α-Lactalbumin represents one of the major allergens causing cow milk allergy. The identification of the epitopes of α-lactalbumin and the critical amino acids for its allergenicity is of great significance for understanding the mechanism of action of α-lactalbumin and developing hypoallergenic dairy products. In this study, a series of peptides were synthesized by a solid phase method for the characterization of immunological epitopes and critical amino acids. The immunoglobulin (Ig) E-binding epitopes were immunolabeled with individual sera from cow milk-allergic patients as probes by enzyme linked immunosorbent assay (ELISA). Alanine scanning of immunodominant epitopes was used to identify the critical amino acids (aa). The results showed that IgE-binding epitopes were located within the sequences of aa1-15, aa6-20, aa46-60, aa71-85 and aa101-115. Our initial data revealed that Val8, Phe9, Arg10, Tyr103, Leu105 and His107 were the critical amino acids for IgE-binding epitopes. This study will provide the necessary information to alter the cDNA to encode a protein capable of activating milk-specific T cells, but with reduced IgE-binding capacity.

This study compared the effects of five different thawing methods namely water soaking, running water thawing, salt water soaking, air thawing ((10 ± 1) ℃) and refrigeration on the quality of frozen Dosidicus gigas. The results showed that the thawing time with running water was the shortest, followed by salt water thawing. The thawing loss and cooking loss of five thawed samples were significantly different (P < 0.01). Water holding capacity of salt water thawing and refrigeration thawing were higher than those of water soaking thawing and air thawing, which was confirmed by low-field nuclear magnetic resonance (LF-NMR). Carbonyl, sulphur and dimer tyrosine contents of five thawed samples were significantly different (P < 0.01) at ?18, ?4 and 0 ℃. Taking protein oxidation indexes into account, salt water thawing and refrigeration thawing were considered to be the most suitable methods to thaw frozen Dosidicus gigas. Furthermore, there was a certain association between the reduction in water-holding capacity and protein oxidation.

The effect and regulatory mechanism of urea on the properties and non-covalent intermolecular forces of heat-induced myofibrillar protein gel were studied. The relationship between intermolecular forces and gel properties was explored. This study discussed whether urea addition is a scientific method for studying gel hydrogen bonding and hydrophobic interaction. Heat-induced myofibrillar protein gels containing 0.0?0.4 mol/L urea were prepared. The electrostatic interaction was measured using a zeta potential analyzer. The hydrophobic interaction and hydrogen bonding were measured using a Raman spectrometer. The water-holding capacity, hardness and springiness of the gels were measured by a centrifugation method and a texture analyzer. As urea concentration increased, the absolute value of zeta potential of the gels decreased from 7.83 to 5.55 mV, and the surface hydrophobicity (S0-ANS) of myofibrillar protein increased from 698.5 to 885.3. The I760 cm-1/I1 003 cm-1 ratio (normalized intensity) decreased from 0.957 1 to 0.849 3, while the I850 cm-1/I830 cm-1 ratio declined first and then increased. The water-holding capacity, hardness and springiness exhibited a declining trend. Correlation analysis showed that electrostatic interaction, surface hydrophobicity and hydrophobic interaction had a significant effect on water-holding capacity and texture characteristics of heat-induced protein gel.

Soybean protein isolate (SPI) and lecithin can be self-assembled into a complex system at neutral condition (pH 7.0), while the unassembled compounds are still present in the solution. In an effort to achieve maximum complexation between SPI and lecithin and to elucidate the relationship between the functional properties of the complex system and the secondary structure of soybean proteins, we examined the structural variability of the system by Fourier transform infrared spectroscopy and measured its water-holding capacity, oil-holding capacity, gel texture characteristics and functional properties under ultrasound irradiation. The results showed that ultrasonic treatment significantly improved functional properties of the soybean protein-lecithin complex. Water-holding capacity and oil-holding capacity increased firstly then decreased with increasing ultrasonic power after a short irradiation time, but these functional properties continuously decreased with increasing ultrasonic power after a long irradiation time. Fourier transform infrared spectroscopic analysis revealed that the secondary structure of SPI contained a lower content of α-helix and a higher content of β-structure after ultrasonic irradiation at low and medium powers, indicating stronger protein-lecithin interactions. There was a certain relationship between the gel texture characteristics of the complex system and the secondary structure of SPI. The structure of soybean protein-lecithin system could be changed by proper ultrasonic treatment, thus improving its functional properties.

In this study, the effect of pH (5.0–6.5) on flavor characteristics of Maillard reaction products from enzmatic hydrolysates of beef (EBH-MRP) was studied. Results showed that as the pH increased, the sensory properties of EBHMRP were mainly changed from meaty, salty to roast, and bitter flavor. The umami taste intensity of model blank chicken soup was enhanced more weakly, but the kokumi taste intensity was improved steadily. A significant positive correlation was observed between roast aroma and bitterness taste intensity. Excessive roast aroma implied the formation of bitter compounds, which not only could mask the meaty aroma of EBH-MRP but also inhibit its umami, kokumi taste and umamienhancing intensity. Quantitative analysis of flavor compounds demonstrated that meaty aroma intensity was neither correlated with the amount of the important precursor cysteine (Cys), nor with the contents of the key aroma substances. These findings demonstrated that meaty aroma was regulated by the interaction of various odorant compounds, which were generated by an extremely complex mechanism. In addition, a significantly positive correlation existed between the total content of nitrogen-containing heterocyclic odorants and roast aroma intensity. The high molecular weight EBH-MRP (> 3 000 D) was the major contributor to the bitterness taste. The increase of kokumi taste was associated with appropriate degradation of peptides.

The objective of this work was to research the relationship between the conformational changes and allergenicity of tropomyosin (TM) from the white shrimp Litopenaeus vannamei after ultra-high pressure. TM was treated under different conditions of pressure (0.1–800.0 MPa), holding time (10–40 min) and temperature (10–37 ℃) and then tested for changes in it secondary and tertiary structures and allergenicity by circular dichroism spectrum (CD), fluorospectrophotometry and indirect enzyme linked immunosorbent assay (ELISA), respetively. Results showed that both the allergenicity and tertiary structure rather than the secondary structure of TM were changed under different high pressure conditions. There was a significant correlation between the changes in the allergenicity and tertiary structure of TM under different high pressure conditions. In the pressure range tested, the number of surface-exposed hydrophobic amino acids was the lowest at 20 ℃, 40 min, 300 MPa while achieving minimal allergenicity (OD492 nm was 0.210 ± 0.005), and the largest number of exposed hydrophobic amino acids and the maximal allergenicity (OD492 nm was 0.328 ± 0.004) were observed at 700 MPa. Therefore, the allergenicity of TM was related to its tertiary structure but not its secondary structure.

The physicochemical parameters, maturity, textural property analysis (TPA) parameters and dielectric properties of Cheddar cheese with different NaCl contents (0%、1%、2%、3%) during 90-day ripening period were evaluated in an effort to investigate the effect of NaCl addition on the ripening of Cheddar cheese. Results indicated that NaCl addition had a significant impact on physicochemical parameters. Moisture content and water activity descended, while fat content ascended with the addition of NaCl, which was significantly correlated with each of the three parameters. Cheese maturity was promoted more significantly with NaCl addition at low content than at high content. The addition of 1% or 2% NaCl markedly expedited the proteolysis reflecting cheese maturity, which, however, was evidently inhibited with the addition of 3% NaCl. NaCl addition had no impact on the relative dielectric constant. But a significantly positive correlation existed between NaCl addition and dielectric loss factor of Cheddar cheese. NaCl addition had a significant impact on hardness, chewiness and chewiness.

In this study, although both gluten and rice protein could pronouncedly enhance the gel strength and water-holding capacity (WHC), and reduce the cooking loss and transverse relaxation time (T2) of silver carp surimi, gluten was superior to rice protein in improving the gel properties of silver carp surimi. The breaking force, elongation, gel strength and WHC of silver carp surimi gels with 3% gluten were 669.0 g, 12.2 mm, 8 162.0 g·m, and 89.8%, respectively, which were increased by 79.8%, 37.2%, 147.0%, 11.6%, and the cooking loss is 8.51%, which is decreased by 19.7%, respectively compared with the control group. Meanwhile, the transverse relaxation time T23 and T24 were 42.4 and 156.0 ms, respectively. A compact gel network structure was formed with the addition of 3% gluten to silver carp surimi, resulting in an increase in gel strength and WHC. However, the whiteness of the surimi gel declined slightly due to the yellowish color of gluten.

In this study, acid-soluble collagens were extracted from black and white skins of fresh flounder, and their physicochemical characteristics, emulsifying activity and emulsion stability were compared and analyzed. The structural characteristics were studied by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Additionally, solubility, rheological properties, isoelectric point, emulsifying activity index and emulsion stability were also investigated. FTIR analysis proved the existence of amide A, amide B, amide Ⅰ, amide Ⅱ, and amide Ⅲ, confirming that the triple helical chain conformation of the two collagens was completely maintained. The SEM results indicated that both collagens showed a porous, evenly distributed network structure, which proved that the original structure of collagen fibers was basically maintained during the extraction process. The emulsifying activity index (EAI) of the black skin collagen was significantly lower than that of the white skin collagen (P < 0.05), which were (2.60 ± 0.53) and (7.30 ± 0.41) m2/g, respectively, while the emulsion stability index (ESI) of the former was significantly higher than that of the latter (P < 0.05), which were (49.12 ± 5.18) and (27.56 ± 4.91) min, respectively. These results showed that certain differences exist in physicochemical characteristics and functional properties of acid-soluble collagens from different flounder skins.

The pasting properties of Indica rice flours from three different commercial cultivars with different milling degrees were measured using a rapid viscosity analyzer (RVA), and the correlation between pasting properties and milling degree was studied as well. The results showed that for all the cultivars, peak viscocity, minimum viscocity, breakdown and final viscocity increased, whereas pasting temperature declined with the increase in milling time representing milling degree, with the greatest changes being observed for all these parameters from 0 to 30 seconds of milling. The values of peak viscosity, minimum viscosity, breakdown, final viscosity, setback, peak time and pasting temperature were 2 053.00– 3 588.00, 1 006.33–1 801.33, 1 055.67–1 876.67, 2 087.67–2 888.33, 991.67–1 566.33 mPa?s, 5.62–6.09 s, 71.83–75.60 ℃, respectively. It was shown that milling degree was correlated significantly positively with peak viscocity, minimum viscocity, breakdown and final viscocity (P < 0.01), but significantly negatively with pasting temperature (P < 0.01). Therefore, pasting properties are expected to be new physical properties to quantitatively evaluate rice milling degree in practice.

The effect of chrysin on the Maillard reaction between synthetic alliin and fructose was investigated. The results showed that chrysin could slightly increase the production of hydroxymethyl furfural (HMF). It was found that chrysin inhibited the decomposition of alliin with a decomposition percentage of only 10.1% compared with 25.0% for the control. In the earlier stage of the reaction, chrysin facilitated the production of diallyl sulfide, a major volatile sulfur-containing compound. In the later stage, the effect of chrysin on alliin decomposition was minimal leading to 68.2% decomposition of alliin with the production of a mixture of diallyl sulfide, diallyl disulfide, and diallyl trisulfide. HMF greatly promoted the decomposition of alliin, resulting in almost 100% decomposition of alliin after 5 hours of reaction. Therefore, HMF could be deemed as a catalyst for the process.

This study aimed to establish different models to predict some quality parameters (soluble solids, titratable acid and moisture contents) of ‘Lingwuchangzao’ jujube based on dielectric loss factor ?’’ and dielectric constant ?’ spectra and to select the optimal one. The effective information from dielectric spectra was extracted by genetic algorithm (GA) and the correlation coefficient method. The prediction models for quality parameters were established using partial least squares (PLS), principal components regression (PCR) and support vector machine (SVM). The optimal prediction model was determined by the coefficient of determination (R2), root mean square error of calibration set (RMESC) and root mean square error of predication set (RMSEP). The results showed that the optimal prediction models for soluble solids, titratable acid and moisture contents were GA-PCR, GA-PLS and GA-PLS based on dielectric loss factor ?’’ spectra with a R2 value of greater than 0.9, respectively. The best prediction models based on dielectric constant ?’ spectra were CC-PLS, GA-SVM and GA-PLS with a R2 value of greater than 0.8, respectively. These models were validated with satisfactory results. In conclusion, this study can provide a reliable method for rapid prediction of jujube quality using dielectric spectra.

In this research, four kinds of commercially available rice were cooked by four different cooking methods: steaming, high pressure cooking, microwave heating and cooker heating, and a texture analyzer, gas chromatography-mass spectrometry (GC-MS) and sensory evaluation were used to evaluate the physicochemical properties, textural properties, aroma and sensory quality of cooked rice. In addition, the relationship between eating quality and sensory evaluation was discussed. The purpose was to explore the effects of different rice varieties (japonica rice and indica rice), and different cooking techniques on the eating quality of rice, and therefore to offer a theoretical basis for comprehensive evaluation of the eating quality of rice. The results showed that water absorption rate, expansion rate and iodine blue value, adhesiveness and springiness of high pressure cooked rice were larger than those of cooked rice obtained by three other cooking methods, while hardness showed the opposite result. In sensory evaluation, high pressure cooked rice scored highest among the cooking methods, while the eating quality of microwave cooked rice was the worst. There was a significantly positive correlation between rice expansion rate and flavor, shape (P < 0.05, P < 0.01). Hardness was extremely negatively correlated with sensory evaluation scores and taste (P < 0.01). Springiness was extremely significantly positively correlated with rice shape and color (P < 0.01). In addition, the major flavor components (such as aldehydes, ketone, and alcohol) of rice cooked by high pressure and cooker heating were more abundant and diverse than those of other cooking processes, and the species and contents of flavor components in different rice varieties were significantly different.

The thermal degradation kinetics of lycopene and color in red grapefruit was investigated. The results indicated that the degradation of lycopene and color followed the first-order kinetics. The relationship between lycopene content and color during thermal processing at selected temperatures could be expressed by the same equation: C/C0 = 1.770 7 (a*/a0*) + 0.801 2. The relationship between purified lycopene content and color at 70, 80 and 90 ℃ could be described by the following equations: C/C0 = 1.856(a*/a0*) ? 0.841 5, C/C0 = 1.714 (a*/a0*) ? 0.711 8, and C/C0 = 1.492 1 (a*/a0*) ? 0.467 2, respectively. The thermal degradation pathway of lycopene as determined by high performance liquid chromatography coupled with photodiode array detection (HPLC-PAD) included the transformation of all-trans-lycopene into mono-cis-isomer and further into di-cis-isomer during heating, which could be transformed into mono-cis-isomer or degraded, resulting in a decrease in the content of total lycopene.

Peanut is listed among the eight major food allergens by the FAO, and peanut allergy is life-long and could cause hives, vomiting or other symptoms. In the present study, thermal treatment and cysteine reduction were applied individually and in combination on peanut allergen Ara h 2 to study their effect on the allergenic protein. The changes in the structure and antigenicity of Ara h 2 were characterized by circular dichroism (CD) spectroscopy, UV spectroscopy and indirect competitive enzyme linked immunosorbent assay (ELISA), respectively. The results showed that thermal treatment and cysteine reduction could individually change the structure of Ara h 2, leading to a slight decrease in the antigenicity. But the combined treatment resulted in a significant decrease in the antigenicity of Ara h 2 due to the enhanced reducing capacity of cysteine under thermal conditions and consequent remarkable changes in the secondary and tertiary structures of the protein. Moreover, the disulfide bonds played important roles in the structural stability of Ara h 2. When they were destroyed by reduction and heating, the structure and antigenicity changed significantly. These results indicated that reduction combined with heating may be an effective method for eliminating the allergenicity of Ara h 2.

Chronic metabolic diseases, such as type 2 diabetes and obesity, have brought a huge burden to our society. Certain functional foods could bring health benefits to people with metabolic abnormalities, and sometimes help delay the onset of metabolic diseases. Propolis is a traditional Chinese medicine, and has been used as a raw material of functional foods for quite a long time. Pharmacological studies and clinical trials have provided evidence that propolis and its active components could be promising candidates for improving metabolic health. In order to develop standardized functional foods with consistent quality and functions, a systemic view of the mechanism of action is required. We should also be aware that propolis is a combination of multiple active components. Network pharmacology is a recently developed method as an integrative system which enables a systemic investigation of interactions between multiple components and multiple targets. The method of network pharmacology has been used in studies of traditional Chinese medicine. In order to survey the molecular mechanisms of propolis components in treating metabolic diseases, we use structural similarity search to predict therapeutic targets of propolis flavonoids, phenolic acids and esters, and to construct a ‘component-target-disease’ network. Comparing with published data, we calculated that the success ratio of prediction was 86.2%. Based on the network, we concluded that PPARγ, ESR1, ESR2, SITR1 and PTPN1 are key targets of propolis. PPARγ is the most important target for both flavonoids and phenolic acids. Propolis flavonoids and some phenolic acids and esters contribute to the regulation of glucose and lipid metabolism by propolis through various pathways such as lipid metabolism, adipocyte differentiation, insulin secretion and insulin resistance. Based on the results of our study, we introduced a new research tool that can be used in the early stage of functional food development. We found that network pharmacology could provide information for formulating product standards for functional foods, which is important for innovation and upgrading of food industry.

Objective: This study was designed to explore the change in water mobility in skin-on and skin-off pork during blast chilling and spray chilling. Methods: Ten skin-on pork loins were obtained at 2 h postmortem and each loin was cut into 4 steaks (14 cm × 10 cm × 6 cm), the skin of two of which was kept and the other two were skinless. Skin-on and skinless steaks were individually subjected to blast chilling and spray chilling. At 0.0, 1.5, 3.0, 4.5, 6.0 and 7.5 h of chilling, transverse relaxation time (T2) and magnetic resonance images (MRI) were determined by low-field nuclear magnetic resonance (LF-NMR) and sample weight was measured. Results: The A2b and P2b changed without statistical significance (P > 0.05), and the t21, A22 and P22 were significantly decreased during blast chilling (P < 0.05), while spray treatment significantly reduced A22 and P22 (P < 0.05), but it had no significant effect on A2b, P2b, t21, A21 or P21 (P > 0.05). The water mobility in skinless or skin-on pork under two chilling treatments was similar, while the evaporative loss was significantly affected by the treatments (P < 0.05). At the initial stage of blast chilling, the evaporative loss was mainly derived from free water, while it was immobilized water that contributed to the evaporative loss at the late stage. The spray chilling treatment could replace the immobilized water during the removal of heat from pork, resulting in a reduction of evaporative loss.

The effect of micronization of blended flours of five cereals as well as shiitake mushroom powder intended for producing noodles on cooking and texture properties and microstructure was studied. The results showed that the optimal particle size was 160 mesh (0.097 mm) with a volume equivalent diameter of 70.5 μm. The particle size distribution of mixed powders after micronization was mainly in the ranges of 3–40 and 40–500 μm and the optimal cooking time of fivecereal noodles with shiitake mushroom was (13.45 ± 0.26) min. The rehydration rate and water absorption rate of dry matter increased to (93.20 ± 2.28)% and (128.63 ± 2.57)%, respectively, and the dry matter loss rate and breaking rate after cooking reduced to (6.72 ± 0.09)% and (5.00 ± 0.32)%, respectively. Texture profile analysis (TPA) showed that the ductility was (-4.09 ± 0.10) g/s, the hardness and viscosity decreased to (310.39 ± 7.39) g and (-4.87 ± 0.65) g·s respectively, and the chewiness increased to (102.14 ± 3.31) g·s. Tensile test showed that the maximum breaking force of (19.43±0.18) N was obtained at 160 mesh (0.097 mm), along with an elongation of (53.90 ± 0.87) mm. Scanning electron microscopy (SEM) showed that the surface of noodles was greatly improved, the structure became denser and smoother and the porosity was relatively reduced with increasing degree of micronization, thereby being beneficial for improving the cooking endurance and texture characteristics of noodles.

Objective: In this study, we aimed to analyze changes in the physical and sensory properties of Dezhou braised chicken brine during its repeated use for the purpose of providing a theoretical basis for standardized production of Dezhou braised chicken. Methods: Turbiscan stability index (TSI), transparency, particle size, turbidity, viscosity and color parameters of fresh and used braised chicken brine were measured. Results: TSI, transparency, particle size and L* value firstly declined and then tended to be stable, and turbidity, viscosity, a* and b* values increased until reaching a plateau with repeated use of the braised brine. The overall evaluation showed that TSI, transparency, particle size, turbidity, viscosity, and L*, a* and b* values of the brine were 0.5, 0.35%, 25.46 μm, 1 089 NTU, 0.42 × 10-2 Pa·s, 22.63, 0.61 and 6.48, respectively. Furthermore, TSI, transparency, color parameters, particle size and turbidity had significant correlations with each other. Conclusion: The braised chicken brine gradually became a complex and stable multicomponent system during repeated use, achieving the best particle size, turbidity and color parameters, and it was suitable for braised chicken processing and quality standardization.

Cottonseed protein isolate (CPI) was digested in vitro to prepare hydrolysates with antibacterial activity. Ultrafiltration (UF), anion exchange chromatography (AEC), and semi preparative high performance liquid chromatography (semi-P-HPLC) were used to isolate and purify antibacterial peptides from CPI hydrolysates, and the purified peptides were sequenced by electrospray ionization-tandem mass spectrometry (ESI-MS/MS). During the purification process, CPI hydrolysates were separated into three fractions: U-Ⅰ, U-Ⅲ and U-III by UF and the obtained U-Ⅲ, with higher antibacterial ability, was further separated into QF-Ⅰ, QF-Ⅱ and QF-Ⅲ by AEC. After filtration, QF-Ⅱ, which showed higher antibacterial ability, was further fractionated using semi-P-HPLC into four subfractions: PF-Ⅰ, PF-Ⅱ, PF-Ⅲ and PF-Ⅳ, among which, PF-Ⅲ was determined to have the highest antibacterial activity. The purity of PF-Ⅲ showed a single peak in HPLC. Finally, by ESI-MS/MS, and the amino acid sequence of the peptide was identified as ISGLIYEETR (Ile-Ser-Gly-Leu-Ile-Tyr-Glu-Glu-Thr-Arg).

Pigment was extracted from Quercus variabilis acorn shell harvested from Qinba mountain area, China and it was qualitatively analyzed and structurally characterized by ultraviolet-visible (UV-vis) and Fourier transform infrared (FTIR) spectroscopy. Meanwhile, the antioxidant activity was evaluated. The results showed that the pigment contained abundant polyphenols, with condensed tannins being the predominant species, accounting for up to about 89% of the total polyphenols. The UV-vis and FTIR analysis proved that the pigment molecule contained intramolecular hydrogen bonds as well as multiple benzene rings and phenolic hydroxyl groups. The pigment was easily soluble in ethanol, methanol, alkali solution and water, slightly soluble in ethyl acetate, and insoluble in benzene. The pigment exhibited good stability in acidic environments, but its color became darker with increasing pH in alkali environments. The pigment had good resistance to light and heat, and it was stable in K+, Ca2+ and Na+ solution and could basically retain its color although generating a precipitate in Al3+, Mg2+ and Zn2+ solution. The color of the pigment was obviously faded in antioxidant solution but was not changed in reducing agent solution. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging capacity and reducing power of the pigment were stronger than those of VC, while the superoxide anion scavenging capacity was slightly weaker than that of VC. Therefore, the pigment has a good antioxidant effect in vitro．

Protein oxidation will induce changes in functional properties of food proteins and further influence the quality of food. In order to determine the influence of oxidation on functional and heat-induced gel properties of Pampus argenteus muscle protein, we examined the changes in the solubility and emulsifying properties of fish myofibrillar protein (MP) and the water-holding capacity, color and microstructure of heat-induced gels of MP. The results showed that the solubility, emulsifying activity and emulsion stability of MP from P. argenteus were related to the concentration of H2O2 in the model oxidation system. At low concentration of H2O2, all three indicators reached the highest value at 1 h of oxidation, while there was a declining trend with oxidation time at high concentration of H2O2. Water-holding capacity, hardness and springiness of MP gels increased firstly and decreased afterwards, the color parameter L* value rose, and b* value decreased during the oxidation process. At 3 h of oxidation, the microscopic structure of MP gels became more dense and cross-linked at low concentration of H2O2. On the other hand, at high concentration of H2O2, MP particles were gathered into a compact network structure during initial stages of oxidation, which was then completely destroyed at 5 h. Therefore, moderate hydroxyl free radical-induced oxidation of MP from P. argenteus muscle can improve its functional and heat-induced gel properties, but excessive oxidation will cause protein denaturation and aggregation and lower the quality of fish muscle.

In this study, four important factors including pH, co-pigment, sulfur dioxide and microwave influencing the stability of anthocyanins from five blueberry cultivars were investigated. It was found that the color of the blueberry pigments was red at pH less than 4.0, and the stability was stronger at pH 3.0. Five co-pigments including hydroxybenzoic acid, malic acid, citric acid, ferulic acid and tannic acid most significantly contributed to enhancing the color of the pigments, followed by succinic acid, ascorbic acid and sucrose. On the contrary, isoascorbic acid showed a remarkable negative effect on the color of blueberry anthocyanins. Furthermore, succinic acid, sucrose and tannic acid could also enhance the thermal stability of the anthocyanins. Additionally, sulfur dioxide and microwave could damage the stability of blueberry anthocyanins. Taking our results together, the stability of anthocyanins from five blueberry cultivars in this study was in the decreasing order Baldwin, Plolific, Garden Blue, Bright Well and Anna.

Water is widely existed in materials, and it as a polar molecule has a strong response in microwave field. The major components of rice (protein and starch) were chosen to prepare mixtures with different water contents depending on the proportion of rice flour. The effect of microwave treatment conditions and mixing proportion on the generation of free radicals and storage stability of mixtures was investigated. Electron paramagnetic resonance (EPR) was applied to investigate the nature of free radicals in microwaved samples. The free radical content of mixtures with higher water content decreased, which showed that water had a quenching effect on free radicals. Comparison of mixtures of different proportions of rice protein and starch in microwave field showed that rice protein produced more free radicals than starch, and the generation of free radicals from both components had no inhibitory effect on each other. A large number of free radicals were generated in microwaved samples during storage period, and then the EPR signal continued to decline at a slow rate with increasing time of storage.

The antibacterial activity of encapsulated and non-encapsulated eucalyptus essential oil (EEO) was determined by the agar well diffusion method, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were studied by vapor diffusion method. Besides, the chemical composition was analyzed by gas chromatography-mass spectrometry (GC-MS). The results showed that the EEO had antibacterial activity against all tested bacteria, yeast and mold irrespective of encapsulation. Its antimicrobial activity against yeast was the strongest followed by bacteria, and its antimold activity was weaker. The MIC and MBC of EEO did not significantly differ before and after encapsulation, and the major chemical components were identical, including terpenes and alcohols. The disappearance or decrease of some terpenes in the essential oil after encapsulation resulted in a slight decrease in its antibacterial activity; while its MIC remained unchanged, its MBC against Saccharomyces cerevisiae and Penicillium citrinum was slightly increased.

This study aimed to choose a scientific and reasonable drying method to reduce the quality changes and nutritional losses in Rosa roxburghii Tratt. pomace during preservation. The material was dried by three different drying methods: hot air drying, far-infrared drying and vacuum drying, and the drying processes were investigated by mathematical modeling to select the optimal one. The results showed that the Midilli-Kucuk model presented a high correction coefficient (R2), and minimum χ2, SSE and RMSE values, and it could exactly describe and predict all the drying processes above with the highest degree of fitting. In summary, far-infrared drying at 50 ℃ was found to be the best among these drying methods, giving the best quality characteristics, namely, a brightness value L* of 44.12, and a color difference value of 6.87, a water reabsorbing capacity of 7.53, a VC loss rate of 20.54% and a flavone content of 1.97 mg/g.

As an extension of our previous work, where polysaccharides were extracted and purified from the rhizomes and roots of Gentiana scabra Bunge, this study was undertaken to investigate the structure and bioactivity of the polysaccharides. The type of glycosidic linkage was elucidated by methylation analysis. The backbones of the polysaccharides consisted of (→1) terminal and (1→5)-linked arabinofuranosyl, and (1→4)-linked galactopyranosyl residues with small amounts of other residues and branches. The uronic acid contained in the polysaccharides was composed of (1→4)-linked galacturonic acid residues, which played an important role in the bioactivity of the polysaccharides. The polysaccharides could enhance the proliferation of RAW264.7 cells to produce NO due to the increased mRNA expression of NO synthetase. The polysaccharides also could upregulate the mRNA expression of the cytokines COX-2 and TNF-α.

The present study aimed to investigate the effect of fat contents on myofibrillar protein (MP) oxidation, physicochemical characteristics and sensory properties of beef patties during repeated freeze-thaw cycles, and to elucidate the correlation of freeze-thaw treatment and lipid content with protein oxidation. Round beef patties ((100 ± 2) g per piece) with different fat contents were manufactured by adding 0% (F0), 10% (F10), and 20% (F20) beef tallow and the same proportions of salt and other accessory materials to ground beef loin and then stored at -18 ℃ and one-week frozen storage followed by thawing under running water to a core temperature of 0–2 ℃ were carried out five times during the process. The color parameters (a*, b* and L*) and thawing loss rate were determined and MP was extracted from the patties for the measurement of carbonyl content, total sulfhydryl content and protein solubility after each freeze-thaw cycle. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to evaluate MP aggregation and degradation. The results indicated that a* value, total sulfhydryl content and protein solubility decreased significantly, while b* and L* values, thawing loss and carbonyl content increased with increasing number of freeze-thaw cycles and increasing fat addition. SDS-PAGE analysis showed that myosin heavy chains (MHC) were aggregated and paramyosin and actin were degraded with increasing number of freeze-thaw cycles and increasing fat addition. The sensory quality of beef patties increased with the increase in fat content, but decreased with increasing number of freeze-thaw cycles, especially after three freeze-thawing cycles. In addition, harder texture and increased juice loss were observed. Correlation analysis showed that color parameters (L*, a* and b*), thawing loss and protein oxidation indexes (carbonyl content, total sulfhydryl content, protein solubility) were significantly correlated with freeze-thaw cycles and fat content (P < 0.05 or P < 0.01). The results proved that freeze-thaw cycles could induce protein oxidation in beef patties and quality deterioration. Increased fat content enhanced sensory scores, but accelerated protein oxidation and affected physicochemical properties of beef patties. In practice, proper fat content and constant low temperature are necessary for better quality of beef products.

This study investigated the effects of adding different amounts of arabic gum (AG) on the improving the physical stability of oil-in-water (O/W) emulsions prepared with myofibrillar protein (MP). It was demonstrated that the emulsifying activity index and emulsion stability index increased firstly and then decreased with the increase of AG concentrations. Emulsions with 0.3% AG had the highest physical stability and ζ-potential, smallest particle size, and lowest creaming index (P < 0.05). Confocal laser scanning microscopy (CLSM) observation proved that emulsions with 0.3% AG possessed relatively small droplets compared with the ones without AG, which was coincident with the results of droplet size distribution. The micrographs demonstrated that the interfacial membrane in emulsions with 0.3% AG was more compact and stronger than that in the ones without AG. In general, our results revealed that AG promoted the adsorption of protein at the O/W interface and improved physical stability of the MP O/W emulsion.

Objective: The aim of the present study was to investigate the quality characteristics of cooked squid (Dosidicus gigas) and to compare the effects of on-board processing and on-shore processing on the quality and texture of cooked squid. Methods: The microstructure change of squid was observed by using scanning electron microscopy and hematoxylin eosin staining. The changes in the protein composition of squid were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Protein hydrophobicity and the contents of thiol and carbonyl groups were determined to analyze the degree of protein denaturation in squid muscle. The texture of squid was analyzed by a texture analyzer. Then total volatile basic nitrogen and formaldehyde contents, pH and sensory evaluation were determined. Results: SDSPAGE showed that the protein profile of cooked squid slices was basically identical to that of the raw materials. There was no significant difference in hardness or elasticity parameters between both samples (P > 0.05). The myofibrillar structure of on-board processed squid slices was less damaged than that of the on-shore processed ones. The surface hydrophobicity (25.22 μg of bromophenol blue bound), protein denaturation (38.98 nmol/mg pro sulfydryl group content) and degree of oxidization (0.92 nmol/mg pro carbonyl group content) in on-board processed squid slices were significantly lower than those in the on-shore processed ones. Sensory evaluation indicated that on-board cooked squid slices were white, shiny and rich in squid flavor. Furthermore, the squid muscle was solid and flexible, and the overall acceptance score was up to 9.78 points. Conclusion: Cooked slices of on-board processed squid had good quality. The TVB-N content was 29.25 mg/100 g, which can meet the requirements of the national standard GB 2733?2005. The muscle tissue and protein composition of onboard processed squid were rarely damaged, making it suitable for further processing.

In order to explore the effect of Lactobacillus helveticus TS206 on serum lipid levels in mice, health BABL/c mice were divided into two groups. One group was given L. helveticus TS206 bacterial suspension by gavage for 7 consecutive weeks while the other was gavaged with normal saline as control. Body weight, serum lipid levels including total serum cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C), and fecal total bile acid (TBA) levels were investigated in all mice. After the administration of L. helveticus TS206, body weight gains in mice were significantly higher than those in the control group (P < 0.05, P < 0.01), and the mean values of TC, TG and LDL-C were significantly decreased (P < 0.05), which were restored to normal a week after the administration of L. helveticus TS206. There was no significant change in serum HDL-C concentrations between both groups (P > 0.05). Fecal TBA concentration decreased in the intervention group, reaching a value significantly lower than that in the control group after three weeks of administration, while it increased in the control group. This study demonstrated that L. helveticus TS206 could promote body weight gain in healthy mice, and effectively regulate their serum lipid levels, suggesting that orally administered L. helveticus TS206 may reduce the risk of cardiovascular and cerebrovascular diseases.

Objective: To discuss the hypolipidemic, hepatoprotective and laxative effects of dietary fiber from Passiflora edulis fruit peel. Methods: An animal model of hyperlipidemia was established by feeding mice with a high-fat diet in this study, and the mice were gavaged with the dietary fiber modified by the wet method at low, medium and high doses for six weeks. Parameters of interest were measured in the blood and viscera of the mice were measured during the period. Results: The serum levels of total cholesterol (TC), triglyceride (TG), and malondialdehyde (MDA) activity in the positive control group, high dose group, and middle dose group decreased compared with the model group. Moreover, the levels of alanine aminotransferase (ALT), aspertate aminotransferase (AST), high-density lipoprotein (HDL-C), glutathione peroxidase (GSH-Px), and superoxide dismutase (SOD) were improved to some extent. The levels of low-density lipoprotein (LDL-C) in the high dose group and middle dose group were significantly reduced in contrast to the model group. Conclusion: The dietary fiber has good capacity to reduce blood fat and protect liver function in a dose-dependent manner. Although not significant different from each other in terms of the stool quantity, the various dose groups presented a significant increase in the fecal moisture content, indicating that the modified fiber to be effective in preventing constipation.

Objective: To investigate the effect of fermented wheat germ on cholesterol levels in rats with hypercholesterolemia and to elucidate the underlying molecular mechanism. Methods: Male Sprague-Dawley (SD) rats were randomly divided into 8 groups by cholesterol level and body weight. The rats in the control group were fed a normal diet and water, while those in the model were given a high-fat diet and water. The other groups were intragastrically administrated with lyophilized powder of the fermented supernatant at low (LS group, 221 mg/(kg·d)), medium (MS group, 442 mg/(kg·d)) and high (HS group, 884 mg/(kg·d)) doses, and with lyophilized powder of the precipitate at low (LP group, 221mg/(kg·d)), medium (MP group, 442 mg/(kg·d)) and high (HP group, 884 mg/(kg·d)) doses, respectively, all of which were also given a high-fat diet and water. Both the control and model groups received an identical volume of water. The administration lasted for 60 days and at the end of this period, all rats were sacrificed for analysis of serum total cholesterol (TC) and high density lipoprotein cholesterol (HDL-C), liver TC and cholesterol 7α-hydroxylase (CYP7A1), and stool quantity and fecal bile acids (BA). Results: Serum TC level in the rats fed the high-fat diet were significantly increased compared with those fed the normal diet. A rat model of hypercholesterolemia was established successfully. Serum TC levels of the rats in the LS and MP groups were significantly reduced in contrast to those in the model group (P < 0.05 and P < 0.01, respectively). Liver TC concentrations, stool quantity and fecal bile acid levels in all treatment groups were increased, but the differences were not significant statistically compared with the model group (P > 0.05). Conclusion: Fermented wheat germ can time-dependently and dose-dependently reduce serum TC by transferring TC from the serum to the liver, promoting BA formation from TC and increasing stool quantity.

Caco-2 cell model was established and verified to analyze the transport capacity of ACE inhibitory peptides LL and LPEW and to explore their transport mechanism across intestinal epithelial cells. Morphology, transepithelial electrical resistance and alkaline phosphatase activity were measured to verify the validity of the Caco-2 cell model. Apparent permeability coefficient (Papp) of LL and LPEW were (275.17 ± 8.28) × 10-7 and (5.13 ± 1.49) × 10-7cm/s, respectively in Caco-2 transport experiments, suggesting that LL displayed much better intestinal absorption than LPEW. The transportation route of LL may be endocytosis, as demonstrated by comparing the transport capacity of LL with and without transport inhibitors including the paracellular transport accelerator sodium deoxycholate, the endocytosis inhibitor Wortmannin, and the competitive inhibitor of the peptide transports Gly-Pro. LL had no efflux activity, as suggested by comparing the transport capacity with and without efflux inhibitor including the P-glycoprotein inhibitor verapamil, the multidrug resistance protein inhibitor MK-571, and the ATPase inhibitor sodium azide. In conclusion, LL showed good intestinal absorption.

Objective: This experiment was conducted to study the effect of Lactobacillus casei on antioxidant function of HepG2 cells under oxidative stress. Methods: HepG2 cells were randomly divided into 3 groups: control, model (H2O2 induced oxidative stress) and treatment (H2O2 plus Lactobacillus casei) groups. Antioxidant activity in culture supernatants and lysates of HepG2 cells at 12 and 48 h were measured. 4’,6-diamidino-2-phenylindole (DAPI) staining was applied to observe cell morphology in different groups by fluorescence microscopy. Results: Total antioxidant capacity (T-AOC), and glutathione peroxidase (GSH-Px) and catalase (CAT) activities in the culture supernatant, as well as superoxide dismutase (SOD) activity in the cell lysate at 12 h in the treatment group significantly increased by 80%, 30%, 124% and 22%, respectively when compared with their counterparts in the model group (P < 0.05). At 24 h, the activities of T-AOC, SOD, GSH-Px, CAT and peroxidase (POD) were significantly increased (P < 0.05), and the content of glutathione (GSH) and malondialdehyde (MDA) in the culture supernatant in the treatment group significantly decreased by 29% and 63% (P < 0.05); a significant decrease of 20% in SOD activity in the cell lysate was observed for the treatment group compared with the model group (P < 0.05). Moreover, the number of damaged cells was reduced in the treatment group than that in the model group, and most cells in the former group had normal morphology. Conclusion: The addition of Lactobacillus casei could increase antioxidant function of HepG2 cells under oxidative stress.

The chemical antioxidant effect of bile acid salt binding peptide (with molecular weights of 265?1 400 D and peptide content of 75.7%) from fermented sour meat was studied as well as its influence on rat thoracic aorta endothelial cells. The results showed that the antioxidant activity of the bile acid salt binding peptide was enhanced with the increase in its concentration. The IC50 for scavenging hydroxyl, superoxide anion and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals were 2.04, 2.79 and 2.50 mg/mL, respectively, indicating that the peptide had better scavenging effect against hydroxyl radical. Cytotoxicity studies showed that in the concentration range used in this study, the peptide had no obvious toxicity on rat aortic endothelial cells and it could stimulate the release of NO and the secretion of 6-keto-prostaglandin F1α especially at high concentration in comparison with the blank control group. All these results showed that the bile acid salt binding peptide may be beneficial in the prevention of cardiovascular diseases through its antioxidant activity and its effects on vascular endothelial cells.

Changes in physicochemical indicators and bacterial flora of farmed Scophthalmus maximus stored at low (0–10 ℃), ambient and fluctuating temperatures were determined. Meanwhile, the predominant spoilage organisms and shelf life under the three storage conditions were also studied, and shelf-life predictive models were fitted by means of Exponential, School-field and Square-root equations, respectively and their goodness of fit was evaluated. The results showed that the shelf life of farmed Scophthalmus maximus was 6.1–32.6 days at low temperature, and the predominant spoilage bacteria were Shewanella putrefaciens (40.3%) and Pseudomonas spp. (27.4%); the shelf life was 1.3 days at room temperature, and the predominant spoilage bacteria were Aeromonas spp. (47.1%) and Shewanella putrefaciens (29.4%). The temperature characteristic coefficient a, theoretical minimum temperature Tmin and activation energy Ea from the Exponential, Schoolfield and Square-root models were 0.12, –6.6 ℃ and 81.4 kJ/mol, respectively. The goodness of fit of the three models was compared by accuracy factor (Af), bias factor (Bf), root mean square error (RMSE) and mean residual error (MRE), and the predictive ability of the Square-root model was better than that of other models. The model predictions were experimentally validated under isothermal and non-isothermal conditions, and the relative error of the Square-root model was lower than that of the other models, suggesting that it could be used as a reliable to accurately predict the shelf life of farmed Scophthalmus maximus under isothermal and non-isothermal conditions.

The effect of monochromatic light on the oxidation of lipid and myoglobin in raw ready-to-eat tuna was studied for optimizing the lighting condition during display. Tuna akami samples were illuminated by light-emitting diode (LED) lamps with four different monochromatic lights (red, yellow, green and blue) under three different modes, i.e., the same power, the same light intensity, and gradient light intensities. Changes in thiobarbituric acid reactive substances (TBARS) value and methemoglobin content in tuna akami muscle during subsequent storage were measured. The results showed that monochromatic light significantly promoted lipid oxidation and accelerated myoglobin oxidation in tuna samples compared with dark conditions during storage. At the same light intensity, this effect increased with decreasing wavelength, but yellow light was less effective than red light; there was also dependence upon light intensity, especially for blue and green lights in comparison with yellow and red lights. Furthermore, both lipid and myoglobin oxidation followed a zero-order kinetic equation. Therefore, red and yellow lights with long wavelengths rather than green and blue lights with short wavelengths are recommended for raw ready-to-eat tuna products during display.

Objective: To investigate the preservative effect of Ginkgo biloba leaf extract combined with sodium ascorbate (D-VCNa) on fresh-cut Dangshan pear. Methods: Fresh-cut fruit pieces were pretreated with Ginkgo biloba extracts containing 0.25, 0.50, and 0.75 mg/mL flavonoids combined with 1% D-VCNa and then stored at 4 ℃. The changes in quality parameters such as respiration rate, weight loss rate, browning rate, VC content, hardness, peroxidase activity, relative conductivity, soluble solid content and pH during the process were measured to determine the optimal concentration of Ginkgo biloba leaf extract. Results: Pretreatment with each concentration of Ginkgo biloba leaf flavonoids combined with 1% D-VCNa mitigated the increase in respiration rate, weight loss rate and color difference, inhibited the decrease in VC content, hardness and soluble solid content (SSC), delayed the occurrence of browning and the appearance time of peak POD activity, and suppressed the increase in pH and relative conductivity during the subsequent storage. Conclusion: Ginkgo biloba leaf extract with 0.50 mg/mL flavonoids combined with 1% D-VCNa has the best preservative effect on fresh-cut Dangshan pear stored at low temperature, maintaining the storage quality and prolonging the storage life.

Improved Chengkou bacon, a Chinese traditional smoked meat product, was investigated for changes and correlations of quality parameters such as sensory quality, total bacterial count (TBC), acid values (AV), peroxide values (POV) and thiobarbituric acid reactive substances (TBARS) values when stored at 25, 30 or 35 ℃. Shelf life prediction at different storage temperatures was studied as well. The results showed that the sensory quality of smoked bacon during different storage temperatures declined gradually. The TBC, AV, POV and TBARS value rose over storage time and the rate of increase at different storage temperatures was in the decreasing order: 35 ℃ > 30 ℃ > 25 ℃. The first order kinetic equations were calculated according to the Arrhenius curves for peroxide values, which were selected as the key factor for the shelf life prediction model through the Pearson correlation coefficients between sensory score and physicochemical indicators at different storage temperatures. As a result, the predicted shelf life values smoked bacon obtained from the first order kinetic equations were 459, 93 and 24 days at 12、25、37 ℃ at the sensory rejection point, respectively, which were in good agreement with the actual ones.

The effect of antioxidant from bamboo leaves (AOB) combined with different packaging strategies on the preservation of fresh tilapia fillets was evaluated in this study by examining the changes in sensory quality, total aerobic counts, drip loss, pH, total volatile basic nitrogen (TVB-N), and 2-thiobarbituric acid (TBA) during storage. It was shown that AOB had good antimicrobial and antioxidant effects on fresh tilapia fillets. The shelf life of tilapia fillets treated with 0.1 g/100 mL AOB was prolonged by 4–6 days when compared with the control group. Microbial growth was inhibited by AOB combined with vacuum packaging or modified atmosphere packaging, which could reduce the TVB-N and TBA values, decelerate the decrease in the sensory quality and prolong the shelf-life. Freshness indexes under ice storage conditions were significantly better than under cold storage conditions. Compared with the control group, 0.1 g/100 mL AOB treatment combined with vacuum packaging or modified atmosphere packaging could better preserve the quality of fresh tilapia fillets, increasing the shelf life up to 18 days under ice storage conditions. These results suggested that AOB combined with vacuum packaging or modified atmosphere packaging will have a great potential in the preservation of fresh tilapia fillets.

In order to select the appropriate cooking method and the suitable delivery condition for cooked green pepper, nutritional quality and nitrite content of green pepper were measured and analyzed. Green pepper was cooked by four traditional cooking methods including stir-frying, steaming, boiling and microwaving, and then subjected to simulated commercial cold chain distribution at 4 ℃. The contents of nutrients including reductive VC and total phenolics, antioxidant activity (DPPH radical scavenging capacity and FRAP) and nitrite content of green pepper after the cooking and distribution process (cooked peppers were reheated after 0, 1, 4, 8, 12 and 24 h distribution) were investigated. Pulp hardness was selected as an evaluation parameter for consistent cooking degree. Results showed that all four cooking methods could significantly decrease reductive VC content, which showed a true retention value of 76.3%?84.0% after cooking. Cooking could increase total phenolics content and antioxidant activity, and TR levels of total phenolics, DPPH value, and FRAP value were 97.7%?130.6%, 156.76%?203.79%, 156.94%?172.53%, respectively after cooking. Cooking could markedly decrease nitrite content by 6%?18%, which was benefit for human health. Boiling treatment resulted in a 22.06% loss of soluble solids content, while other cooking methods provided good retention of soluble solids. No significant difference was observed among the effects of four cooking methods on reductive VC content. Stir-frying could result in a more significant increase in total phenolic content than the other three cooking methods. Steaming and boiling could lead to a more significant increase in antioxidant activity compared to microwaving and stir-frying, while boiling provided the largest reduction in nitrite content among these cooking methods. In a word, steaming treatment could better keep the nutritional quality of green pepper, and significantly reduce nitrite content. Therefore, in the case of green peppers, steaming treatment was recommended as the most suitable cooking treatment. During 24 h simulated distribution, the nutrient quality of green pepper decreased over time, but nitrite content showed the opposite trend. The rate of change in the nutritional quality of green pepper cooked by steaming and microwaving treatment was relatively low, and so these cooking methods were suitable for green peppers used in the process of simulated distribution. Nutrient contents showed a dramatical decrease during the first 8 h, and nitrite content showed a significant increase after delivered for 24 h. It is concluded that steaming and microwaving are suitable for cuisine with green pepper. The delivery time of cuisine with green pepper should not be more than 24 h and attention should be paid to nutrient preservation within the first eight hours.

The clustered regularly interspaced short palindromic repeat (CRISPR)-associated protein 9 nuclease (Cas9) system has been widely applied in genome editing in microbiology due to its high efficacy, versatility and easy programmability. Herein, we review its applications in the field of food microbiology, especially in food fermentation and pathogenic microbiology. Also, the major factors affecting the genome editing efficacy and future perspectives for the development of this system are discussed. Finally, this review is expected to provide references for research in food microbiology by using CRISPR-Cas9 system.

As increasing research efforts have been made on the nutritional and functional properties of polyphenols and polysaccharides, the interaction between polyphenols and polysaccharides and the underlying mechanism have aroused extensive interest in the food field. This article is aimed to review the non-covalent and covalent interactions between polyphenols and polysaccharides and the underlying mechanisms, the factors affecting these interactions, and their effects on the physicochemical and functional properties of polyphenols. Meanwhile, the prospects for future applications of the interactions in food processing are discussed.

With the further deepening of the free trade area between China and the Association of Southeast Asian Nations (ASEAN), and the complementary enhancement of China-ASEAN agricultural products trade, the volume of agricultural food products trade between the two parties has been rapidly increasing year by year. However, due to the differences in the regulations and standards for agricultural food products in China and ASEAN, there are many existing and potential barriers to bilateral trade. In this article, we summarize the major regulations and standards for agricultural food products in China and ASEAN, and we highlight the similarities and differences between their basic laws and quality and safety standards for agricultural food products. We conclude that these differences have become potential factors restricting China-ASEAN agricultural products trade. Lastly, some countermeasures and suggestions on weakening the trade barriers and promoting China-ASEAN agricultural trade are also proposed.

Fusarium is one of the fungal genera primarily producing mycotoxins. Fusarial toxins, mainly consisting of trichothecene, zearalenone and fumonisin, can cause psychological disorders or even cancers in humans or farmed animals. Their chemical structures and hazards and the molecular mechanisms behind their biosynthesis, together with the application of polymerase chain reaction (PCR) for molecular detection of the mycotoxigenic Fusarium were reviewed in this paper. The significance of rapid molecular diagnosis methodology in early warning and pre-intervention of mycotoxic damage is highlighted. Furthermore, possible problems existing in the present PCR detection systems are presented as well as some strategies to tackle such obstacles and make the systems more reliable.

Heavy metal pollution is one of the hot topics in food safety, which has become a problem of increasing concern. The sources of heavy metal pollutants such as mercury, arsenic, cadmium and lead in foods and their chemical forms and harms to human beings, as well as removal methods are discussed in this article. Meanwhile, we review recent progress in the discovery of lactic acid bacterial species able to remove heavy metals from foods and the underlying mechanism as well as their applications in the food field, which will provide references and guidance for the removal of heavy metals from foods using lactic acid bacteria biosorption.

Carotenoids are lipophilic isoprenoid pigments produced by plants and some photosynthetic microorganisms, which are ubiquitous in nature. Depending on the variety and the bond cleavage positions, carotenoids can be derivatized into various products playing key roles in living organisms such as retinoids, pigments, phytohormones and aroma compounds. Currently, many methods including physical, chemical and biological (specific enzymatic and non-specific enzymatic degradation) methods have been presented to degrade carotenoids. In this article, the classification and functional properties of cleavage products of carotenoids are described. Moreover, this article provides a comprehensive review of the current methods to degrade carotenoids and highlights the advantages of the biological degradation methods with focus on specific enzymatic and non-specific enzymatic degradation as well as the enzymatic cleavage sites. In the end, we conclude with some perspectives on future research efforts to screen highly active carotenoid-degrading enzymes for application in the food industry.

In recent years, the problem of meat adulteration has occurred frequently. Full attention has been paid to DNAbased methodologies for meat species identification because of their high sensitivity and specificity, as well as rapid processing time and low cost. This article presents an overview of the commonly used DNA-based methodologies to verify the authenticity of meat and meat products with focus on their detection limits. Moreover, this review highlights the current applications and future prospects of real-time fluorescence quantitative polymerase chain reaction (PCR) and digital PCR in the identification of animal origin ingredients. Finally, target genes from different sources (nuclear DNA and mitochondrial DNA) are compared in terms of their characteristics and their influence on the sensitivity and specificity of species identification and quantification.