蛋白分离方式对鱼肉蛋白质组成和功能特性的影响

Effects of Extraction Methods on the Composition and Functional Properties of Fish Proteins

为了研究2种不同蛋白分离方式对蛋白质组成和功能特性的影响,以白鲢背部肌肉、漂洗鱼糜蛋白和ISP分离蛋白为研究对象,研究其氨基酸组成、蛋白质模式、粒径分布、Zeta电位、保水性、乳化性和表面疏水性的差异。结果表明,与白鲢背部肌肉相比,ISP分离蛋白的总氨基酸含量没有损失,而漂洗鱼糜蛋白的总氨基酸含量减少;SDS-PAGE凝胶电泳表明,与背部肌肉的蛋白质组成相比,漂洗方式会使鱼肉的40kDa原肌球蛋白(TM)、50kDa肌钙蛋白(TN)和25kDa肌球蛋白轻链(MLC)消失,而ISP蛋白分离法没有造成明显的组分损失。在蛋白质的功能特性方面,ISP提取蛋白的粒径分布范围较漂洗鱼糜蛋白广,而Zeta电位二者间没有显著性差异(p>0.05);漂洗鱼糜蛋白其持水性显著高于ISP提取蛋白(p<0.05);ISP提取蛋白乳化活性指数(EAI)显著低于漂洗鱼糜蛋白,但其乳化稳定指数(ESI)显著高于漂洗鱼糜蛋白(p<0.05);ISP提取蛋白的表面疏水性(S0-ANS)显著高于漂洗鱼糜蛋白(p<0.05)。综合分析可知,蛋白分离方式会显著影响鱼肉蛋白质的组成,且ISP蛋白分离方式一定程度上改善了鱼肉蛋白的功能特性。

In order to study the effects of two different protein extraction methods on composition and functional properties of fish protein,this paper investigated the amino acid composition,protein pattern and diameter distribution,zeta potential,water retention capacity,emulsifying property and surface hydrophobicity of the dorsal muscle,surimi protein and ISP protein of silver carp.The results showed that compared with the back muscle of the silver carp,the total amino acid content of the ISP protein was less lost,while that of the surimi protein was greatly reduced.SDS-PAGE gel electrophoresis also showed that the bands of 40 kDa tropomyosin (TM),50 kDa troponin (TN) and 25 kDa myosin light chain (MLC) were disappear by washing method,comparing with the dorsal muscle of silver carp.In terms of functional properties of proteins extracted by two different methods, ISP protein distributed in a wider range than surimi protein,but there was no significant difference between zeta potential (p>0.05).The water holding capacity of surimi protein was significantly higher than that of ISP protein (p<0.05).Emulsification activity index (EAI) of ISP protein was significantly lower than rinsed protein,but its emulsion stability index (ESI) was significantly higher than that of surimi protein (p<0.05).The surface hydrophobicity (S0-ANS) of ISP protein was significantly higher than that of the washed surimi protein (p<0.05).Consequently,the protein composition and functional properties were significantly affected by the method of protein extraction,and the functional properties of ISP protein were improved to a certain extent.