FUNGI IN FOODS

Abstract

Yeast and mold counts were compared on Potato Dextrose Agar using six acidulants and an antibiotic combination for controlling bacteria. Counts on the acidified media ranged from 61 to 82% of those obtained on the antibiotic medium. The acids in order of decreasing recovery of fungi were lactic, tartaric, citric, hydrochloric, sulfuric, and phosphoric. Both gram-negative and gram-positive bacteria produced countable colonies on acidified media at a pH of 3.5. No bacteria grew on the antibiotic medium. Recovery of stored yeast cells also was conducted, and it was possible to demonstrate a population of cells which would not initiate growth at a pH of 3.5.