Yuan Li, Yu Jiamei, Mu Jianlou, Shi Tong, Sun Quancai, Jin Wengang, Gao Ruichang
School of Food and Biological Engineering, Jiangsu University No. 301, Xuefu Road Zhenjiang Jiangsu Province 212013 China
Bio-resources Key Laboratory of Shaanxi Province, School of Biological Science and Engineering, Shaanxi University of Technology Hanzhong 723001 P R China
RSC Adv. 2019 Jun 25;9(34):19828-19836. doi: 10.1039/c9ra03517f. eCollection 2019 Jun 19.
This work studied the effects of KGM with different degrees of deacetylation (DDs) on the physicochemical properties of silver carp () surimi gels. Compared with KGM, deacetylated KGM (DKGM) weakened the water-holding capacity, but increased the gel strength of surimi gels. The storage modulus (') and loss modulus ('') of surimi showed an upward trend, and the aggregation rate of surimi with DKGM changed. The number of ionic bonds of mixed surimi gels increased on the whole, but those of hydrogen bonds declined; a hydrophobic interaction was the main driving force, and improved with the DDs of DKGM. FT-IR results indicated that the deacetylation of KGM had a slight influence on the secondary structure of the proteins. SDS-PAGE results showed that DKGM enhanced the intensity of the main heavy chains of myosin and actin. Examination of the network structure of the surimi gels revealed that DKGM might combine around the filaments of myofibrillar proteins like a rosary through hydrophobic interactions and hydrogen bonding. As a consequence, the myfibrillar protein aggregation was changed and the microstructures of the surimi became more compact and fibrous. The results indicated that the deacetylation of KGM led to an increase in hydrophobicity, which influenced the hydrophobic interaction of the myofibrillar proteins. As a result, the aggregation of the myofibrillar proteins was promoted and the physico-chemical properties of the surimi gel were improved.
本研究考察了不同脱乙酰度（DDs）的魔芋葡甘聚糖（KGM）对鲢鱼鱼糜凝胶理化性质的影响。与KGM相比，脱乙酰化魔芋葡甘聚糖（DKGM）削弱了鱼糜凝胶的持水能力，但提高了其凝胶强度。鱼糜的储能模量（G'）和损耗模量（G''）呈上升趋势，添加DKGM的鱼糜聚集率发生变化。混合鱼糜凝胶的离子键数量总体增加，但氢键数量减少；疏水相互作用是主要驱动力，并随DKGM的脱乙酰度提高而增强。傅里叶变换红外光谱（FT-IR）结果表明，KGM的脱乙酰化对蛋白质的二级结构有轻微影响。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）结果显示，DKGM增强了肌球蛋白和肌动蛋白主要重链的强度。对鱼糜凝胶网络结构的检测表明，DKGM可能通过疏水相互作用和氢键像念珠一样围绕肌原纤维蛋白丝结合。因此，肌原纤维蛋白聚集发生变化，鱼糜的微观结构变得更加致密和呈纤维状。结果表明，KGM的脱乙酰化导致疏水性增加，这影响了肌原纤维蛋白的疏水相互作用。结果，肌原纤维蛋白的聚集得到促进，鱼糜凝胶的理化性质得到改善。
