Enterotoxin production in milk at 22 and 4°C by Escherichia coli and Yersinia enterocolitica

Abstract

Enterotoxigenic Escherichia coli (5 strains) and Yersinia enterocolitica (5 strains) were cultivated in sterile milk at 22 and 4°C. The bacteria grew well at both temperatures. Three strains of E. coli produced heat-labile enterotoxin in the milk at 22°C as demonstrated by enzyme-linked immunosorbent assay. Heat-stable enterotoxins were not detected in the milk by the infant mouse test.