Microbiological composition of raw milk from selected farms in the Camembert region of Normandy.

Abstract

Raw milk from 27 farms was sampled over 6 months for listerias, salmonellas, Yersinia enterocolitica and campylobacters. Total bacterial counts and somatic cell counts were measured. Lactococci, lactobacilli, dextran-producing leuconostocs, Brevibacterium linens, yeasts and moulds, Staphylococcus aureus and other Micrococcaceae, Pseudomonas, coliforms, Escherichia coli, enterococci, Clostridium perfringens and spores of anaerobic lactate-fermenting bacteria were also counted. Pseudomonas (2000 cfu ml-1), lactococci (760 cfu ml-1) and Micrococcaceae (720 cfu ml-1) were the most numerous groups. Lactic acid bacteria were detected in all samples. Coliforms were present in most samples, but 84% of samples had counts < 100 cfu ml-1. Staphylococcus aureus was detected in 62% of milks, the average count was 410 cfu ml-1. About 80% of supplies had < or = 10 E. coli cfu ml-1 and all samples had < or = 1 Cl. perfringens cfu ml-1. Two of the tested milks were positive for salmonellas (2.9%), four were positive for Listeria monocytogenes (5.8%), 25 for Yersinia enterocolitica (36%) and one for campylobacters (1.4%).