Brettanomyces bruxellensis, essential contributor in spontaneous beer fermentations providing novel opportunities for the brewing industry

摘要

Recently, the non-conventional, wild yeast Brettanomyces, with B. bruxellensis (teleomorph Dekkera bruxellensis) as the most commonly encountered species, has gained more and more attention in academic research as well as the food and beverage industry. Brettanomyces is a distant relative of the classic brewing yeast Saccharomyces cerevisiae and is especially known for its ambiguous role in food and beverage fermentations. Whilst still mainly considered a spoilage organism responsible for off-flavor production in wine, cider and dairy products, Brettanomyces yeasts can also add desirable flavors to fermented beverages such as lambic and gueuze beers, accounting for many of the typical organoleptic characteristics of the beer. Today, the unique aromatic properties of Brettanomyces and its opportunities for beer brewing are increasingly recognized, with more and more (artisan) brewers adding it deliberately to their fermentations. In this review, we give a comprehensive overview of the currently available information on Brettanomyces yeasts with relevance for the brewing sector, emphasizing B. bruxellensis. First, the history and taxonomy of Brettanomyces is discussed. Secondly, we discuss the dual role of the yeast in fermented beverages by contrasting its role in beer and wine: in certain beer styles it plays a crucial role, in wine it is considered one of the most important spoilage microbes. In this regard we also discuss some of its most important phenotypic characteristics for the food and beverage industry, including flavor and off-flavor production, and focus on its capability to thrive in industrial fermentations. Finally, we review the most important detection and identification methods and address some opportunities for the brewing industry exploiting Brettanomyces yeasts.