ARS | Publication request: Kinetics of thermal destruction of Salmonella in ground chicken by containing trans-cinnamaldehyde and carvacrol

Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 19, 2011
Publication Date: January 1, 2012
Citation: Juneja, V.K., Yadav, A.S., Hwang, C., Sheen, S., Mukhopadhyay, S., Friedman, M. 2012. Kinetics of thermal destruction of Salmonella in ground chicken by containing trans-cinnamaldehyde and carvacrol. Journal of Food Protection. 75(2):289-296.

Interpretive Summary: Undercooked meat and poultry products are commonly implicated as transmission vehicles in Salmonella outbreaks of foodborne illness. This emphasizes the need to better define and quantify the heat treatment given to these foods to provide an adequate degree of protection against survival of Salmonella. We determined that a heat treatment at 60C for 37.8 min would kill more than one million bacteria in chicken. The heating time can be reduced more than 2 fold if chicken is supplemented with 1% carvacrol or cinnamaldehyde. We developed a mathematical model for predicting the destruction of this pathogen in chicken. The model can be used to predict the time required at any temperature to kill a certain number of bacteria. This information will be of immediate use to consumers and to the food industry and regulatory agencies to aid in the development of guidelines to ensure safety of the food supply.

Technical Abstract: We investigated the heat resistance of an eight strain cocktail of Salmonella spp. in chicken supplemented with cinnamaldehyde (0 – 1.0%, w/w) and carvacrol (0 – 1.0%, w/w). Inoculated meat was packaged in bags which were completely immersed in a circulating water bath and held at 55 to 71C for predetermined lengths of time. The recovery medium was tryptic soy agar supplemented with 0.6% yeast extract and 1% sodium pyruvate. D-values, determined by linear regression, in chicken were 17.45, 2.89, 0.75 and 0.29 min at 55, 60, 65 and 71C, respectively (z = 9.02C). Using a survival model for non-linear survival curves, D-values in chicken ranged from 13.52 min (D1; major population) and 51.99 min (D2; heat-resistant sub-population) at 55C to 0.15 min (D1) and 1.49 min (D2) at 71C. When Salmonella cocktail was heated in chicken supplemented with 0.1 – 1.0% cinnamaldehyde or carvacrol, D-values calculated by both approaches were consistently less at all temperatures. This observation suggests that the added natural antimicrobials in chicken render Salmonella spp. more sensitive to the lethal effect of heat. Thermal death times from this study will be beneficial to the food industry in designing HACCP plans to effectively eliminate Salmonella spp. in chicken products used in this study.