Myofibrillar Protein Interacting with Trehalose Elevated the Quality of Frozen Meat

Inhibitive effect of trehalose and sodium pyrophosphate on oxidation and structural changes of myofibrillar proteins in silver carp surimi during frozen storage

This work investigated the cryoprotective effect of trehalose (TH) and sodium pyrophosphate (SPP) alone and in combination on myofibrillar protein (MP) oxidation and structural changes in silver carp surimi during 90 days of frozen storage (-20 °C). TH combined with SPP was significantly more effective than single TH or SPP in preventing MP oxidation (P < 0.05), showing a higher SH content (6.05 nmol/mg protein), and a lower carbonyl (4.24 nmol/mg protein) and dityrosine content (1280 A.U.). SDS-PAGE results indicated that TH combined with SPP did not differ significantly from TH and SPP in inhibiting protein degradation but was more effective in inhibiting protein crosslinking. Moreover, all cryoprotectants could stabilise the secondary and tertiary structures and inhibit unfolded and aggregation of MP, with the combination of TH and SPP being the best. It's worth noting that TH combined with SPP had a synergistic effect on inhibiting the decrease in α-helix content and gel-forming ability, and the increase in surface hydrophobicity. Overall, TH combined with SPP could significantly inhibited MP oxidation and structural changes in surimi during frozen storage and improve the gel-forming ability, which was significantly better than single TH or SPP.

Effect of Artemisia sphaerocephala krasch gum on the functional properties of pork batters

The influence of the incorporation of Artemisia sphaerocephala krasch gum (ASK gum; 0-0.18%) on the water holding capability (WHC), texture, color, rheological property, water distribution, protein conformation and microstructure of pork batters was investigated. The results showed that the cooking yield, WHC and L* value of pork batter gels significantly increased (p < .05) with the increasing incorporation of ASK gum, and the highest value were observed at 0.15%; the a* value decreased significantly (p < .05) and no significance was obtained in b* value (p > .05); the hardness, elasticity, cohesiveness and chewiness increased first and then decreased, and reached the highest value at 0.15%. The rheological results showed that the higher G' value was obtained in pork batters by the incorporation of ASK gum; the low field NMR analysis indicated that ASK gum significantly increased the proportion of P2b and P21 (p < .05) and decreased the proportion of P22 ; Fourier transform infrared spectroscopy (FTIR) indicated that the ASK gum significantly reduced the α-helix content and increased the β-sheet content (p < .05). Scanning electron microscopy results suggested that the incorporation of ASK gum could promote the formation of a more homogeneous and stable microstructure of pork batter gels. Therefore, appropriate incorporation (0.15%) of ASK gum may improve the gel properties of pork batters, and while excessive incorporation (0.18%) could weaken the gel properties.