鱼糜加工漂洗液蛋白质理化特性分析

Protein Physicochemical Properties Analysis of Rinsing Solution for Surimi Processing

为探究鱼糜漂洗液中回收蛋白的再利用加工技术并提供理论分析和指导,对等电点沉降法回收的蛋白、单一褐藻胶絮凝剂沉降回收的蛋白、单一壳聚糖絮凝剂沉降回收的蛋白和褐藻胶-壳聚糖复配絮凝剂沉降回收的蛋白进行理化特性分析,用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳法(Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis,SDS-PAGE)测定回收漂洗液中水溶性蛋白质的纯度、溶解度、乳化稳定性(Emulsion Stability,ES)与乳化活性(Emulsification Activity,EA)。SDS-PAGE电泳图显示以褐藻胶为单一絮凝剂絮凝回收的蛋白谱带最为完整齐全,其回收的蛋白种类是漂洗液中水溶性蛋白质的全部,分子量为8.3~120.2 kDa。在控制的实验pH值内溶解度大多在35%以上,当pH>6.0时回收蛋白都表现出较好的溶解性,溶解度均高于60%。乳化稳定性指数(Emulsion Stability Index,ESI)和乳化性指数(Emulsion Activity Index,EAI)随pH值的变化趋势基本一致,呈现出先下降后上升的趋势,在pH值为6.0~7.0的实验范围,蛋白质的EA和ES则表现最差。

In order to explore the reuse processing technology of recovered protein in surimi rinse and provide theoretical analysis and guidance,the physicochemical properties of the protein recovered by isoelectric point sedimentation method,the protein recovered by the single sodium alginate flocculant,the protein recovered by the single chitosan flocculant and the protein recovered by sodium alginate-chitosan composite flocculant were analyzed,including the purity by sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE),emulsifying stability(ES)and emulsifying activity(EA)of water-soluble protein in the rinse solution.SDS-PAGE electrophoresis shows the band is the most complete ran out with alginate as the single flocculation,the species of recovery proteins are surimi wash water of water-soluble protein in all,the molecular weight range from 8.3 kDa to 120.2 kDa.Within the controlled experimental pH value,the solubility is mostly above 35%.When the pH is greater than 6.0,the recovered protein exhibits good solubility,with solubility exceeding 60%.Emulsion stability index(ESI)and emulsion Activity Index(EAI)value have the same trend with the changing pH value,decreased first and increased later.In the range of pH 6.0~7.0,the protein emulsifying activity and emulsion stability is the worst.