Development of decontamination procedures for beef trimmings

Abstract

Beef trimmings of 73/27 or 50/50 lean and fat content were obtained from a commercial plant. The trimmings were randomly assigned to four treatments: control, 4% lactic acid (LA), 4% lactic acid plus hot water (LA+HW), and 4% lactic acid plus 10% trisodium phosphate plus hot water (LA+TSP+HW). Meat color was evaluated on both the trimmings before and after treatment and on the ground beef chubs on days 0, 7, 14, 21, and 28 of storage. The L*, a*, and b* color space values were determined to measure objective color, and a trained color panel was used to measure subjective color. After treatment, the lean color of all trimming types was darker or grayer in the LA+HW or LA+TSP+HW treated trimmings. Lean color of the ground beef was not noticeably darker due to treatment after grinding, but the LA treatment resulted in visually darker ground beef especially with subsequent storage time. A trained descriptive attribute panel evaluated flavor quality characteristics of the ground beef patties on each storage day. The LA treated patties had slightly lower levels of cooked beef/brothy, cooked beef fat, and grainy flavors. Sample pH, TBA values, aerobic plate counts (APCs) and fat and moisture values also were measured. Total APCs were measured on the excised sample after treatment and on the ground samples on each storage day. The LA+HW and LA+TSP+HW treatments reduced the surface APCs of the trimmings by 1 log₁₀CFU/cm². However, treating beef trimming with lactic acid reduced the APCs of the ground beef by 1.3 log₁₀CFU/g and had significantly lower APCs on days 7, 14, and 21 compared to the control and other treatments. These treatments, especially the LA+HW would be an acceptable intervention step to be further examined to assist in the decontamination of beef trimmings without adversely effecting ground beef shelf-life and flavor attributes.