脯氨酰内肽酶水解啤酒蛋白的研究

Study on Hydrolysis of the Protein in Beer by Prolyl Endopeptidase

将脯氨酰内肽酶(PEP)添加在啤酒后酵液中,通过冷混浊实验分析脯氨酰内肽酶对啤酒非生物稳定性的影响。结果表明,添加5mg/L的脯氨酰内肽酶就能有效地提高啤酒的非生物稳定性;采用75%硫酸铵沉淀啤酒蛋白,进行SDS-PAGE电泳分析,结果显示,啤酒蛋白电泳图谱的分布主要表现为8～14.4 ku的窄带和35～45 ku的宽带,而经脯氨酰内肽酶处理的啤酒蛋白电泳图谱中8～14.4 ku的条带消失,说明此蛋白被脯氨酰内肽酶水解。

Non-biological stability was analyzed by cold haze trial through adding the prolyl endopeptidase （PEP） to the fermented wort. The results showed that 5 mg/L prolyl endopeptidase could effectively improve non-biological stability of beer. The proteins in beer were precipitated with 75% ammonium sulfate, and analyzed by SDS-PAGE. The results showed that proteins in the beer was composed of 8-14.4 ku and 35-45 ku bands. The disappearance of the band 8-14.4 ku in the sample when added prolyl endopeptidase indicated that the protein in the beer was hydrolysed by Prolyl endopeptidase.