Slime Formation on Cottage Cheese

Abstract

The effect of the storage temp. on the rate of slime formation on cottage cheese was detd., using 9 different cultures of bacteria capable of causing the defect. Some cultures failed to produce slime at 4.4[degree] or 10[degree]C. in 14 days, while others produced it in 7-11 days at 4.4[degree]C, and 5-7 days at 10[degree]. All cultures produced slime on cottage cheese held at 21[degree]C. in 1-4 days. Cottage cheese with a pH of 4.7 readily developed slime when the temp. was favorable. The bacteria capable of forming slime were destroyed by exposure to 62.8[degree]C. for 2.5 min. Of 15 cultures tested for chlorine resistance, 7 survived a 1-min. exposure to 5 ppm. Cl, 3 survived a 1-min. exposure to 25 ppm. and 2 survived a 1-min. exposure to 50 ppm.Cl. None of the cultures survived a 45_sec. exposure to 100 ppm. Cl. Cultures capable of forming slime on cottage cheese belonged to the following genera: Proteus, Pseudomonas, Aerobacter, Alcaligenes, and Achromobacter.