AIR-BORNE MICROORGANISM POPULATIONS IN FOOD PACKAGING AREAS1,2

Abstract

Summary A slit air-sampler was used to ascertain the numbers of air-borne bacteria, yeasts and molds in dairy product packaging areas. The mean air-borne bacteria count for all food packaging areas investigated was below 6 per ft3. The highest mean count for a daily sampling period was just over 10 per ft3. The mean count for air-borne yeasts was 2 per ft3 for all samples collected. About 17% of all counts were less than 1 yeast per 5 ft3. The mean air-borne mold count for all samples was over 12 per ft3 with nearly 10% of the counts over 20 per ft3. A mean count in cottage cheese packaging was over 22 mold per ft3 while mean counts for individual sampling days revealed populations as high as 67 mold per ft3. There were significant day to day variations in all areas and standard deviations of daily sampling periods indicated significant variations within 4-hr test periods. Some degree of correlation between worker activity and air-borne counts was indicated by the results. However, it is evident that other factors also contribute to the air-borne population.