased the contents of collagen I, hydroxyproline and HA and significantly decreased the content of collagen III and the activity of MMP-1 (P < 0.05). Histochemical assays demonstrated that elastin-derived peptide markedly improved epidermal hyperplasia, increased the thickness of the dermis and the amount of collagen fibers and restored collagen fibers to the uniform compact wave-like arrangement of the blank control, suggesting that the mechanism of action of elastin-derived peptide was enhancing the biosynthesis of extracellular matrix (ECM) and inhibiting the degradation of ECM by MMP-1 as well as restoring the mechanical structure of photodamaged skin.

Objective: To investigate the intervention effect of ethanolic extract of propolis (EEP) on liver and kidney injury induced by cisplatin (CP). Methods: Rats were treated by intragastric administration with different doses of EEP (50, 100 and 150 mg/kg mb) for 7 days, and then the liver and kidney injury models were established by a single intraperitoneal injection of CP (10 mg/kg mb) at 2 h after the last administration. Finally, the rats were intragastrically administrated for another 5 days. The intervention effect of EEP on cisplatin toxicity was evaluated by measuring the markers of liver and kidney injury in serum and the levels of lipid peroxidation and antioxidants in liver and kidney and observing the pathological changes of liver and kidney. Results: EEP significantly reduced cisplatin-induced toxicity in rat liver and kidney. Compared with the model group, the activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and the contents of blood urea nitrogen (BUN) and creatinine (Cr) in serum were decreased in the high-dose group. The activities of superoxide dismutase (SOD) and catalase (CAT), and the content of reduced glutathione (GSH) in liver and kidney were increased. The contents of malondialdehyde (MDA) and inducible nitric oxide synthase (iNOS) were decreased. The histopathologic examination indicated that the pathological changes of liver and kidney were observed in the model group, with hepatic lobule necrosis and the abscission and cavitation of glomerular cells. These pathological changes were attenuated to varying degrees in the EEP treatment groups. Conclusion: Ethanolic extract of propolis can reduce cisplatin-induced liver and kidney damage by reducing the level of oxidative stress and improving the antioxidant capacity of the body.

Phospholipids are one of the major constituents of cell membranes. Cell membrane stability is affected by phospholipid metabolism, in turn affecting plant growth, senescence and secondary metabolism. The plant resistance inducer benzothiadiazole (BTH) can improve disease resistance in muskmelon (Cucumis melo L.) after harvest, delay fruit senescence, and affect the production of aroma-active secondary metabolites. In the present work, we studied the changes in the contents of phosphatidyl cholines (PC), phosphatidylinositol (PI) and phosphatidic acid (PA) and the activities and gene expression levels of phospholipase A2 (PLA2), phospholipase C (PLC) and phospholipase D (PLD) during the postharvest storage of muskmelon (Cucumis melo L. cv. Yujinxiang), and furthermore, we explored the mechanism of action of BTH in regulating phospholipid metabolism. The results showed that the activity and gene expression of phospholipase in pericarp were inhibited by BTH treatment during postharvest storage, and the activity peaks of PLA2, PLC and PLD in pericarp were reduced by 7.11%, 10.24% and 7.20%, respectively, as compared to the control. BTH treatment augmented the accumulation of PC and PI over the control; the peak values at the end of storage increased by 5.24% and 2.08%, respectively. BTH treatment decreased PA level in comparison to the control and distilled water treatment; PA levels in pericarp and flesh of BTH treated fruits were 20.72% and 8.51% lower than those in the control. BTH treatment inhibited unsaturated fatty acids less than saturated fatty acids. Accordingly, BTH treatment can control postharvest diseases in muskmelon by inhibiting the relative expression levels of PLC and PLD genes and reducing the enzyme activities and therefore decreasing fatty acid production and altering the degree of unsaturation of fatty acids, besides affecting the signal transduction pathways involved in cell membrane metabolism and the generation of secondary metabolites.

The changes of core browning index, mass loss rate, fruit hardness, respiration intensity, ethylene release rate, phenylalanine ammonian-lyase (PAL) activity and PAL gene expression in late-harvested ‘Yali’ pears under slow and rapid cooling conditions were determined in the present study. And the relationship of PAL gene expression with core browning was studied by qRT-PCR as well. The results showed that the browning index of pears with slow cooling was pronouncedly higher than with rapid cooling, and more significant browning was observed with slow cooling. Moreover, slow cooling showed higher PAL activity than rapid cooling as well as higher relative expression level of PAL gene from the 60th day of storage onwards. The relative expression level of PAL gene was significantly positively correlated with PAL activity and core browning index. In conclusion, slow cooling treatment can accelerate core browning, while rapid cooling can inhibit the relative expression of PAL gene, reduce PAL activity, and maintain higher quality of late-harvested pear fruits during storage.

The objective of the present study was to analyze γ-aminobutyric acid (GABA) accumulation associated with postharvest precooling and controlled-atmosphere storage as indicated by GABA metabolism in litchi (Litchi chinensis Sonn. cv. ‘Huaizhi’) fruits. In addition, changes in fruit firmness, color and sensory quality were monitored during storage. The results showed that iced water precooling was better than room precooling for GABA accumulation and storage quality. GABA concentration increased first and then decreased during high-CO2 controlled-atmosphere storage, and the peak concentration (19.97 mmol/kg mf) was 1.4 times as high as that at harvest. There was a positive correlation between GABA concentration and glutamate decarboxylase (GAD) activity, while there was no correlation between GABA concentration and GABA transaminase (GABA-T) activity, indicating that GABA accumulation was mainly due to the enhanced GAD activity, promoting the synthesis of GABA, rather than the decreased GABA-T activity, inhibiting the catabolism of GABA. Pulp firmness, pericarp color and sensory quality of the controlled-atmosphere stored litchi fruits were significantly better than those of the fruits stored under normal atmosphere. Litchi fruits showed serious injury and promptly lost commodity value during excessive CO2 controlled-atmosphere storage.

In order to explore the effect of phlorizin, a phenolic compound uniquely found in apples, on gray mold, the antifungal effect was determined by inoculation of Botrytis cinerea in vitro. The best concentration of phlorizin for in vivo test was screened and used to soak ‘Pink Lady’ apples for 20 min, followed by induction for 12 h, and then B. cinerea was inoculated. The incidence of resistance was measured and resistance-related indexes were determined regularly. Distilled water treatment was used as the control group. The results showed that phloridzin could directly inhibit the growth of B. cinerea in vitro. Phlorizin at 1.0 g/L could significantly reduce the incidence of postharvest gray mold and inhibit the expansion of lesion diameter (P < 0.05). It could also increase the activity of phenylalanine ammonialyase, peroxidase and polyphenol oxidase, and promote the accumulation of total phenols, total flavonoids and lignin. At the same time, it could reduce the content of hydrogen peroxide and increase fruit resistance. These results can provide the theoretical basis for the study on the mechanisms of postharvest diseases in apples.

In order to improve the drying efficiency and the product quality and at the same time reduce energy consumption, alkali (2%, 4% and 6%) pretreatments coupled with heat pump drying (HPD) or hot air drying (HAD) were compared for their application to the drying of Goji berries (Lyciumbar barum). Drying rate, color, rehydration ratio and major nutrients (polysaccharides, carotenoids and flavonoids) were determined. Experimental results showed that the surface wax layer of Goji became gradually thinner and finally ruptured after treatment with sodium carbonate solutions, thereby leading to formation of water channels and consequently reducing drying time. The appropriate sodium carbonate concentration was 2%. In terms of drying efficiency, there was no significant difference between HAD and HPD. However, the Goji dried by HPD showed better color, higher rehydration ratio and higher retention ratio of nutritional components. Compared with drying at constant air temperature and relative humidity, multi-stage drying at varying temperature could not only maintain the quality of dried product, but also was time-saving. The optimum drying conditions of Goji were pretreatment with 2% sodium carbonate solution, and drying at 40 ℃ for 2 h, at 45 ℃ for 4 h, at 50 ℃ for 6 h, and at 55 ℃ for 10 h and at 40% relative humidity. Under these conditions, the drying time was 21 h, and the dried product had a total color difference value of 15.09 and a rehydration ratio of 2.35 g/g, and contained 10.29 g of polysaccharide, 0.43 g of flavonoid per 100 g of sample and 1503.13 μg/g of total carotenoid.

Soybean protein isolate (SPI) as a major ingredient was mixed with glycerol-based biopolyester prepared from modified glycerol to obtain SPI composite films, and changes in the mechanical properties, water content and glycerol migration rate of the resulting films during storage were monitored to investigate the effect of modified glycerol as a plasticizer on the film mechanical stability, water-holding capacity, glycerol migration stability and microstructure. The results showed that the composite films plasticized by a mixture of biopolyglycerol and fatty acid ratio (1:1, m/m) had the highest mechanical stability, and that of the tensile strength, extension at break, water vapor permeability coefficient, water content and glycerol migration rate increased by 18.08%, 34.52%, 14.68%, 17.02% and 74.28%, respectively, compared with the SPI films without unmodified glycerol. Moreover, the structure of the films plasticized by modified glycerol was more compact and continuous, forming a compact network on the surface. In conclusion, the incorporation of glycerol-based biopolyester could improve the mechanical stability of SPI composite films, which will provide the theoretical basis and technical support for broadening the application of SPI composite films.

The purpose of this study was to investigate the effect of Lactobacillus plantarum fermentation broth on the quality of Agaricus bisporus during storage at 4 ℃. The changes in browning, reactive oxygen species content and antioxidant enzymes activities were measured. The results indicated that the fermentation broth maintained the color of Agaricus bisporus, inhibited the accumulation of phenolics and the activity of polyphenol oxidase (PPO), increased phenylalnine ammonialyase (PAL) activity at the late storage stage, reduced H2O2 content, promoted anti-superoxide anion (O2-·) activity, and enhanced peroxidase (POD) and catalase (CAT) activities. Thus, the fermentation broth could keep the storage quality of Agaricus bisporus through preventing enzymatic browning, decreasing the level of reactive oxygen species and enhancing the activity of antioxidant enzymes.

This study focused on the effects of treatments with different concentrations of potassium sorbate (1, 3, 5 and 7 g/L), and/or calcium chloride (5, 10, 15 and 20 g/L) on the resistance to Botrytis cinerea in sweet cherry from the cultivar ‘Qinying 1’. The optimal treatment concentration was screened by measuring the percentage inhibition of mycelial growth, germ tube growth and spore germination of Botrytis cinerea. The results indicated that all treatments could concentration dependently inhibit mycelial growth and germ tube elongation of Botrytis cinerea to different degrees compared with control group and significantly decrease the spore germination rate, and that the best effect was attained by treatments with 20 g/L calcium chloride and 5 g/L potassium sorbate. The inhibitory effect of preharvest spraying with 20 g/L CaCl2 and/or postharvest spraying with 5 g/L potassium sorbate on gray mold incidence, lesion diameter and related enzyme activities in sweet cherry inoculated with Botrytis cinerea during storage for 5 days at (23 ± 1) ℃ was evaluated using sterile water as a control. It turned out that all three treatments effectively inhibited the growth of inoculated Botrytis cinerea and delayed lesion expansion. In addition, both potassium sorbate and CaCl2 could significantly inhibit the content of malondialdehyde (malondialdehyde) and induce the synthesis and accumulation of resistance-associated enzymes (polyphenol oxidase, peroxldase, chitinase, β-1,3-glucanase), increasing the enzyme activities at 1 day or 3 days after inoculation. The combined treatment with 5 g/L potassium sorbate and 20 g/L calcium showed the best inhibitory effect on Botrytis cinerea. The results of this study can provide useful information for reducing the disease caused by invasion of Botrytis cinerea and preserving postharvest sweet cherry.

In order to explore a new method for the preservation of fresh lotus pods, the harvested lotus pods were treated with different concentrations (2.5, 5.0, 10.0, 15.0, and 20.0 mg/L) of 1-(2-chloropyridin-4-yl)-3-phenylurea (CPPU). By analyzing the sensory qualities of lotus pods and seeds, the color difference of lotus seed coats and the protein content of lotus seeds, the optimal concentration of CPPU was selected for the following experiments. Lotus pods without any treatment and those treated with distilled water were used as controls (CK0 and CK1). Then, the effect of CPPU treatment on browning degree, total soluble solids content, starch content, malondialdehyde (MDA) content, hydrogen peroxide (H2O2) content, the rate of superoxide anion radical (O2 -·) generation, super oxide dismutase (SOD) activity, catalase (CAT) activity, peroxidase (POD) activity and polyphenol oxidase (PPO) activity of lotus seeds were investigated during storage at (25 ± 1) ℃. The results showed that the optimal concentration was 5.0 mg/L, and that CPPU treatment effectively prevented the browning of both lotus pods and seeds, maintaining desirable appearance, and inhibited the respiration rate of lotus pods. Moreover, this treatment inhibited the accumulation of soluble solids and starch depletion and lowered the rate of O2 -· generation and the accumulation of H2O2 and MDA. The activities of SOD and CAT were significantly improved, and the activities of POD and PPO were inhibited by CPPU treatment. In addition, the CPPU residue in CPPU-treated lotus seeds was lower than the Chinese national standard limit. Therefore, CPPU treatment is useful for improving postharvest storage quality and delaying senescence of lotus pods and seeds, and will be a promising method for extending the storage life of lotus pods.

Protein is one of the three major nutrients that plays an important role in the food, pharmaceutical and material industries due to its functional properties in addition to high nutritional value. The functional properties of proteins are related to their molecular structure, which can be modified by physical, chemical, enzymatic and genetic engineering methods so as to improve the functional properties, nutritional value and food sensory quality. Therefore, the structural modification of proteins can enlarge their scope of application and meet the industrial demand. Enzymatic modification is a promising method for protein structural modification to obtain modified protein products with defined characteristics because of its high safety, mild reaction conditions, and high product acceptance. This article comprehensively summarizes the recent progresses in the enzymatic modification of proteins, including hydrolysis, crosslinking and covalent grafting. The functional properties of modified proteins are discussed and future prospects for their application are also presented.

In recent years, the applications of bacteriophage in the field of food science have attracted widespread research attention. Due to its own properties bacteriophage can be used as a bactericidal/bacteriostatic agent to control the contamination of foodstuffs by foodborne pathogens and is an ideal tool for food safety. In addition, the development of genetic engineering technology has promoted the efficient and safe applications of bacteriophage and its products, besides the emergence of phage-based products. This review summarizes the recent progress and future prospects of bacteriophage in food safety control.

Color is the most important factor influencing consumers’ willingness to buy fresh meat. In the past forty years, while many researchers have reviewed the factors influencing meat color and its stability, the effects of mitochondria on meat color and its stability have been rarely mentioned in the literature. Mitochondria are very important for myoglobin redox state, and alter meat color and its stability mainly by affecting oxygen consumption and myoglobin reduction. Therefore, the factors influencing mitochondrial structure and function can also affect meat color. This paper reviews the previous research on the association of mitochondria with meat color and its stability. Especially, we summarize the direct mitochondrial effects on meat color and color stability, as well as the factors influencing meat color via mitochondria. Finally, the underlying mechanisms are elucidated.

Emerging evidence suggests that metabolic syndrome, cardiovascular diseases and colorectal cancer are closely associated with the gut microbiota, and the role of these bacteria in the treatment of these diseases has gained considerable research attention, but the pathogenesis and the causal relationship between the gut microbiota and these diseases have not been elucidated to date. The objective of this review is to analyze the changes in structure and species composition as well as metabolic activities of the gut microbiota that can affect the regulation of blood pressure. The association between the gut microbiota and hypertension is discussed in this article. Probiotics are live organisms that are benefit for health and helpful to regulate the balance of the gut ecology. This regulation plays a key role in blood pressure control. In addition, the effect of probiotics on the activity of the gut microbiota is also investigated. Finally, the potential application of gut microbiome as a target in the development of novel therapy for hypertension will be an important research area.

Biogenic amines are a class of organic nitrogenous compounds with low molecular mass and biological activity. Biogenic amines in foods are mainly formed by exogenous microbial enzymes. The appropriate amount of biogenic amines is beneficial to the growth and metabolism of human body, but excessive intake will cause undesirable physiological effects. This paper summarizes the characteristics and hazards of biogenic amines, their formation pathways in foods, the dominant microbial community associated with the formation of biogenic amines in foods, and the key elements controlling the formation of biogenic amines, aiming to provide solutions to control the content of biogenic amines and thus improve the safety of foods.

Polycyclic aromatic hydrocarbons (PAHs) are a class of pollutants hazardous to both the environment and foods. Previously, a lot of research efforts have been devoted to the detection and safety evaluation PAHs in the environment, the detection and control of PAHs contamination in food processing, and the study of the underlying mechanism. This review paper focuses on the chemical mechanism for the formation of PAHs and their formation mechanisms in food processing. Meanwhile, the current studies are briefly reviewed. This review is expected to provide new perspectives on the control of PAHs in food.

In recent years, food adulteration has gradually become an important food safety issue of consumer concern. Driven by interests, adulteration with heterogeneous meat is a particularly serious problem in the meat processing industry. The current technologies available for the detection of heterologous genes in meat products include general polymerase chain reaction (PCR), DNA fingerprinting, real-time quantitative PCR, droplet digital PCR and DNA barcoding. This paper reviews recent progress in the development of technologies for the detection of heterologous genes in meat products, and discusses the advantages and disadvantages of each technology as well as future trend.

The addition of nanocomposites to plastic food packaging materials can yield better mechanical properties and gas barrier performance as well as antibacterial effect. They also, however, have the potential to migrate into foods when coming into contact with them, which may pose health risks to consumers and even has a negative effect on the market and consumer confidence. To evaluate the health risks associated with nanocomposites migrating into foods, it is essential to study the migration behavior of nanocomposites from packaging into foods, which has aroused extensive research interest. This paper reviews the types of plastic nanocomposite food packaging materials as well as the nanocomposites commonly used in food packaging and their roles. A detailed overview of recent studies on the migration behavior of nanocomposites from packaging into foods/food simulants is presented. Although it has been found that only a lesser amount of nanocomposites can migrate from packaging into foods/food simulants, previous studies have not reached a consensus on whether nanocomposites can be released in nanosized form. Furthermore, microwave treatment and plastic additives can affect the migration of nanocomposites.

The antioxidant activity of lactic acid bacteria has been demonstrated in multiple in vivo and in vitro experiments. Lactic acid bacteria play an important role in chelating metal ions, scavenging free radicals, regulating the redox system and regulating the related signal pathways. The development of natural antioxidants and anti-aging agents from lactic acid bacteria is becoming a hot topic in various fields of research. In this paper, we review the current status of studies on the antioxidant activity of lactic acid bacteria with focus on its regulation system, evaluation systems and application in foods. Furthermore, future development trend is discussed.

This paper reviews recent progress in the research on the diversity of lactic acid bacteria in traditional fermented vegetables in China. The predominant lactic acid bacteria in pickled mustard tuber, fermented kohlrabi, northeast sauerkraut, and fermented pepper are analyzed, and problems existing in this field of research are also discussed. It is hoped that this review will provide valuable data for elucidating the role of lactic acid bacteria in flavor formation in traditional fermented vegetables.

Moringa seeds are rich in protein, oil, vitamins, polysaccharides, mineral elements and other nutrients, and possess a variety of pharmacological functions including antioxidant, antibacterial, anticancer, hypoglycemic, hypolipidemic, and hepatoprotective functions. Moringa seeds have been a promising food resource on account of both its culinary and medicinal value. This paper summarizes the major nutritional components of Moringa seeds and systematically reviews recent advances in the pharmacological properties, safety and food application of Moringa seeds. Furthermore, problems existing in this research field are pointed out and some directions for future research priorities and future development trends are presented. We expect that this review will provide useful guidance for scientific application and rational development of Moringa seed-based foods.

Lycopene is one of the most important carotenoids derived from plant foods, which has been evidenced for its antioxidant effect and inhibition against prostate cancer and cardiovascular diseases. In fresh plant foods, lycopene predominantly exists in the all-trans configuration. However, previous studies revealed that all-trans lycopene presents lower bioactivity and bioavailability than its cis-isomers. Thus, in order to upgrade the nutritional quality of lycopene-rich products, it is of much importance to promote the isomerization of lycopene using various food processing technologies such as light, heating, oxidation, pH, and surfactant, of which heating is the most convenient and economical. In the present article, we review the mechanism of thermal isomerization of lycopene and discuss the factors affecting the thermal isomerization of lycopene in model and actual food systems such as solvent type, heating temperature, and heating time. It is concluded that solvent type and the food matrix can exert great influence on the thermal isomerization of lycopene and that increasing the heating temperature and time can facilitate the isomerization or even degradation of lycopene. Finally, problems existing in this field of research and future research directions are proposed.

Heavy metals are one of the principal environmental pollutants. They are hard to transform in the environment and are easy to accumulate through the food chain, thus endangering human health. Heavy metals have been proven to be well absorbed by lactic acid bacteria. This article summarizes the factors influencing the adsorption of heavy metals by lactic acid bacteria (LAB) and the underlying mechanisms as well as the applications of heavy metal absorbing LAB strains in foods. We expect that this review will provide valuable information for further studies on the adsorption of heavy metals by lactic acid bacteria.

Plants from the genus Lilium are used for both medicinal and culinary purposes as a rich source of nutrients. In recent years, they have aroused tremendous research interest in the field of natural product chemistry. However, to date, limited research efforts have been dedicated to the study of Lilium. Only a few Lilium species have been studied. Furthermore, most of the current studies concentrate on the validation of bioactivities, and thus more efforts are needed to study the separation of functional constituents and to develop functional foods and pharmaceuticals from Lilium. This paper summarizes recent progress in the study of nutrients and bioactive components including polysaccharides, saponins, alkaloids, phenols and steroidal glycosides in Lilium as well as its traditional medicinal and culinary applications and bioactive functions. Moreover, future research directions are also proposed.

Lateral flow chromatography is capillary column separation based on antigen-antibody interaction or hybridization between DNA probe and target DNA. Compared with traditional analytical methods, it has the advantages of low cost, short assay time, strong specificity, high stability, non-professional personnel, field test and naked eye visualization. Therefore, it is widely used in clinical medicine, animal and plant medicine, food safety detection, environmental monitoring and other fields. This paper focuses on the background, principle, design, application and prospects of lateral flow chromatography. We hope that this review will provide valuable information for the development of lateral flow chromatography.

The nutritional composition and market value of honey are determined by its floral variety and geographical origin. In order to ensure the nutritional quality of honey, it is extremely important to establish effective methods for the identification of honey traceability. The aim of this article is to review the commonly used methods reported in the literature for honey traceability including identification of pollen and chemical components. Herein we summarize the characteristic markers for honey traceability such as volatile compounds, phenolics, sugar, nitrogen compounds and other trace elements. Hopefully, this review will provide useful information for accurate traceability of honey in the future.