Malolactic fermentation induced by Lactobacillus plantarum in Malbec wines from Argentina

M.C. LERENA; M.C. ROJO; S. SARI; L.A. MERCADO; S. KRIEGER-WEBER; M. COMBINA

SOUTH AFRICAN JOURNAL OF ENOLOGY AND VITICULTURE

SOUTH AFRICAN SOC ENOLOGY & VITICULTURE-SASEV

Año: 2016

0253-939X

The current market requirements to obtain wines with enhanced complexity and varietal character propose the finding of new microorganisms capable to drive the malolactic fermentation (MLF) and to contribute to new and distinctive sensory profiles of the wines. During MLF malic acid naturally present in must is converted into lactic acid by a decarboxylation reaction driven by lactic acid bacteria. Recently, a new strain of Lactobacillus plantarum suitable for MLF in high pH wines has been selected. This study evaluates the capacity of L. plantarum V22 starter culture to complete MLF at laboratory and semi-industrial scale in different Malbec musts from Argentina. Malbec musts were co-inoculated with S. cerevisiae D254 and L. plantarum V22 to conduct alcoholic fermentation and MLF respectively. Two groups of Malbec musts were identified according to the ability of L. plantarum to consume malic acid. A first group called ?High Feasibity for MLF? characterized by high viability of L. plantarum and the completion of MLF. On the other hand, a second group termed as ?Partial Feasibility for MLF? was identified, characterized by a decreased viability of L. plantarum and incomplete MLF. This study shows that the capacity of L. plantarum to conduct MLF in Malbec musts is dependent on must composition, further suggesting that the pH evolution during the fermentation process, rather than initial pH, would be a critical factor affecting the successful completion of MLF.