即食小米粥贮藏过程中蛋白组分变化规律的研究

The change rule of protein components during instant millet porridge storage

采用Osborne法对小米及即食小米粥中的清蛋白、球蛋白、醇溶蛋白、谷蛋白进行提取,运用聚丙烯酰胺凝胶电泳法对小米以及贮藏不同时间的即食小米粥中的4种蛋白质进行亚基分析。通过对比小米和即食小米粥蛋白组分发现,即食小米粥中4种蛋白组分的含量都有不同程度的减少,其中醇溶蛋白降幅最大,其次是清蛋白、球蛋白;由电泳图谱可知,即食小米粥加工工序对小米中清蛋白、球蛋白的影响最大,清蛋白和球蛋白的部分亚基随废水排出而损失,剩余亚基通过二硫键形成新的蛋白组分,并以高分子聚集体的形式保存在即食小米粥中。随贮藏时间的延长,即食小米粥中清蛋白、球蛋白、醇溶蛋白和谷蛋白含量及亚基数量均有不同程度的减少,到贮藏12 d时,清蛋白、球蛋白和谷蛋白的亚基条带几乎全部消失。

In this paper, Osborne method was used to extract albumin, globulin, prolamine and gluten from millet and instant millet porridge. Polyacrylamide gel electrophoresis was used to analyse subunits of four proteins in millet porridge for different storage days. By comparing the millet and instant millet porridge protein components, the content of the four protein components in the instant millet porridge was reduced to different extents, among which the prolamine protein decreased the most, followed by the albumin and globulin;as seen from the electropherogram. The processing of instant millet porridge has the greatest influence on the albumin and globulin of millet. Some subunits of albumin and globulin are lost with the discharge of wastewater. The remaining subunits form new protein components through disulfide bonds and aggregate with macromolecules, which is preserved in instant millet porridge. With the prolongation of storage time, the content of albumin, globulin, prolamine and gluten and the number of subunits in the instant millet porridge were reduced to different degrees. When stored for 12 days, the subunit strips of albumin, globulin and gluten were not observed. The band almost disappeared.