Spoilage potential and sensory profile associated with bacteria isolated from cold-smoked salmon

Off-odours/flavours associated with cold-smoked salmon spoilage are due to the activity of microflora. This study evaluated the spoilage potential of nine bacterial groups (Shewanella putrefaciens, Brochothrix thermosphacta, Aeromonas spp., Lactobacillus alimentarius, Lactobacillus sake,Lactobacillus farciminis, Carnobacterium piscicola, Photobacterium phosphoreum and Serratia liquefaciens) isolated from cold-smoked salmon. Five different isolates from each group were inoculated into sterile cold-smoked salmon blocks, and chemical and sensory changes were studied after five weeks of storage in vacuum packs at 6 degreesC. Bacterial growth was monitored weekly during the storage period. A sensory profile was assigned to each group, Principal component analysis allowed some bacterial species to be characterised by a specific odour, and correspondence factorial analysis discriminated among the species according to their spoilage potential. The bacteria mainly responsible for spoilage were L. sake, L. farciminis and B. thermosphacta, which produced sulphurous, acidic and rancid off-odours respectively. Some strains of S. liquefaciens,produced rubbery, cheesy or acidic off-odours. Some P. phosphoreum isolates were characterised by an acidic effect. (C) 2001 Elsevier Science Ltd. All rights reserved.