Effects of a unique application of electrical stimulation on tenderness, color, and quality attributes of the beef longissimus muscle

This study evaluated effects of four uniquely applied beef carcass electric al stimulation (ES) treatments on USDA grade factors, muscle color, subprim al purge loss, cooked steak weight loss, and cooked steak tenderness. One s ide of each (n = 284) beef carcass was subjected to ES using one of four tr eatments (medium voltage for medium duration, MVMD; medium voltage for long duration, MVLD; high voltage for medium duration, HVMD; or high voltage fo r long duration, HVLD) and was compared to its corresponding non-ES control side. Electrical stimulation of beef sides was applied focusing on middle meats while preventing severe contraction of the round and chuck. From matc hed (ES and control) sides of 120 carcasses (10 each of Select, low Choice, and upper two-thirds of Choice in each of the four ES treatments), longiss imus steaks (2.5 cru thick) were cooked and used for Warner-Bratzler shear force (WBS) analysis. Mean marbling scores (n = 284) for stimulated sides d id not differ (P = .923) from those for control sides within ES treatment c lasses. Mean values for CIE L*, a*, and b* of lean color (n = 284) were hig her (P < .05) for MVMD, MVLD, HVMD, and HVLD treated sides than for the res pective control sides. When WBS values for steaks were adjusted to an equal visual degree of doneness, WBS values (n = 120) were lower (P < .05) for E S treated sides than for control sides for all four types of ES application treatments. Treatment responses were not influenced by USDA Quality Grade group. For those carcasses for which the control sides had WBS values great er than 4.5 kg, matching sides treated with MVMD, MVLD, HVMD, or HVLD had W BS values less than 4.5 kg 50, 88, 60, and 75% of the time, respectively. M ean cooked steak weight loss (n = 120), adjusted Do an equal visual degree of doneness, and mean purge loss (n = 24) did not differ with ES treatment.