CONTROLLED PRODUCTION OF CIDER BY INDUCTION OF ALCOHOLIC FERMENTATIONAND MALOLACTIC CONVERSION

Characterization experiments involving lactic bacteria allowed a strai n of Leuconostoc oenos to be selected in terms of growth capacity at v ariable pH. temperature, ethanol and sulphite concentrations, malic to lactic conversion yield. acetic acid uptake and dextran production ca pacity. Cider was produced under controlled conditions where the effec t of Kloeckera apiculata yeasts on the development of Saccharomyces ce revisiae and production of major non-volatile compounds influencing en d product quality was studied. The apiculate yeast was found to produc e large amounts of acetic acid and use the other organic acids; also, it hindered fermentation to a certain extent. A study of the effect of the inoculation time with L. oenos as an inducer of malolactic fermen tation revealed sequential inoculation of the lactic bacterium once mo st major sugars in the must had been depleted to be the most favourabl e. Using yeast cell walls boosted fermentation development, as well as degradation of melic acid and synthesis of succinic and acetic acid.