Submitted to: Food Microbiology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 3/14/2013
Publication Date: 5/8/2013
Citation: Redondo-Solano, M., Valenzuela-Martinez, C., Cassada, D., Snow, D.D., Burson, D.E., Juneja, V.K., Thippareddi, H. 2013. Effect of meat ingredients (sodium nitrite and erythorbate) and processing (vacuum storage and packaging atmosphere) on germination and outgrowth of Clostridium perfringens spores in ham during abusive cooling . Food Microbiology. 35:108-115. Interpretive Summary: C. perfringens is one of the most common causes of food poisoning in the United States. Illnesses have been traditionally associated with slow cooling or inadequate reheating of cooked products in food service establishments. Thus, there was a need to determine the time and temperature for cooked meat products to remain pathogen-free. We determined that the meat processing conditions such as product formulation and preparation procedures (such as length of refrigerated storage) can affect C. perfringens spore germination and outgrowth. These findings will be of immediate use to the food industry and regulatory agencies to ensure the safety of the cooked foods.
Technical Abstract: The effect of nitrite and erythorbate on Clostridium perfringens spore germination and outgrowth in ham during abusive cooling (15 h) was evaluated. Ham was formulated with ground pork, NaNO2 (0, 50, 100, 150 or 200 ppm) and sodium erythorbate (0 or 547 ppm). Ten grams of meat (stored at 5C for 3 or 24 h after preparation) were transferred to a vacuum bag and inoculated with a three-strain C. perfringens spore cocktail to obtain an inoculum of ca. 2.5 log spores/g. The bags were vacuum-sealed, and the meat was heat treated (75C, 20 min) and cooled within 15 h from 54.4 to 4.4C. Residual nitrite was determined before and after heat treatment using ion chromatography with colorimetric detection. Cooling of ham (control) stored for 3 and 24 h, resulted in C. perfringens population increases of 1.46 and 4.20 log CFU/g, respectively. For samples that contained low NaNO2 concentrations and were stored for 3 h, C. perfringens populations of 5.22 and 2.83 log CFU/g were observed with or without sodium erythorbate, respectively. Residual nitrite was stable for both storage times. Meat processing ingredients (sodium nitrite and sodium erythorbate) and their concentrations, and storage time subsequent to preparation of meat (oxygen content) affect C. perfringens spore germination and outgrowth during abusive cooling of ham.