Performance and Sensory Impacts of <i>Brettanomyces</i> Yeasts from Different Origins During Primary and Secondary Beer Fermentations

<i>Brettanomyces</i> yeasts are a feature of uninoculated traditional lambic and farmhouse style ales that undergo extended maturation in wooden barrels, where they contribute to characteristic aroma profiles through production of volatile phenols. Over recent years, the potential of these yeasts to generate unique beers has seen some brewers experiment with them for primary alcoholic fermentation and bottle conditioning. In contrast with the vast knowledge of <i>Saccharomyces cerevisiae</i> strain-level impact on fermentation outcomes and sensory properties of beer, to date there has been little research comparing performance of <i>Brettanomyces</i> strains from different origins. In this study, we evaluated the fermentation performance and sensory impacts of five <i>Brettanomyces</i> strains originally isolated from beer, three from wine and one from soft-drink, in both primary and secondary fermentations. Malt sugar utilization was significantly stronger for beer-origin strains, particularly in primary fermentation, while volatile phenols concentrations were generally higher for non-beer strains. Both factors were important determinants of beer sensory properties, though there was little correspondence between outcomes of primary and secondary fermentations for particular strains. These results underscore the importance of strain selection for brewing applications and contribute to the growing body of knowledge concerning <i>Brettanomyces</i> evolution and domestication.酒香酵母属（Brettanomyces）酵母是未接种的传统兰比克啤酒及农舍风格艾尔啤酒的标志性微生物，这类啤酒通常在木桶中进行长时间陈酿，酒香酵母可通过产生挥发性酚类物质赋予啤酒独特的香气特征。近年来，这类酵母在酿造独特风味啤酒方面的潜力促使部分酿酒师尝试将其应用于主酒精发酵与瓶中熟成工艺。相较于对酿酒酵母（Saccharomyces cerevisiae）菌株水平对发酵结果与啤酒感官特性的影响已积累的大量研究，目前针对不同来源的酒香酵母菌株性能的对比研究仍较为匮乏。本研究评估了5株分离自啤酒的酒香酵母菌株、3株分离自葡萄酒以及1株分离自软饮料的酒香酵母菌株在主发酵与二次发酵中的发酵性能与感官影响。啤酒来源的菌株对麦芽糖的利用能力显著更强，尤其在主发酵阶段；而非啤酒来源的菌株所产生的挥发性酚类物质浓度通常更高。这两个因素均是决定啤酒感官特性的重要因素，不过特定菌株在主发酵与二次发酵中的表现几乎不存在相关性。本研究结果凸显了菌株筛选在酿酒应用中的重要性，同时为日益扩充的酒香酵母演化与驯化相关研究成果提供了新的支撑。