Behavior of Enteropathogenic Escherichia coli in Camembert Cheese Made From Ultrafiltered Milk

ABSTRACT

Skimmilk retentates from ultrafiltration (UF) were used in combination with concentrated cream (67% milk fat) to prepare a liquid precheese mixture that with the addition of rennet, lactic starter culture and a mold spore preparation of Penicillium candidum was transformed readily into Camembert cheese upon ripening. Yield increases from the retention of soluble milk protein, closer weight control tolerances for individual cheeses and reduction in rennet in comparison to the conventional Camembert process were observed. The behavior of enteropathogenic E. coli (ECC) serotypes was demonstrated in the Camembert cheese made from UF processes. Relationships were determined in UF Camembert as to microbial type and numbers used to inoculate the precheese, and as to site of survival and growth of different EEC serotypes. Differences which were observed in the physicochemical properties between conventional and UF cheesemilk mixtures predisposed the UF Camembert cheeses to greater E. coli survival and growth than in the Camembert cheeses made conventionally.