ANTIMICROBIAL ACTION OF CHITOSAN AGAINST LACTIC-ACID BACTERIA SEPARATED FROM PICKLES

For the preservation of ''Asazuke'' (nonfermented pickles of cucumber) , antimicrobial action of chitosan against lactic acid bacteria isolat ed from deteriorated pickles was investigated. Appearance of turbidity in the liquid part of pickles during storage was caused by growth of lactic acid bacteria, in which Lactobacillus sake and Leuconostoc mese nteroides were found. Almost all the bacteria died out by a treatment with 0.01% of chitosan solution dissolved in 1% acetic acid (pH 5.5) f or 60 minutes, but this bactericidal action was lowered in the coexist ence of salt, carrageenan, or sodium mono glutamate, respectively. Und er the similar conditions, 3% salt and pH 5.5, to Asazuke, the combine d use of 0.05% chitosan and 1% glycine, or 2% ethylalcohol was effecti ve in inhibition of the growth of these lactic acid bacteria.