Abstract：
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.
摘要：
这项工作研究了海藻糖（TH）和焦磷酸钠（SPP）单独和联合使用对90天冷冻储存（-20°C）期间silver鱼糜肌原纤维蛋白（MP）氧化和结构变化的冷冻保护作用。TH联合SPP在预防MP氧化方面明显优于单一TH或SPP（P<0.05），显示较高的SH含量（6.05nmol/mg蛋白质），和较低的羰基(4.24nmol/mg蛋白质)和二酪氨酸含量(1280A.U.)。SDS-PAGE结果表明，TH与SPP组合在抑制蛋白质降解方面与TH和SPP没有显着差异，但在抑制蛋白质交联方面更有效。此外，所有冷冻保护剂都可以稳定二级和三级结构，并抑制MP的展开和聚集，TH和SPP的组合是最好的。值得指出的是,TH与SPP联用对抑制α-螺旋含量的降低和凝胶形成能力具有协同作用,和表面疏水性的增加。总的来说,TH与SPP联用能显著抑制鱼糜在冷冻保存过程中的MP氧化和结构变化，提高其凝胶形成能力。显著优于单一TH或SPP。
