Airborne Listeria spp. in the red meat processing industry

Abstract

The aim of this study was to determine the potential presence of the airborne Listeria spp. and its correlation with the aerobic mesophilic bacteria and Listeria carcass contamination in three red meat slaughtering and three processing plants. Airborne L. seeligeri and L. innocua were determined using 8 (5.06%, n = 158) air samples taken on the locations characteristic for aerosol generating and in a chilly environment. The positive airborne samples of Listeria spp. were in an insignificant (P > 0.05) relation with the highest airborne bacteria counts. On the carcass, only 1 positive case (0.69%, n = 144) of L. innocua was determined, presumably owing to the low airborne Listeria counts and its unpredictable settling rates. In addition, insignificant (P > 0.05) influences of air moisture and airflow on the airborne Listeria were found. Nevertheles, the methods currently used to determine the airborne Listeria and its relationships to aerosol viable mesophilic bacteria and carcass contamination need to be reconsidered in future investigations.