加热处理燕麦分离蛋白对胃蛋白酶水解的影响

Effect of Heat Treatment of Oat Protein Isolate on Pepsin Hydrolysis

采用坝莜1号燕麦为原料进行研究,通过对蛋白质水解度及SDS-PAGE电泳分析发现:未经过加热处理的燕麦分离蛋白水解度较高且更容易水解为小分子质量的亚基。当热处理温度低于70℃时,加热造成蛋白结构解离,破坏了胃蛋白酶作用位点,不利于水解;在70~80℃时,部分燕麦分离蛋白由于加热造成聚集改变其原有蛋白结构,遮蔽了胃蛋白酶作用位点,随着水解时间的延长,部分胃蛋白酶作用位点暴露水解度提高,但由于聚集造成结构改变,大的聚集体很难水解为小分子质量的亚基;110℃加热处理使燕麦分离蛋白形成更大聚集体,同样地,大分子质量的聚集体很难水解为小分子质量的亚基。因此,未经过加热处理的燕麦分离蛋白更容易被人体吸收。

Using Bayou No.1 oatmeal as the raw material,throngh the protein hydrolysis degree and SDS-PAGE electrophoresis analysis found that the oat protein isolate without heat treatment had a higher protein hydrolysis degree and was more easily hydrolyzed into small molecular weight subunits.When the heat treatment temperature is lower than 70℃,the protein structure is dissociated by heating,which destroys the action site of pepsin and is not conducive to hydrolysis.At 70~80℃,some oat protein isolates will change their original protein structure due to aggregation caused by heating,which masks the action site of pepsin,with the extension of the hydrolysis time,the hydrolysis degree increased due to exposure of some pepsin action sites,but the structural changes caused by aggregation,large aggregates are difficult to hydrolyze into small molecular weight subunits.Heat treatment at 110℃makes oat protein isolate form larger aggregates.Similarly,aggregates with large molecular weight are difficult to hydrolyze into subunits with small molecular weight.Therefore,the oat protein isolate without heat treatment is more easily absorbed by the human body.