%0 Journal Article
%T Molecular and Technological Characterization of Saccharomyces cerevisiae Strains Isolated from Natural Fermentation of Susumaniello Grape Must in Apulia, Southern Italy
%A Mariana Tristezza
%A Lorenagostina Fantastico
%A Cosimo Vetrano
%A Gianluca Bleve
%A Daniela Corallo
%A Francesco Grieco
%A Giovanni Mita
%A Francesco Grieco
%J International Journal of Microbiology
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/897428
%X The characterization of autochthonous Saccharomyces cerevisiae strains is an important step towards the conservation and employment of microbial biodiversity. The utilization of selected autochthonous yeast strains would be a powerful tool to enhance the organoleptic and sensory properties of typical regional wines. In fact, indigenous yeasts are better tailored to a particular must and because of this they are able to praise the peculiarities of the derived wine. The present study described the biodiversity of indigenous S. cerevisiae strains isolated from natural must fermentations of an ancient and recently rediscovered Apulian grape cultivar, denoted as ¡°Susumaniello.¡± The yeast strains denoted by the best oenological and technological features were identified and their fermentative performances were tested by either laboratory assay. Five yeast strains showed that they could be excellent candidates for the production of industrial starter cultures, since they dominated the fermentation process and produced wines characterized by peculiar oenological and organoleptic features. 1. Introduction The conversion of grape must into wine is a fermentative process performed by indigenous microorganisms, whose composition notably contributes to the sensorial and chemical properties of the wine. The main role of yeast during must fermentation is to promote the conversion of grape sugars, in particular hexoses, into ethanol, carbon dioxide, and other metabolites without the production of off-flavours. In the spontaneous grape must fermentation indigenous yeasts dynamics occurs, it being the final step always dominated by alcohol-tolerant strains [1]. The dominant yeast species is Saccharomyces cerevisiae and it was demonstrated that the fermentation process is led and completed by a limited number of strains [2]. Moreover, a sequential substitution of strains happens during must fermentation as they progress to higher ethanol concentration [3]. As the importance of S. cerevisiae role in winemaking has long been established, the use of the commercial strains of these yeast cultures in fermentation is an ordinary practice in order to ensure a reproducible product and to reduce the risk of wine spoilage. However, this custom can cause a progressive substitution of local microflora and a consequent reduction of microbial biodiversity. Indeed, knowledge of the autochthonous yeast strains will help to preserve and employ the most representative strains. The selection and the employment of autochthonous microorganisms could be a powerful instrument to improve the
%U http://www.hindawi.com/journals/ijmicro/2014/897428/