郫县豆瓣甜瓣子发酵阶段蛋白质组分及降解规律研究

Protein composition and degradation of Pixian board bean paste duringsweet petals fermentation stage

为了解郫县豆瓣甜瓣子发酵阶段蛋白质组成及降解规律,以甜瓣子发酵阶段蚕豆瓣为研究对象,分别取制曲0、3、7 d,盐水发酵15、30、45、60、90 d的样品,研究不同发酵时间下总蛋白和4种蛋白质组分(水溶蛋白、盐溶蛋白、醇溶蛋白、麦谷蛋白)含量变化,并将蛋白亚基、多肽和游离氨基酸变化结合风味物质形成进行分析。结果表明,甜瓣子发酵过程中,总蛋白含量持续下降,从31.25 g/100 g减少到19.17 g/100 g。水溶蛋白和麦谷蛋白含量均呈先上升后下降趋势,发酵结束时分别减少至7.72和6.54 g/100 g。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)结果显示,甜瓣子发酵前30 d以水溶蛋白和麦谷蛋白降解为主,30 d后以水溶蛋白降解为主。在整个甜瓣子发酵阶段,共检出19种游离氨基酸,发酵90 d时游离氨基酸总量增长到50.22 mg/g,其中丙氨酸、谷氨酸、赖氨酸、精氨酸、亮氨酸、缬氨酸含量较高(≥1 mg/g)。甜鲜味、鲜酸味、苦味氨基酸分别增长到11.829、16.140、14.652 mg/g。该研究为提高郫县豆瓣蛋白利用率、增加风味基础物质含量、提升产品品质、改进加工工艺提供了科学依据。

The protein composition and degradation of Pixian board bean paste were studied during sweet petals fermentation.Total protein content and four components(albumin,globulin,prolamin and glutenin of koji preparation(0,3,7 d)and brine fermentation(15,30,45,60,90 d)were studied,and the changes of protein subunits,peptides and free amino acids combined with the formation of flavor substances were analyzed.The results showed that the total protein content decreased from 31.25 g/100 g to 19.17 g/100 g.The contents of albumin and glutenin increased first and then decreased,and reduced to 7.72 g/100 g and 6.54 g/100 g at the end of sweet petals fermentation stage,respectively.Sodium dodecyl sulfate polyacrylamide gel electrophoresis(SDS-PAGE)showed that the degradation of albumin and glutenin was dominant in the first 30 days,and then did albumin.A total of 19 free amino acids were detected.After 90 days of fermentation,the total amount of free amino acids increased by 50.219 mg/g.The free amino acids with a high content throughout the fermentation process were alanine,glutamic acid,lysine,arginine leucine and valine(≥1 mg/g).The umami with sweet taste amino acids,umami with sour taste amino acids,and bitter taste amino acids groups increased to 11.829 mg/g,16.140 mg/g,and 14.652 mg/g,respectively.This study provided scientific basis for improving the utilization rate of protein,increasing the flavor base material content,improving the product quality and the processing technology.