Submitted to: Innovative Food Science and Emerging Technologies
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/28/2005
Publication Date: 7/1/2006
Citation: Juneja, V.K., Fan, X., Pena-Ramos, A., Diaz, M., Pacheco-Aguilar, R. 2006. The effect of grapefruit extract and temperature abuse on growth of clostridium perfringens from spore inocula in marinated, sous-vide chicken products. Innovative Food Science and Emerging Technologies. 7:100-106. Interpretive Summary: Commercial application of sous-vide (cook-in-bag) technology has been limited. Concerns have been expressed about the public-health risks associated with sous-vide processed foods because the mild heat treatment required to retain the sensory attributes may not ensure proper destruction of pathogenic and spoilage organisms. The safety of sous-vide foods cannot be considered to rely on only one single 'chilled storage' factor. Since one of the most common types of food poisoning in the United States is caused by the bacterium, Clostridium perfringens, there was a need to determine the fate of the pathogen in sous vide processed foods. We determined that marinated chicken breast meat supplemented with 100 or 200 ppm of grapefruit extract can provide an extra degree of safety in temperature abused products. These findings will be of immediate use to the retail food service operations and regulatory agencies to ensure the safety of the sous-vide foods.
Technical Abstract: Clostridium perfringens growth from a spore inoculum was investigated in vacuum-packaged, cook-in-bag, marinated chicken breast that included additional 1.0% NaCl. The packages were processed to an internal temperature of 71.1 deg C, ice chilled and stored at various temperatures. The total C. perfringens population was determined by plating diluted samples on tryptose-sulfite-cycloserine agar followed by anaerobic incubation for 48 h at 37 deg C. At 25 deg C, 100 or 200 ppm Citricidal (a grapefruit extract) was effective in delaying growth for 9 h. At 19 deg C, growth occurred within 13 h in all samples, regardless of the presence or absence of Citricidal. Supplementing marinated chicken products with Citricidal and the temperature abuses had no consistent effect on color, shear force or lipid oxidation. However, the organism may grow to unsafe levels if sous vide products are poorly handled or temperature abused for a relatively long period. An extra degree of safety may be assured in such products by supplementation with 100 or 200 ppm Citricidal.