Ground beef shelf life assessment as influenced by sodium lactate, sodium propionate, sodium diacetate, and soy protein concentrate

Abstract

In phase I all-beef and soy-added ground beef patties containing sodium lactate, sodium propionate, and sodium diacetate at various levels and combinations were stored for nine months at -10°C. Upon cooking, the addition of sodium lactate increased cooked beef/brothy, cooked beef/fat and soda flavor and decreased cardboard and soured flavors. Sodium diacetate increased soured flavor, sour basic taste and decreased the positive effects of sodium lactate on cardboard flavor. The addition of treatments intensified pepper flavor and salt basic taste. Control patties were less cohesive, drier, and softer than treated patties. The addition of soy to treated ground beef patties intensified cooked beef/fat flavor, salt basic taste, decreased cohesiveness and increased juiciness. The addition of sodium lactate alone and in combination with sodium propionate increased pH values, while the addition of sodium lactate with sodium diacetate resulted in pH values similar to the control. Treatment had only slight affects on TBA values. The color of ground beef patties was not affected by treatment, but treatments did decrease two-tone color over nine months of frozen storage when compared to controls. Soy-added patties, in general, were lower in positive-flavor notes associated with ground beef. However, after nine months of frozen storage soy-added and beef treatments did not differ in cooked beef/brothy and serum/bloody flavor attributes. Soy-added patties had lower negative flavor notes associated with lipid oxidation during frozen storage and lower TBA values. With increased storage, soy patties became brighter, cherry-red with slightly less two-toned color when compared to all-beef patties. In phase II patties from the same treatments as phase I were inoculated with a 10⁶ log10 CFU/g rifampicin-resistant strain of Escherichia coli 0157:H7 and Salmonella typhimurium and stored for 21 days at -10°C. Following frozen storage patties from each treatment were cooked to either 54°C or 71°C and total numbers of rifampicin-resistant E.coli 0157:H7 and S. typhimurium were determined. The addition of treatments or soy did not increase heat sensitivity of E. coli or S. typhimurium. Soy-added patties treated with sodium diacetate, sodium propionate and sodium diacetate increased cook yields.