[Enterobacteriaceae as indicators of the presence of Salmonella and the hygienic conditions of meat and bone meals].

The purpose of this study was to establish the relationship between Enterobacteriaceae counts and the presence of Salmonella in meat-and-bone meals. Ninety meat-and-bone meal sample units (9 lots) from five producing plants from the Greater Buenos Aires, Argentina, were analyzed. The presence of Salmonella was detected through pre-enrichment of the samples followed by selective enrichment in two broth cultures and isolations after 24 and 48 hours. For Enterobacteriaceae counts the recovery of sublethally injured cells was carried out for two hours on trypticase soy agar, followed by the addition of selective agar. The overall Enterobacteriaceae count for the 90 sample units was 3.0. Seven (77.7%) of the 9 lots were positive for Salmonella. The correlation coefficient between Enterobacteriaceae counts and Salmonella was 0.81 with a confidence limit (95%) of 0.35-0.95. The results of this study indicate that Enterobacteriaceae counts are not good indicators of the presence of Salmonella in meat-and-bone meals. However, they could be used to assess their hygienic quality.