內容: Available evidence suggests that the consumption of edible insects may not only contribute protein and other valuable nutrients to the human diet but may also provide health benefits through various insect-derived peptides and bioactive compounds. Most studies of potential anti-obesity effects of edible insects have been conducted?in vitro. The available?in vivo?evidence stems mainly from rodent models. Anti-obesity effects of various edible insect species, such as?Tenebrio molitor,?Hermetia illucens, and?Acheta domesticus, have been suggested, and the findings of studies in mice models suggest the presence of bioactive compounds in edible insects with a potential efficacy in weight control. The mechanisms suggested to underlie the lipid-lowering and anti-obesity effects of edible insect extracts include the inhibition of pathways related to lipid metabolism, downregulation of genes involved in the metabolism of adipose tissue, effects on gut microbiota and increased satiety following consumption of insect-derived food products. However, any claims of health benefits of insect-derived compounds need to be sufficiently established, and trials in humans are a prerequisite. With respect to anti-obesity (and other health) effects, no such compound identified in insects has thus far been tested in humans. Further studies of the effects of bioactive compounds contained in edible insects on human health are therefore needed in order to validate the potential of edible insects as a novel measure in combatting obesity and promoting health in general.

內容: Meat and its products, rich in protein, are one of the important potential sources of antioxidant peptides. However, reviews on the generation and application of meat-derived antioxidant peptides are still limited. To understand the research and application progress of meat-derived antioxidant peptides, the main formation pathways and their commercial applications are exhibited, the research methods for the isolation, purification, and identification are summarized, and the influencing factors, evaluation methods, and intestinal absorption pathways are presented in this work. It is summarized that limited degradation by exogenous and endogenous enzymatic hydrolysis is the main pathway for the production of animal-derived antioxidant peptides. Traditional separation, purification, and identification techniques are also applicable to animal-derived antioxidant peptides. The formation of animal-derived antioxidant peptides is affected by many factors, and the intestinal absorption pathways of antioxidant peptides are different. Finally, insufficient and future development directions are provided.

內容: A growing product on the worldwide dairy market is ultra-high temperature (UHT) milk, which can be kept at room temperature for 6 to 9 months. As the milk undergoes either direct or indirect UHT treatment at 140 ℃ for a few seconds, could kill the majority of bacteria and heat-resistance enzymes. The whey protein in milk will experience a series of physiochemical reactions such as denaturation, proteolysis, age gelation, sedimentation and Maillard after UHT treatment and following storage. The aims of this review were to screen occurred reactions in whey protein, allocate the generated flavor and analysis the volatile compounds. This review explained the mechanisms of the physiochemical reactions, and analysed the related flavor and relevant compounds of the flavor. Also, proposing several suggestions to improve UHT milk quality and find out suitable treatment conditions to prevent or minimize the effects of UHT on whey proteins.

內容: The impact of high hydrostatic pressure (HHP) combined with moisture regulators (MR) on the quality and flavor attributes of beef jerky during storage was investigated in this study. During storage, moisture content decreased in all the treatments, and it was significantly higher in MR + HHP samples than in HHP and control samples (P?< 0.05). At 0 and 15 days, the water activity was approximately 0.7, and at 60 days, it decreased to 0.652 for control samples and 0.678 for MR + HHP samples. During storage, the MR + HHP samples had lower shear force and thiobarbituric acid reactive substances (TBARs) value than the control and HHP samples (P?< 0.05). MR + HHP increased the formation of volatile compounds derived from spices while inhibiting the formation of volatile compounds derived from lipid oxidation. The sensory scores of MR + HHP samples for tenderness, color, taste, and flavor were significantly higher than that of the HHP and control samples (P?< 0.05). This study revealed that HHP and MR treatment reduced the quality deterioration of beef jerky during storage.

內容: It is of great significance to improve the gel properties of egg white for their related products. This goal was accomplished by investigating the gel properties of egg white via interacting with pectin and laccase, and revealing their mechanisms. Results showed that 0.06% sugar beet pectin (SBP) and 0.5 U/g laccase could endow egg white gels with better texture properties (with the highest hardness of 1 508.00 g, chewiness of 1 144.83, and gumminess of 1 210.57), and superior water holding capacity (WHC) (the highest WHC value of 72.08%). This was attributed to the fact that 0.06% of SBP filled the pores of egg white gel, and enhanced affinity and binding of the gels to water by the good hydrophilicity of SBP, and the decrease in egg white gel pore size. Laccase (0.5 U/g) could promote the cross-linking between the egg white gel and SBP to form a more complex gel network structure through the interactions between the tyrosine residues and ferulic acid in SBP, which brought more ionic bonds (22.47%), hydrogen bonds (12.4%), disulfide bonds (16.97%) and more compact structure to egg white gels. This work can provide an effective method to improve the quality of egg white gel and related products.

內容: Proteins play a substantial role in the deterioration of partial freezing shrimp product quality. In this study, traditional protein indicators were used to determine changes in shrimp muscle quality during storage, and the changed proteins were identified using proteomic analysis. The decrease in total sulfhydryl (SH) content and the increase in carbonyl content indicate protein is denatured. The decrease in Ca2+-ATPase activity and the increase in surface hydrophobicity also indicate protein denatured. The increase of hydrophobic interaction and disulfide bonds suggest a larger and closer network among proteins. A total of eight changed protein bands were detected on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) diagram under partial freezing storage. Three of them were identified as?α-actinin (97 kDa), invertebrate connectin (I-connectin (55 kDa)), and troponin I (30 kDa), respectively, which are essential components of myofibrillar protein. The results of the bioinformatic analysis showed that?α-actinin and troponin I are unstable proteins with a secondary structure dominated by?α-helix, while I-connectin is a stable protein with a secondary structure dominated by random coil. All three proteins are hydrophilic and predicted to be non-toxic on ToxinPreds.

內容: Freeze-drying technology is widely used in strain preservation. To further improve the survival rate of?Lactobacillus plantarum?SJ-4 after freeze-drying, an experimental design based on the Plackett-Burman method, steepest ascent hill climbing, and the Box-Behnken response surface methodology (RSM) was used to obtain the freeze-dried powder with a viable bacteria count of 1010?CFU/g. The lyophilized powder of?L. plantarum?SJ-4 prepared was applied to fermented tenderloin ham. High-throughput sequencing was used to analyze the structural changes and succession patterns of bacterial communities and discuss the effects of inoculation on the bacterial phase in tenderloin ham. The results showed that this direct-vat-set starter can improve the fermented meat flora and promote the production of beneficial bacteria, providing a theoretical basis for the in-depth development of the functional properties of the strains and the deep processing of meat products in the future.

內容: The aim of this study was to investigate the effect of different content of sodium chloride (NaCl) on lipid oxidation of chicken breast meat and the endogenous pro-oxidants/antioxidants contributing to lipid oxidation. The results demonstrated that NaCl could promote lipid oxidation in chicken meat until NaCl content reached up to 4.5%. Generation of reactive oxygen species and H2O2?initiated by NaCl might be responsible for the increased lipid oxidation, and lipoxygenase activity was highly correlated with oxidative stability of meat. However, oxidation of lipid was not negatively correlated with superoxide dismutase, glutathione peroxidase and catalase activity. The sensory evaluation by electronic nose showed an increase in saltiness, richness and umami taste and a decrease in bitterness with increasing NaCl content, but there was no significant change in these sensory ratings when the NaCl content exceeded 3.0%. The volatile compounds obtained by gas chromatography-mass spectrometry (GC-MS) showed that NaCl increased the formation of most flavor components in chicken meat. This study could provide a reference for the control of lipid oxidation in meat and development of low salt meat products.

內容: Reflecting the quality of milk at the molecular level is a frontier technology. The aim of this study was to analyze the polymorphisms of bovine insulin-like growth factor 2 (IGF2), signal transducer and activator of transcription 5A (STAT5A) and clusterin (CLU) genes in the raw milk from 507 Chinese Holstein cow using polymerase chain reaction (PCR)-restriction fragment length polymorphism techniques and to evaluate their correlations with the milk protein content (MPC), milk fat content (MFC), milk lactose content (MLC) and milk total solids content (MTSC). In?IGF2?gene, genotype GG was the most frequent genotype (51.68%) followed by the genotype GT (38.03%) and TT (10.29%). And the genotype TT of?IGF2?gene was superior to the other genotypes in MPC. In?CLU?gene, genotype GG was the most common genotype (63.99%) followed by the genotype GA (34.45%) and AA (1.56%). And the genotype AA of?CLU?gene had greater MFC and MLC, but lower MTSC than GA genotype individuals. For?STAT5A?gene, the frequency of genotype CC and CT was similar (45.30% and 45.08%), while the genotype TT had lowest frequency (9.62%). And the genotype TT of?STA5A?gene had highest MPC and lowest MLC. Thus, screening for the?IGF2,?CLU?and?STAT5A?genes were available for evaluating milk quality and raw milk samples were graded according to the different genotypes.