Pulvirenti Andrea, Rainieri Sandra, Boveri Silvio, Giudici Paolo
Dipartimento di Scienze Agrarie - Universita degli Studi di Modena e Reggio Emilia, Padiglione Besta, via Amendola 2, 42100 Reggio Emilia, Italy.
Can J Microbiol. 2009 Mar;55(3):326-32. doi: 10.1139/w08-140.
We propose an efficient and time-saving strategy for starter culture selection. Our approach is based on the accomplishment of 3 phases: (i) the selection of yeast strains dominating spontaneous fermentations, (ii) the selection among the dominant strains of those showing the best technological characteristics, and (iii) the final selection among good technological strains of those showing the desired qualitative traits. We applied this approach to wine fermentations, even though the same strategy has the potential to be employed for the selection of any type of starter culture. We isolated and identified yeast strains at the mid- and final stages of 6 spontaneous fermentations carried out in 3 different Spanish wineries. We identified all strains as Saccharomyces cerevisiae by restriction fragment length polymorphism of the ribosomal DNA internal transcribed spacer region, and subsequently distinguished each strain by analyzing the polymorphism of the inter-delta regions. Strains that were detected both at the mid- and final stages of the fermentation were considered dominant. Four dominant strains were finally selected and tested in pilot-scale fermentation, and their performance was compared with that of a commercial wine strain. All dominant strains showed good fitness and resulted suitable to be employed as starter cultures. One of the dominant strains isolated in this study is currently commercialized.
我们提出了一种高效且省时的发酵剂选择策略。我们的方法基于三个阶段的完成：（i）选择主导自然发酵的酵母菌株，（ii）在表现出最佳工艺特性的主导菌株中进行选择，以及（iii）在具有所需品质性状的优良工艺菌株中进行最终选择。我们将此方法应用于葡萄酒发酵，尽管相同的策略有可能用于任何类型发酵剂的选择。我们在西班牙三个不同酒庄进行的6次自然发酵的中期和末期分离并鉴定了酵母菌株。通过核糖体DNA内部转录间隔区的限制性片段长度多态性，我们将所有菌株鉴定为酿酒酵母，随后通过分析δ区间的多态性来区分每个菌株。在发酵中期和末期均检测到的菌株被视为优势菌株。最终选择了4个优势菌株并在中试规模发酵中进行测试，并将它们的性能与一种商业葡萄酒菌株的性能进行比较。所有优势菌株均表现出良好的适应性，结果表明适合用作发酵剂。本研究中分离出的一个优势菌株目前已商业化。
