Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: 9/27/2007
Publication Date: 10/20/2007
Citation: Juneja, V.K., Bari, M., Inatsu, Y., Kawamoto, S. 2007. Control of Clostridium perfringens spores by plant-derived antimicrobials during cooling of cooked ground beef. Meeting Abstract. P.26. Interpretive Summary:
Technical Abstract: Inhibition of Clostridium perfringens spore germination and outgrowth by carvacrol, cinnamaldehyde, thymol, oregano oil and two green tea extracts with low (green tea leaf powder (GTL); 141 mg of total catechins/g of green tea extract) and high (green tea leaf extract (GTE); 697 mg of total catechins/g of extract) catechin levels was evaluated during abusive chilling of cooked ground beef (75% lean). Test substances were mixed into thawed ground beef at concentrations of 0.1, 0.5, 1.0 or 2.0% (w/w) along with a heat-activated three-strain C. perfringens spore cocktail to obtain final spore concentrations of ca. 2.8 log spores/g. Aliquots (5 g) of the ground beef mixtures were vacuum-packaged and then cooked in a water bath, the temperature of which was raised to 60C in 1 h. Thereafter, the products were cooled from 54.4C to 7.2C in 12, 15, 18 or 21 h, resulting in significant increases (p less than 0.05) in the germination and outgrowth of C. perfringens populations in the ground beef without added test compounds. Cinnamaldehyde was significantly (p less than 0.05) more effective (less than 1.0 log CFU/g growth) at a lower concentration (0.5%) at the most abusive chilling rate evaluated (21 h) than the other compounds (carvacrol, thymol, oregano oil). Supplementation with 0.5 to 2% levels of GTL did not inhibit C. perfringens growth from spores. In contrast, the addition of 0.5 to 2% levels of GTE to beef resulted in a concentration- and time-dependent inhibition of C. perfringens growth from spores. At a 2% level of GTE, a significant (p less than 0.05) inhibition of growth occurred at all chill rates for cooked ground beef. These results suggest that incorporation of lower levels of the test compounds with other antimicrobials used in meat product formulations can reduce the potential risk of C. perfringens germination and outgrowth during abusive cooling regimes.