Dilmetz Brooke A, Brar Gurpreet, Desire Christopher T, Meneses Jon, Klingler-Hoffmann Manuela, Young Clifford, Hoffmann Peter
Clinical & Health Sciences, University of South Australia, Adelaide, SA 5000, Australia.
Coopers Brewery Ltd., Regency Park, SA 5010, Australia.
Foods. 2024 Aug 19;13(16):2593. doi: 10.3390/foods13162593.
Bottle conditioning of beer is an additional fermentation step where yeast and fermentable extract are added to the beer for carbonation. During this process, yeast must overcome environmental stresses to ensure sufficient fermentation in the bottle. Additionally, the yeast must be able to survive for a prolonged time, as a decline in viability will lead to alterations in the product. Here, we investigated the effects of bottle conditioning on beer using six different yeast strains from the brewing, wine making, and distilling industries over 120 days. The ale and lager strains resulted in a beer possessing typical characteristics of a pale ale-style beer, whereas sparkling wine and distilling yeast strains resulted in aromas that were uncharacteristic, which was expected. In addition, we observed that the various strains had different propensities to survive during bottle conditioning. Proteomic analysis was performed to ascertain protein abundance changes and reveal biological processes that potentially enabled specific yeast strains to survive longer during secondary fermentation. Our results showed that proteins associated with oxidoreductase activity and mitochondrial ribosomes were increased in the yeast strain with superior survival and were able to respond to cellular stress more effectively, whereas proteins associated with cell wall modulation were increased in the strain with poor survival characteristics. Overall, we demonstrated the impact of yeast selection on bottle conditioning and the biological processes involved in yeast physiology under these conditions.
啤酒的瓶内二次发酵是一个额外的发酵步骤，在此过程中，会向啤酒中添加酵母和可发酵提取物以进行碳酸化。在此过程中，酵母必须克服环境压力以确保在瓶内充分发酵。此外，酵母必须能够长时间存活，因为活力下降会导致产品发生变化。在这里，我们使用来自酿造、葡萄酒酿造和蒸馏行业的六种不同酵母菌株，对啤酒瓶内二次发酵120天的效果进行了研究。艾尔和拉格酵母菌株酿造出的啤酒具有典型的淡色艾尔风格啤酒的特征，而起泡葡萄酒和蒸馏酵母菌株酿造出的啤酒具有非典型的香气，这是意料之中的。此外，我们观察到不同菌株在瓶内二次发酵期间的存活倾向不同。进行了蛋白质组学分析，以确定蛋白质丰度变化，并揭示可能使特定酵母菌株在二次发酵期间存活更长时间的生物学过程。我们的结果表明，在存活能力较强的酵母菌株中，与氧化还原酶活性和线粒体核糖体相关的蛋白质增加，并且能够更有效地应对细胞应激，而在存活特性较差的菌株中，与细胞壁调节相关的蛋白质增加。总体而言，我们证明了酵母选择对瓶内二次发酵的影响以及在这些条件下酵母生理学所涉及的生物学过程。
