TYPES AND POPULATIONS OF MICROORGANISMS IN THE AIR OF FLUID MILK PLANTS

Abstract

Airborne viable particle counts in the milk processing areas of 10 dairy plants averaged 14 molds and 32 non-molds/10 liters. The bacteria isolated were primarily micrococci, Gram-negative rods (excluding coliform), bacilli, and coryne-bacteria. Twenty-five per cent of the isolates grew at 10 C in 5 days. These were principally bacilli and Gram-negative rods (excluding coliform). There was no apparent relationship between airborne microbial populations and keeping quality of the packaged milk.