啤酒生产过程中氧化还原酶系的研究

啤酒生产过程中的氧化还原酶与啤酒风味陈化紧密相关。低水分下，其耐温活性远高于其它几种酶，在麦芽中酶活升高比例最大（与大麦中的酶活相比），其在糖化过程中氧化多酚的能力远大于多酚氧化酶。糖化过程中迅速失活，而脂肪酸氧化酶在糖化起始的低温阶段仍有部分酶活，影响不饱和脂肪酸的氧化。焙燥过程中适当延长50～70℃温度段时间，可有效降低麦芽中氧化还原酶的酶活。结合这些酶的性质，从部分抑制它们的活性角度出发，在糖化过程中，于50～60℃进行隔氧处理，可经济、有效的减少影响风味氧化的前驱物质的含量。同一质量等级不同品种的麦芽的氧化还原酶系差别相当大，相应制得的麦汁中与风味氧化有关的物质含量也有较大差别，这可能是造成不同批次原料酿造的成品啤酒风味保鲜期不稳定的原因之一。

Further Studies on Peroxidase, Polyphenol Oxidase, Lipoxygenase, Catalase during Malting and Mashing

The enzymes suggested by the literature to promote oxidation during mashing cancause the substrate to produce a great amount of precursors of staling substances. In theseenzymes, peroxidase is more important than others because of its high heat-resistance andlow substrate-specificity. There are two paths to reduce the effect of them in brewing.First, the reasonable extension of time from 50℃to70℃in kilning can decrease effectively theactivity of these enzymes in malt. Second, the avoidance of oxygen uptake during mashing at50℃and 60℃can economically and effectively decrease the content of the staling precursorsfrom the inhibition of the part of activities of these enzymes. Although these malts have thesame quality standard, the content of these enzymes vary greatly with varieties of malt. It isone of the main reasons that the flavor stability in bottles fluctuate in those plants that oftenchange their raw material.