100 random samples of cheese, butter and ice-cream were collected from Assiut City markets for enumeration and isolation of psychrotrophic bacteria.
The mean psychrotrophic counts were 1.4x10°, 32.1x10°, 26x10°, 8.3x10
and 30.3x10° in damietta cheese, kareish cheese, hard cheese, ice cream and butter respectively. The bacterial genera most commonly found to contain psychrotrophic species are Pseudomonas, Flavobacter ium, Alcaligenes, Acinetobacter, Serratia, Proteus and Coliforms.
Deep freezing is highly recommended for storage of butter than refriger ator as it prolongs the keeping quality of butter.