烟叶烘烤过程中蛋白酶活性及蛋白质变化规律

Change Regulation of Protease Activity and Protein Content in Tobacco during Its Curing Process

采用三段式烘烤工艺,研究烤烟品种K326中、上部烟叶烘烤过程中蛋白酶活性及蛋白质含量的变化规律。结果表明:随着烘烤的进程,中部叶蛋白酶活性呈缓慢上升→快速上升→快速下降→快速上升→快速下降的双峰曲线;烟叶中蛋白质的含量呈持续下降的趋势,但降解速率呈慢→快→慢→快→慢的曲线;蛋白酶活性的变化与蛋白质降解速率的变化呈极显著正相关;上部叶蛋白酶活性及蛋白质含量变化规律与中部叶相似。因此,通过适当延长烘烤变黄时间、提高变黄相对湿度可达到降低烤后上部叶蛋白质含量的目的。

The change regulation of protease activity and protein content in upper and middle tobacco leaves during the curing process was studied by three-step curing technology.The results showed that the protease activity of middle tobacco leaves was the two-peak curve of slow rise→ fast rise→ fast drop→ fast rise→ fast drop,the protein content of middle tobacco leaves appeared the continuous trend but the degradation rate was the curve of slow→ fast→ slow→ fast→ slow,there was a significant positive correlation between protease activity and protein degradation rate,and the change regulation of protease activity and protein content in upper tobacco leaves was similar to that of middle leaves.Therefore,suitably prolonging yellowing time and raising relative humidity can effectively reduce protein content of upper tobacco leaves.