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The evolution of microbial flora was characterized during the soy whey fermentation process by Tibetan kefir grains by analyzing changes in bacterial and fungal community structures using amplicon sequencing. Moreover, changes in physicochemical indexes and active components were monitored. Acidity, pH, and oligosaccharides got a dramatic decline after 30 h of fermentation, while the aglycones isoflavones significantly increased which resulted in a noticeable increase of DPPH· scavenging ability from 53.0% to 70.2%, and many new aromatic volatile compounds were produced. Yeasts, lactic acid bacteria, and acetic acid bacteria grew to more than 7 log CFU/ml after fermentation. The relative abundance of Lactobacillus and Acetobacter changed dramatically in fermented soy whey, which can be ascribed to the increase in aglycone isoflavones levels, especially genistein. This research may deepen the understanding of the mechanism in the fermentation of soy whey by Tibetan kefir grains, and provide a scientific basis for the utilization of soy whey. Novelty impact statement: The fermentation process of soy whey by Tibetan kefir grains was studied. Yeasts, lactic acid bacteria, and acetic acid bacteria grew to more than 7 log CFU/ml after fermentation, and Acetobacter became the dominant genus. Aglycone isoflavones and amino acid nitrogen significantly increased, and DPPH· scavenging ability increased to 70.2%. In addition, new aromatic volatile compounds were produced. [ABSTRACT FROM AUTHOR]

The gel properties of silver carp (Hypophthalmichthys molitrix) surimi fortified with 0.1% PHP were investigated. The addition of 0.1% Psylluium husk powder (PHP) significantly increased the water‐holding capacity (WHC) of the surimi gels, which was associated with the increase in hydrophobic interaction and disulfide bond content (p <.05). A slight decrease in freezing point and non‐freezing bound water content and a increase in the content of water molecules in the gel network compared to the gels without PHP were observed. Gels containing 0.1% PHP had a smoother and firmer surface structure. The breaking force of the gel with PHP increased and the deformation decreased (p <.05) compared with the traditional gels (no PHP, heating at 40°C for 1 hr). Therefore, the addition of PHP affected the WHC of surimi gel. This study may provide some references for the application of PHP in healthy surimi products. Novelty impact statement: PHP provides health benefits as it is rich in dietary fiber; however, to date, there have been few studies regarding the effects of PHP on the gel properties of surimi products. Our result showed that a small amount of PHP (0.1%) improved WHC and water distribution of surimi gels, resulting in a gel with a smoother and more uniform surface. Therefore, this work is meaningful for the promotion of surimi gel properties and the development of healthy surimi products by adding PHP as a potential food ingredient. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of storage time on the sensory and biochemical properties as well as the bacterial community composition of the vacuum‐packaged crab meat shucked by high pressure processing (300 MPa/20 min/25°C) stored at 4°C for 8 days. The aerobic plate count (APC), total volatile base nitrogen (TVBN), and histamine content of crab meat reached 5.71 log CFU/g, 24.50, and 0.99 mg/100 g, respectively, on the 8th day, which was below the reference limit. However, the storage limit was recommended to be 6 days by the sensory evaluation. Among quality indicators, the electronic conductivity presented good correlations with APC, TVBN, histamine content, pH, thiobarbituric acid‐reactive substances (TBARS) value, and sensory evaluation. High‐throughput sequencing showed that the community composition at day 8 was obviously varied from that of the others, and Clostridium was found to be the dominant bacteria at the end of the storage. Industrial relevance: It has been confirmed that HPP shucking has great potential in the segmentation process of crustaceans. HPP shucking can maintain the fresh state of the crab meat and save energy in comparison to the conventional treatment, which could meet the consumers' demand for fresh and minimally processed seafood products. In this work, the shelf life of HPP‐shucked crab meat stored at 4°C was evaluated to be 6 days and Clostridium was dominant in the spoiled meat. These results can provide basic knowledge for the storage and distribution of HPP‐shucked crab meat. Novelty impact statement: The storage quality of HPP‐shucked crab meat was studied, and shelf life of the HPP‐shucked crab meat stored at 4°C was 6 days. The microbial composition at day 8 differed from that of previous time points, and Clostridium was the predominant genera. The electronic conductivity had a good correlation with other indicators. [ABSTRACT FROM AUTHOR]

The effects of high pressure (100–500 MPa) pretreatment on the properties of reduced salt (1.5% of NaCl, w/w) surimi (RSS) containing 0.8% (w/w) κ‐carrageenan (RSS‐K) gels were investigated. Results showed that the gel strength and water‐holding capacity of RSS‐K gels obtained the maximum value at 300 MPa. The low‐field nuclear magnetic resonance revealed that pretreatment at 300 MPa shortened the T2 spin–spin relaxation time of RSS‐K gels and increased the proportion of immobilized water in gels. Scanning electron microscopy imaging suggested that the 3D network structure of RSS‐K gels became smoother, more continuous and uniform, and denser at 300 MPa. These results indicated that pretreatment at 300 MPa could improve the gel properties by changing the water state and microstructure of RSS‐K gels. Practical applications: Consumers' growing awareness of the reduction of NaCl intake has led the aquatic product processing industry to develop healthier surimi‐based products with lower NaCl. However, the gel‐forming ability of surimi is reduced by less NaCl, so effective technologies are required to facilitate gelation for the improvement of the gel properties. Adding κ‐carrageenan (dietary fiber) and high pressure processing can be a potential method to improve the gel quality of reduced NaCl surimi gel. [ABSTRACT FROM AUTHOR]