MICROBIAL-POPULATIONS ASSOCIATED WITH REFRIGERATED POULTRY

Predominant microbial spoilage populations associated with the skin of refrigerated poultry were enumerated and characterized on 24 fresh bi rds, sampled immediately after air chilling and packaging, and 48 micr obiologically spoiled birds, from a South African processing plant. To tal aerobic plate counts, cram-negative counts, lactic acid bacteria c ounts and yeast counts were determined, and the incidence of Salmonell a investigated The highest microbial numbers were consistently obtaine d for total aerobic plate counts, followed by Gram-negative, lactic ac id bacteria and yeast counts, in decreasing order Characterization of 139 predominant bacterial isolates from total aerobic plate counts of fresh birds indicated the presence of Enterobacteriaceae (30.2%), Micr ococcus (18.6%) and the fluorescent Pseudomonas group (13.9%). On spoi led birds, Enterobacteriaceae (29.2%) and the fluorescent Pseudomonas (21.8%) and Aeromonas/Vibrio (15.6%) groups predominated. The microflo ra (139 isolates) responsible for Gram-negative counts of fresh carcas ses was dominated by the Aeromonas/Vibrio group (65.1%), Enterobacteri aceae (16.4%) and the non-fluorescent Pseudomonas group (11.6%). Gram- negative bacterial isolates of spoiled carcasses were dominated by the fluorescent Pseudomonas (32.3%), Aeromonas/Vibrio (29.2%) and non-flu orescent Pseudomonas (24.0%) groups as well as Enterobacteriaceae (10. 4%). Predominant lactic acid bacteria were pediococci (89.3%) on fresh birds and homofermentative lactobacilli (81.6%) on spoiled carcasses. Salmonella serotypes Blockley, Reading and Schwarzengrund were isolat ed from fresh and spoiled carcasses.