Selection of Lactobacillus strains to induce biological acidification in low acidity wines

• Two strains of Lactobacillus plantarum were selected to induce biological acidification in high pH grape must.
• Selected strains carried out the malolactic fermentation in grape must.
• Selected strains synthesize lactic acid from sugars fermentation to decrease the pH of wine.

Because of global warming, wines are obtained nowadays with high pH values and low acidity. This results in wines with disturbed flavor and increased susceptibility of microbial spoilage. The aim of this work was the selection of Lactobacillus strains with ability to induce biological acidification in low acidity grape musts to obtain more acidic wines. A screening of Lactobacillus strains was carried out using several selection criteria. Lactobacillus strains that grew in must, carried out the malolactic fermentation, acidified grape must, synthesized lactic acid from sugars, and showed high resistance to lysozyme and sulfur dioxide were selected. Selected strains were characterized based on their metabolism in grape must and their ability to synthesize biogenic amines.