Encapsulated lactic acid bacteria for control of malolactic fermentation in wine.

Abstract

The kinetics of both malolactic fermentation in Chardonnay wine by encapsulating Lactobacillus casei cells in pectate gel and lyophilized Oenococcus oeni culture has been carried out. The influence of acidity, sulfur dioxide content, and organic acid content on the malolactic activity of the bacteria has been controlled. Encapsulated bacteria degraded 30%, of malic acid in white wine, deacidifying it from pH 3.15 to 3.40, whereas the lyophilized culture degraded 48% of malic acid, deacidifying from pH 3.15 to 3.60. The degree of conversion of malic acid in wine by the encapsulated cells was twice as high as that obtained by the free Lactobacillus casei cells. The operational stability of calcium pectate gel capsules was 6 months. It has been proved that the encapsulated biocatalyst increases the rate of fermentation, and induces the fermentation to take place at high ethanol concentrations. The proposed encapsulated biocatalyst is an attractive material for industrial applications in continuous winemaking processes.