氨基酸含量对啤酒发酵的影响.doc

目 录 前言 1 1啤酒中氨基酸的来源 2 2啤酒中氨基酸的分类 3 3氨基酸含量对啤酒发酵过程中风味物质形成的影响 4 3.1氨基酸含量对高级醇形成的影响 4 3.1.1高级醇的形成 4 3.1.2氨基酸与高级醇形成的关系 5 3.1.3控制啤酒中高级醇含量的方法 6 3.2氨基酸含量对双乙酰形成的影响 6 3.2.1双乙酰的形成 6 3.2.2氨基酸与双乙酰形成的关系 6 3.2.3降低啤酒中双乙酰含量的方法 7 3.3氨基酸含量对硫化氢形成的影响 8 3.3.1硫化氢的形成 8 3.3.2氨基酸与硫化氢形成的关系 8 3.3.3降低啤酒中硫化氢含量方法 9 3.4氨基酸含量对醋形成的影响 9 4结论 9 参考文献 11 致谢 12  摘 要 啤酒中含有多种氨基酸，对啤酒的口感和品质有着一定的决定性作用，分析啤酒中游离氨基酸含量的多少可以反映其营养状况。主要原因是氨基酸含量对啤酒发酵过程中风味物质的形成有着一定的影响，最密切的风味物质主要是高级醇、双乙酰、硫化氢、酯、有机酸等。本文主要讨论了麦汁中氨基酸含量对啤酒酵母代谢副产物高级醇、双乙酰、硫化氢及酯含量的影响及啤酒质量的影响。结果表明：麦汁中氨基酸含量过高或过低都会使高级醇生成量增加，当氨基酸含量控制在适宜条件时，有利于降低高级醇生成量和提高发酵度；不同氨基酸对总双乙酰水平的影响差异很大（缬氨酸、亮氨酸、异亮氨酸在降低双乙酰含量方面效果显著；精氨酸、组氨酸、谷氨酰胺、赖氨酸、丝氨酸在降低总双乙酰含量方面起到了明显的反作用）；麦汁中不同的氨基酸含量对啤酒发酵中硫化氢的形成均有不同程度的影响，影响最大的是半胱氨酸与甲硫氨酸。 关键词：氨基酸；高级醇；双乙酰；硫化氢 Abstract In the beer includes many kinds of amino acids, having certain decisive effect to the beer feeling in the mouth and the quality. The analysis to amino acids content in beer may reflect its nutritional status. Main reason was that the amino acids content had certain influence to the formation of flavor material in the beer fermentative process, and the closest flavor material were mainly higher alcohols, the diacetyl, the hydrogen sulfide, the ester, the organic acid and so on. This study mainly discussed the amino acids content in wort to the influence of beer yeast metabolism by-product higher alcohols, the diacetyl, the hydrogen sulfide and the ester content and the beer quality. The result indicated: amino acids content in wort too high or too low made the quantity of higher alcohols to increase,and it was advantageous in reducing the higher alcohols quantity and enhancing the degree of fermentation when amino acid content was controlled in suitable condition; the production of the total diacetyl was really different by the different amino acids (the amino-isovaleric acid, the leucine, the isoleucine to reduce the diacetyl content were remarkable; while the arginine, the histidine, the valley ammonia amide, the lysine, the serine to reduce th