Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/1/2006
Publication Date: 3/1/2007
Citation: Velugoti, P.R., Lalit, B.K., Juneja, V.K., Thippareddi, H. 2007. Inhibition of germination and outgrowth of clostridium perfringens spores by lactic acid salts during cooling of cooked ground turkey. Journal of Food Protection. 70:923-929. Interpretive Summary: One of the most common types of food poisoning in the United States is caused by the bacterium Clostridium perfringens. Illnesses have been traditionally associated with inadequate cooling practices of cooked meats in retail food service operations. Thus, there was a need to determine the cooling times and temperatures for cooked meat products to remain pathogen-free and to provide data for performing risk assessments on cooked meat. We determined that cooling times for marinated ground turkey breast products after heat processing can be extended to 21 h by incorporation of the antimicrobial ingredients sodium lactate, potassium lactate, or calcium lactate at more than or equal to 1.0% in the formulation to reduce the potential risk of C. perfringens germination and outgrowth. These findings will be of immediate use to retail food service operations and regulatory agencies to ensure the safety of cooked turkey products.
Technical Abstract: Inhibition of Clostridium perfringens spore germination and outgrowth by lactic acid salts during exponential cooling of cooked ground turkey products was evaluated. Injected turkey containing either calcium lactate, potassium lactate, or sodium lactate (1.0, 2.0, 3.0 or 4.8% w/w) along with a control (product without lactate) were inoculated with a three-strain cocktail of C. perfringens spores to achieve a final spore population of 2.5-3.0 log10 CFU/g. Inoculated product was heat treated (75 degree C/20 min) and exponentially cooled from 54.5 degree C to 7.2 degree C in either 21, 18, 15, 12, 9 or 6.5 h. Cooling of turkey (containing no antimicrobials) resulted in C. perfringens germination and outgrowth of 0.5, 2.4, 3.4, 5.1, 5.8 and 5.8 log10 CFU/g when exponentially cooled from 54.4 degree C to 7.2 degree C in 6.5,9,12,15,18, and 21 h, respectively. Incorporation of these antimicrobials (lactates), regardless of the type (Ca, Na or K salts), inhibited germination and outgrowth of C. perfringens spores at all the concentrations evaluated. Increasing concentrations of the antimicrobials resulted in greater inhibition of spore germination and outgrowth. In general, calcium lactate significantly (p less than 0.05%) was more effective in inhibiting the germination and outgrowth of C. perfringens spores at greater than or equal to 1.0% concentration compared to sodium and potassium lactates. Incorporation of these antimicrobials in cooked, ready-to-eat turkey products can provide additional protection in controlling germination and outgrowth of C. perfringens spores during cooling (stabilization).