高浓高温对啤酒酵母发酵性能的影响

以啤酒酵母S-6为实验菌株，研究了主发酵温度和原麦汁浓度对啤酒发酵的残糖、酒精度、风味物质和絮凝性等性能指标的影响。结果表明，原麦汁浓度一定时，主发酵温度对高级醇和乙酸酯的含量影响较大，主发酵温度由10 ℃提高至16 ℃时，高级醇含量提高了10%～20%，乙酸酯含量提高了8%～16%，但CO2累积质量损失、残糖、酒精度和絮凝性基本不受温度的影响；主发酵温度一定时，原麦汁浓度对酵母絮凝性影响较大，原麦汁浓度越高，酵母絮凝性越低，将高浓（18 °Bx）发酵液稀释50%至常浓（12 °Bx），残糖、酒精度和高级醇的含量与常浓发酵液基本相同。该研究为选育高温高浓发酵低产高级醇同时强絮凝性酵母菌株提供了重要依据。

Effects of high gravity and high temperature on fermentation performance of beer yeast

Using beer yeast S-6 as experimental strain, the effects of main fermentation temperature and initial wort gravity on alcohol content, flavor substance, flocculability and other fermentation characters by beer yeast S-6 were studied. The results showed that under certain initial wort gravity, the main fermentation temperature had great effects on higher alcohols and acetic esters. When the main fermentation temperature increased from 10 ℃ to 16 ℃, higher alcohols content increased 10% to 20%, acetic esters increased 8% to 16%, but no effects on total loss of CO2, residual sugar, alcohol content and flocculability. In addition, the initial wort gravity had great effects on flocculability under certain main fermentation temperature; the original wort concentration was higher, while the flocculability of beer yeast was lower. When the high-gravity fermentation broth (18 °Bx) was diluted 50% to the conventional gravity (12 °Bx), there was no significant differences in residual sugar, alcohol content and higher alcohols with common fermentation broth. The research provided an important basis for breeding a low-yielding higher alcohols and strong flocculability beer yeast under high temperature and high gravity fermentation process.