The use of alternative technologies to develop malolactic fermentation in wine

The development of the malolactic fermentation, bioconversion Of L-malic ac id to L-lactic acid, is a difficult and time-consuming process that does no t always proceed favorably under the natural conditions of wine. Traditiona l fermentations are used worldwide to produce high-quality wines, although delay or failure is not an unusual outcome. During recent years several tec hnologies have been proposed to induce biological deacidification of wines by using, malolactic bacteria, principally Oenococcus oeni and Lactobacillu s sp. These alternative technologies usually involve the use of high densit ies of cells or enzymes, free or immobilized onto different matrices. Immob ilization materials, several types of bioreactors, and the properties of ma ny specific systems are discussed in this review.