不同添加物对大麦发芽过程中热稳定蛋白含量的影响

为了解发芽过程中热稳定蛋白动态变化趋势，以澳麦为原料，模拟工业制麦条件，系统分析了麦芽制备过程中热稳定蛋白分布变化。通过在浸麦最后一天添加Mg2+、K+、赤霉素(GA3)调节蛋白酶酶活及分解。采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)电泳和考马斯亮蓝法(Bradford法)，研究添加金属离子及赤霉素后热稳定蛋白分布及含量。结果表明，麦芽中热稳定蛋白分子质量主要分布在约40 ku和10 ku两个区域。经制麦后，40 ku分子质量蛋白质含量增加，10 ku附近蛋白质含量变化不明显。Mg2+和赤霉素添加降低了热稳定蛋白含量，K+有利于热稳定蛋白含量增加。

Effects of different additives on heat-stable proteins content in malting process

In order to know the dynamic changes of heat-stable proteins during malting process, the heat-stable proteins were studied under simulated condition in industry. The protease activity and protein degradation were regulated by adding Mg2+, K+ and gibberelin (GA3) at the last day of malt steeping. The metal ions and GA3 addition on heat-stable protein distribution and contents was studied by SDS-PAGE and Coomassie brilliant blue staining (Bradford) method. Results showed that the heat-stable proteins in malt were mainly distributed in the molecular mass of 40 ku and 10 ku. The content of proteins with molecular mass of 40 ku was significantly increased, while the contents of proteins with molecular mass of 10 ku was not obviously changed after germination. The heat-stable proteins contents were decreased by adding Mg2+ and GA3, while they were increased by adding K+.