Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/21/2004
Publication Date: 9/1/2003
Citation: Juneja, V.K., Sabah, J.R., Fung, D.Y. 2003. Effect of spices and organic acids on the growth of clostridium perfringens from spore incoula during cooling of sous-vide cooked ground beef products. Journal of Food Protection. 67(9):1840-1847. 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 in retail food service operations. Thus, there was a need to determine the cooling time and temperature for cooked meat products to remain pathogen-free and provide vital data for performing risk assessment on cooked meat. We found that incorporation of spices in roast beef will not ensure the safety of cooked products, if the rate and extent of cooling is not adequate. However, sodium lactate in beef will prevent growth of C. perfringens during cooling, thereby meeting the required USDA stabilization standard of not more than ten times increase of this food poisoning bacterium. These findings will be of immediate use to the retail food service operations and regulatory agencies to ensure the safety of the cooked foods.
Technical Abstract: This study was conducted to evaluate the effect of organic acids and spices, alone or combined, on Clostridium perfringens growth in cooked ground beef products during alternative cooling procedures. Ground beef was inoculated with a three-strain cocktail of C. perfringens (ATCC 10388, NCTC 8238, and NCTC 8239) at 2-log10 spore/g and prepared following an industrial recipe (10% water, 1.5% sodium chloride, and 0.5% sodium tri-phosphate (w/w)). Treatments consisted in the base meat plus combinations of commercial solutions of sodium lactate or sodium citrate (0% or 2% w/w) to chilli, garlic and herbs, curry, oregano, or clove in commercial powder form (0% or 1% w/w). Untreated meat was used as the control. Vacuum-packaged samples of each treatment were cooked (75°C for 20 min) and cooled from 54.4°C to 7.2°C in 15, 18, or 21 h. Spore counts were taken after inoculation, cooking, and cooling. All treatments containing sodium citrate reduced the population of C. perfringens by about 0.38 to 1.14 log10 during each of the three cooling procedures. No sodium citrate and spice combinations showed antagonisms or synergisms. Regardless of the cooling time, any of the five spices alone or the control resulted in growth of C. perfringens above the required USDA stabilization standard of 1 log10. Except during the 21 h cooling, addition of sodium lactate prevented C. perfringens growth over 1 log10 unit. Depending on the cooling time and the spice, combinations of sodium lactate and a spice gave different results regarding C.perfringens growth within USDA limit of 1 log10 unit.