The incidence and level of contamination of British fresh sausages and ingredients with salmonellas

Abstract

SUMMARYA five-tube most probable number (MPN) method, with pre-enrichment and enrichment stages, was used in a study of the incidence of salmonella contamination of British fresh sausages and the ingredients used in their manufacture. All samples were taken from a large factory in the course of routine production. There was an incidence of 65 % contamination of pork (n= 20) and 55% (n= 20) in pork and beef sausages. The incidences of contamination of uncooked ingredients varied from 95 % for mechanically recovered meat (n= 20) to 10 % for another type of meat. Cooked and/or dried ingredients were rarely contaminated with these organisms and, when contamination occurred, coliforms were also important.The numbers of salmonellas isolated ranged from 7–40 for pork sausages, from 8–24 for beef and pork sausages and from 0·8–378 organisms/g for ingredients.The following salmonella serotypes were isolated (ranked in descending order of incidence):S. derby, S. dublin, S. newport, S. stanley, S. typhimurium, S. heidelberg, S. infantisandS. agona.