Identities of the Pseudomonas spp. in flora from chilled chicken

Nine broilers from each of two different broiler farms were collected at th e slaughterhouse. Microbiological samples were collected from broiler chick en carcasses which were stored aerobically at 3+/-0.5 degrees C for 0, 3 or 8 days. By characterizing 40 colonies per broiler it was possible to evalu ate the shift in psychrotrophic bacteria on the skin during cold storage. M ost of these bacteria belong to the pseudomonads. The Shewan scheme was use d in order to distinguish between four groups of pseudomonads. On fresh pou ltry group II pseudomonads were most abundantly represented, followed by gr oup IV: group I and III strains were present in lower amounts. Non-fluoresc ing group II pseudomonads always predominated as spoilage became obvious (d ay 8). By including 36 reference strains, numerical analysis based on the s imple matching coefficient was performed on 180 representatively selected s trains. This revealed that Pseudomonas species indeed predominated when spo ilage was obvious. Non-fluorescing species were identified mainly as P. fra gi, but also as other strains belonging to P. fluorescens biovars A, B, C a nd F, P. lundensis and cluster 7 strains (unidentified). Microorganisms alr eady substantially present on the fresh poultry were found in the highest n umbers at the time of spoilage. (C) 1999 Elsevier Science B.V. All rights r eserved.