Department of Biotechnology, University of Verona, Strada Le Grazie 15, Ca' Vignal 2, 37134 Verona, VR, Italy.
Department of Biotechnology, University of Verona, Strada Le Grazie 15, Ca' Vignal 2, 37134 Verona, VR, Italy; VUCC-DBT, Verona University Culture Collection - Department of Biotechnology, University of Verona, Strada Le Grazie 15, Ca' Vignal 2, 37134 Verona, VR, Italy.
Food Res Int. 2023 Dec;174(Pt 1):113550. doi: 10.1016/j.foodres.2023.113550. Epub 2023 Oct 4.
Microbial diseases are of major concern in vitiviniculture as they cause grape losses and wine alterations, but the prevention with chemical substances represents a risk to human health and agricultural ecosystem. A promising alternative is the biocontrol and bioprotection activity of non-Saccharomyces yeasts, such as Metschnikowia pulcherrima, which also presents positive oenological traits when used in multistarter fermentations. The aim of this study was to assess the impact of a selected M. pulcherrima strain in the post-harvest withering and vinification of Garganega grapes to produce the sweet 'passito' wine Recioto di Gambellara DOCG (Italy). M. pulcherrima was firstly inoculated on grape at the beginning of the withering process, and afterwards in must for multistarter sequential microfermentation trials with Saccharomyces cerevisiae. Microbiological, chemical, and sensory analyses were carried out to monitor the vinification of treated and control grapes. Grape bunches during withering were a suitable environment for the colonization by M. pulcherrima, which effectively prevented growth of molds. Differences in grape must composition were observed, and the diverse inoculation strategies caused noticeable variations of fermentation kinetics, main oenological parameters, wine aroma profile, and sensory perception. M. pulcherrima proved effective to protect grapes against fungal infections during withering and contribute to alcoholic fermentation generating wine with distinguished aromatic characteristics.
微生物病害是葡萄栽培中的主要关注点，因为它们会导致葡萄损失和葡萄酒变质，但化学物质的预防措施对人类健康和农业生态系统构成风险。一种有前途的替代方法是非酿酒酵母的生物防治和生物保护活性，例如膜醭毕赤酵母，当用于多 starters 发酵时，它还具有积极的酿造特性。本研究的目的是评估选定的膜醭毕赤酵母菌株在后收获期对 Garganega 葡萄枯萎和酿造甜型“passito”葡萄酒 Recioto di Gambellara DOCG（意大利）的影响。首先在枯萎过程开始时将膜醭毕赤酵母接种到葡萄上，然后在酵母多 starters 顺序微发酵试验中接种到葡萄汁中。进行了微生物学、化学和感官分析，以监测处理和对照葡萄的酿造过程。在枯萎过程中，葡萄串为膜醭毕赤酵母的定殖提供了适宜的环境，有效地防止了霉菌的生长。观察到葡萄汁成分的差异，不同的接种策略导致发酵动力学、主要酿造参数、葡萄酒香气特征和感官感知的明显变化。膜醭毕赤酵母有效地保护了葡萄免受枯萎过程中的真菌感染，并有助于酒精发酵，生成具有独特香气特征的葡萄酒。
