Abstract
In this study, yeasts isolated from filter membranes used for the quality control of bottled wines were identified and tested for their resistance to some cleaning agents and potassium metabisulphite, adhesion to polystyrene and stainless-steel surfaces, and formation of a thin round biofilm, referred to as a MAT. A total of 40 strains were identified by rRNA internal transcribed spacer (ITS) restriction analysis and sequence analysis of D1/D2 domain of 26S rRNA gene. Strains belong to Pichia manshurica (12), Pichia kudriavzevii (9), Pichia membranifaciens (1), Candida sojae (6), Candida parapsilosis (3), Candida sonorensis (1), Lodderomyces elongisporus (2), Sporopachydermia lactativora (3), and Clavispora lusitaniae (3) species. Regarding the adhesion properties, differences were observed among species. Yeasts preferred planktonic state when tested on polystyrene plates. On stainless-steel supports, adhered cells reached values of about 6 log CFU/mL. MAT structures were formed only by yeasts belonging to the Pichia genus. Yeast species showed different resistance to sanitizers, with peracetic acid being the most effective and active at low concentrations, with minimum inhibitory concentration (MIC) values ranging from 0.08% (v/v) to 1% (v/v). C. parapsilosis was the most sensible species. Data could be exploited to develop sustainable strategies to reduce wine contamination and establish tailored sanitizing procedures.
Highlights
The grapevine (Vitis vinifera) phyllosphere and wine musts harbor a complex microbiome, including yeasts, filamentous fungi, and bacteria that modulate grapevine health, growth, and wine fermentation [1,2]
Restriction profile comparisons between isolates and published strains allowed assigning the isolates to Pichia manshurica (12), Pichia kudriavzevii (9), Pichia membranifaciens (1), Candida sojae (6), Candida parapsilosis (3), Candida sonorensis (1), Sporopachydermia lactativora (3), Lodderomyces elongisporus (2), and Clavispora lusitaniae (3) (Table S1)
P. manshurica is common in several fermented foods, and it is usually found in the early stages of spontaneous fermentation of alcoholic beverages, where it was firstly isolated [28]
Summary
The grapevine (Vitis vinifera) phyllosphere and wine musts harbor a complex microbiome, including yeasts, filamentous fungi, and bacteria that modulate grapevine health, growth, and wine fermentation [1,2] During wine fermentation, these microbes interact among them during alcoholic (AF) and malolactic (MLF) fermentations. Apart from S. cerevisiae, recognized as the main fermentative agent, other yeast species, known as non-Saccharomyces yeasts, such as Hanseniaspora/Kloeckera, Pichia, Candida, or Metschnikowia, release metabolites, which influence the chemical environment and/or fermentation process and are implicated in early stages of the AF [4] These microorganisms could originate from the vineyard soil [5,6], air, precipitation (rainfall, hail, snow), be transported by animal vectors (bees, insects, and birds) [7,8,9], and be resident in nearby native forests [6,10]. Wine spoilage yeasts mainly belong to the following genera: Dekkera/Brettanomyces, Candida, Hanseniaspora, Pichia, Metschnikowia, Saccharomycodes, Schizosaccharomyces, and Zygosaccharomyces [13], which can cause film formation in bulk wines, cloudiness, sediment formation, and gas production in bottled
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
