Growth and survival of E. coli O157:H7 during the manufacture and ripening of a smear-ripened cheese produced from raw milk

M.M. MAHER, K.N. JORDAN, M.E. UPTON AND A. COFFEY. 2001. Aims: The behaviour of Escherichia coli O157:H7 was studied during the manufacture and ripening of a smear-ripened cheese produced from raw milk. Methods and Results: Cheese was manufactured on a laboratory scale using milk (20 l) inoculated with E. coli O157:H7, and enumeration was carried out using CT-SMAC. From an initial level of 1·52 ± 0·03 log cfu ml–1 in the milk (34 ± 2 cfu ml–1), the numbers increased to 3·4 ± 0·05 log cfu g–1 in the cheese at day 1. During ripening, the numbers decreased to