Submitted to: Journal of Food Safety
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 31, 2001
Publication Date: N/A
Interpretive Summary: Soy protein concentrate (SPC), an antioxidant and extender, is a common ingredient in ready-to-eat (RTE) meats. The ionizing radiation dose required to inactivate 99.999% of L. monocytogenes was 3.25 kGy in bologna without SPC but 3.70 kGy for bologna containing 3.5 percent SPC. SPC did not prevent radiation induced lipid oxidation, but did help maintain bologna color as a result of irradiation. This work will help meat processors provide safer and more visually acceptable RTE meat products to consumers.
Technical Abstract: Soy protein concentrate (SPC), an extender and antioxidant, is a common additive in ready-to-eat meat products. When Listeria monocytogenes was inoculated into cooked beef bologna emulsion containing 0%, 1.75%, or 3.5% SPC the D-10 values were 0.66, 0.68, and 0.71kGy, respectively. Soluble antioxidant power, as determined by Ferric Reducing Antioxidant Power (FRAP) assay was 1958, 3572, and 5494 micromole in emulsion containing 0, 1.75% and 3.5% SPC, respectively. Soluble antioxidant power was not affected by ionizing radiation. The increased soluble antioxidant activity of SPC containing emulsion did not prevent ionizing radiation induced lipid oxidation as determined by TBARS assay. Hunter color analysis of both unirradiated and irradiated bologna slices containing SPC indicated decreased a-value as a result of irradiation, while the addition of SPC helped maintain b-value and L-value. The inclusion of SPC does not represent a barrier to ionizing radiation pasteurization of fine emulsion sausages for the parameters examined.