A probability model describing the interface between survival and death of Escherichia coli O157:H7 in a mayonnaise model system

摘要: Abstract A probability model was developed to describe the influence of temperature (10–30°C) and factors characterizing composition mayonnaise (salt [0·5–16·5%], pH [3·5–6·0], acetic acid [0–4%] sucrose [0–8%]) on survival Escherichia coli O157:H7 in tryptic soy broth. adjusted independently by use HCl or NaOH. Logistic polynomial regression with a total 1820 factor combinations used main, quadratic, cross-product effects environmental factors. The successfully predicted death 1772 (97·4%) samples; those incorrectly predicted, 28 were false-positive (survival where occurred) 20 false-negative (death occurred). concordance index 99·4% disconcordance 0·6%, indicating good fit observed data. validated using data from experimental inoculated E. O157:H7. Of 30 acid, salt tested, survival/death only six cases and, these, one prediction not ‘fail-safe’. This attributed quadratic model, attempts make predictions outside boundary conditions. results suggest that here can be usefully applied mayonnaise.