Shelf-life of coleslaw made from cabbage treated with gaseous acetic acid

Coleslaw containing 25% mayonnaise was formulated with untreated cabbage (control) and cabbage fumigated with two levels of gaseous acetic acid: 0.08 mL and 0.50 mL/100 g cabbage. A device consisting of a rotating barrel and vaporizing chamber was used to fumigate the shredded cabbage. Populations of aerobic microorganisms in coleslaw made from untreated cabbage reached 10(8) cfu/g after 15 days in storage at 5C. Growth of lactic acid bacteria was extensive and in some cases this group was chiefly responsible for spoilage. Microorganisms were not detected in coleslaw made from cabbage fumigated at higher levels of acetic acid during 22 days in storage. Mayonnaise had a lethal effect on the microflora of cabbage, and fumigation with acetic acid prior to formulation of coleslaw increased the effect. The color of coleslaw was not affected by fumigation but CO2 production during storage was reduced.