RESISTANCE OF FOOD SPOILAGE YEASTS TO SORBIC ACID

About 100 strains isolated from spoiled foods and beverages were screened for their ability to grow in the presence of successively higher concentrations of sorbic acid. Most strains were able to grow at 150 ppm, 40% at 500 ppm and remarkably two strains of Zygosaccharomyces bailii tolerated 800 ppm. Significant differences were observed between strains of the same species. A general observation was that increasing concentration of sorbic acid resulted in a decrease in the biomass present at the stationary phase and increase in the duration of the lag phase.