Ecology of indigenous lactic acid bacteria along different winemaking processes of Tempranillo red wine from La Rioja (Spain).

Carmen Tenorio,Rosa López,Lucía González-Arenzana,Pilar Santamaría,Isabel López-Alfaro

doi:10.1100/2012/796327

Abstract

Ecology of the lactic acid bacteria (LAB) during alcoholic fermentation (AF) and spontaneous malolactic fermentation (MLF) of Tempranillo wines from four wineries of La Rioja has been studied analyzing the influence of the winemaking method, processing conditions, and geographical origin. Five different LAB species were isolated during AF, while, during MLF, only Oenococcus oeni was detected. Although the clonal diversity of O. oeni strains was moderate, mixed populations were observed, becoming at least one strain with distinct PFGE profile the main responsible for MLF. Neither the winemaking method nor the cellar situation was correlated with the LAB diversity. However, processing conditions influenced the total number of isolates and the percentage of each isolated species and strains. The winemaking method could cause that genotypes found in semicarbonic maceration did not appear in other wineries. Four genotypes of O. oeni were isolated in more than one of the rest wineries. These four together with other dominant strains might be included in a future selection process.

Highlights

Winemaking is defined like the operations and the practises carried out to transform the grapes in wine [1]
The malolactic fermentation (MLF) is not a real fermentation, it mainly consists in a transformation of Lmalic acid into L-lactic acid and carbon dioxide, as a part of the lactic acid bacteria (LAB) metabolism [2], and it contributes to improve the stability and the quality of the final wine [3,4,5]
Oenococcus oeni is the best adapted LAB species to the stressful environment in wine [6, 7] so it is the species which is mostly isolated at this stage [8], being the main responsible for the development of MLF and the most interesting to be selected [9]

Summary

Introduction

Winemaking is defined like the operations and the practises carried out to transform the grapes in wine [1] This includes two fermentative stages, which are the alcoholic fermentation (AF) led by yeast and the malolactic fermentation (MLF) performed by lactic acid bacteria (LAB). In order to get a better control of MLF and to avoid wine spoilage [10, 11], wineries have started to employ commercial cultures from selected O. oeni strains. Not always these malolactic starters are successfully implanted [12]. More relevant correlations between LAB diversity and winemaking process were investigated

Objectives

Methods

Results