Abstract:
Our objective was to determine the effects
of endpoint temperature, cooking method, and
marbling on Warner-Bratzler shear force (WBSF; an objective method for determining
tenderness) of three beef muscles. Eighteen
subprimals of a muscle containing low content
of connective tissue, longissimus lumborum
(strip loin), and two muscles containing a high content of connective tissue, biceps femoris (bottom round) and deep pectoralis (brisket), were selected from USDA Select and Choice (Certified Angus Beef) carcasses. After 14 days of aging, subprimals were frozen, fabricated into steaks, and stored frozen until cooking. Steaks were assigned to one of two cooking methods, the Magikitch’n® electric belt grill (a rapid conduction method) or a water bath (a slower, convection method); and one of nine endpoint cooking temperatures, 104, 113, 122, 131, 140, 149, 158, 167, or 176°F.
According to WBSF results, optimum tenderness
for the strip loin occurred around 131°F.
Higher marbling protected tenderness at
higher endpoint temperatures. Tenderness
increased in bottom round and brisket muscles
as endpoint temperature increased from 104 to
140°F, then tenderness decreased as endpoint
temperature rose from 149 to 176°F. Endpoint
temperature was the only significant factor
affecting bottom round tenderness. Steaks
cooked in the water bath had higher WBSF
and, therefore, were less tender than those
cooked on the belt grill. This was true for
both the strip loin and brisket. The effect of increasing endpoint temperature on WBSF of
the strip loin was different than for the bottom round and brisket.