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.

The effects of freezing methods, including rapid freezing (RF) or slow freezing (SF), combined with thawing methods, e.g., water immersing thawing (WT) or cold thawing (CT), on the meat yield, drip loss, gel properties, and digestive properties of meat detached from red swamp crayfish were investigated. RF greatly reduced the freezing time compared to SF, and the thawing time of frozen crayfish was obviously shortened by WT in comparison to CT. RF and CT improved the meat yield but increased the drip loss, probably as a result of the greater protein denaturation or degradation. A soft and flexible gel was obtained by SF-CT, while a hard one was achieved by RF-WT. An SEM analysis showed that SF resulted in rough and irregular microstructures with larger pore sizes. Freeze-thawing led to an increase in the β-sheet content at the expense of α-helix and variations in the microenvironment of tyrosine and tryptophan residues in protein molecules of the gels, which was more pronounced in the SF-CT group. Moreover, freeze-thawing could cause enhanced protein digestibility but reduce the antioxidant activity of gels. These findings underline the promise of the freezing-thawing treatment in tuning the gel-based meat products of crayfish.

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