PRESENCE AND COINCIDENCE OF LISTERIA SPP, MOTILE AEROMONADS AND YERSINIA-ENTEROCOLITICA IN A COLD-SMOKED SALMON PROCESSING AND PACKING PLANT

Environmental samples and samples of partially processed fish from a c old-smoked salmon processing and packing plant, and product samples pu rchased from retail outlets, were examined for the presence of Listeri a monocytogenes and other Listeria spp., motile aeromonads and Yersini a enterocolitica. Listeria spp. were not isolated from raw fish but we re a contaminant of processed and partially processed fish. Listeria s pp. were also detected in 18.8% of surfaces in contact with fish. Unli ke Listeria spp., motile aeromonads were isolated from the raw fish bu t not from the finished product. They were more frequently isolated fr om environmental sources than Listeria spp. Yersinia enterocolitica wa s not isolated from any of the samples tested. Little evidence was fou nd to show a coincidence of motile aeromonads and Listeria spp., since only one subset of samples showed such a link. It is concluded that c ontamination by Listeria spp. was from environmental sources at the pr ocessing plant at, or beyond, the slicing stage. Reducing the number o f wet areas and special cleaning and sanitation considerations for a c ontaminated site (the freezer seal) are suggested as ways of reducing contamination of the product.