title: Effects of salt, sodium pyrophosphate, and sodium lactate on the probability of growth of Escherichia coli O157:H7 in ground beef.
abstract: Ground beef products are susceptible to contamination with Escherichia coli O157:H7. The objective of this study was to examine the effect of salt, sodium pyrophosphate (SPP), and sodium lactate on the probability of growth of E. coli O157:H7 in ground beef under a temperature abuse condition. Ground beef containing 0 to 2.25% salt, 0 to 0.5% SPP, and 0 to 3% lactate was inoculated with a four-strain mixture of E. coli O157:H7, vacuum packaged, and stored at 10°C for 15 days. A total of 25 combinations of the three additives, each with 20 samples, were tested. A logistic regression was used to model the probability of growth of E. coli O157:H7 (with a 1.0-log CFU/g increase during storage) as a function of salt, SPP, and lactate. The resultant probability model indicated that lactate at higher concentrations decreased the probability of growth of E. coli O157:H7 in ground beef, and the effect was more pronounced at higher salt concentrations. At salt concentrations below 1.3%, the increase of SPP concentration marginally increased the growth probabilities of E. coli O157:H7. The model illustrated the effect of salt, SPP, and lactate on the growth probabilities and growth or no-growth behavior of E. coli O157:H7 in ground beef and can be used to improve the microbial food safety of ground beef products.
authors.affiliation: Residue Chemistry and Microbial Food Safety Research Unit, Eastern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19038, USA. andy.hwang@ars.usda.gov
authors.forename: Cheng-An
authors.initials: CA
authors.lastname: Hwang
authors.forename: Vijay
authors.initials: V
authors.lastname: Juneja
mesh_terms: D000818:Animals; D002417:Cattle; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D011756:Diphosphates / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D019453:Escherichia coli O157 / Q000187:drug effects* / Q000254:growth & development; D005506:Food Contamination / Q000032:analysis / Q000517:prevention & control; D005519:Food Preservation / Q000379:methods*; D005520:Food Preservatives / Q000494:pharmacology*; D006801:Humans; D008461:Meat Products / Q000382:microbiology*; D019354:Sodium Lactate / Q000494:pharmacology*; D013696:Temperature
chemical_list: D011756:Diphosphates; D005520:Food Preservatives; C003319:sodium pyrophosphate; D019354:Sodium Lactate