Journal of Animal Science, Vol 68, 148-154, Copyright © 1990 by American Society of Animal Science

Effects of Grains, Marbling and Sex on Pork Tenderness and Composition

¹ Texas Tech University, Lubbock 79409

Crossbred barrows and gilts (n = 216) were fed corn, sorghum or wheat as the dietary grain source to determine their effects on carcass characteristics. Corn-fed pigs had larger loineye areas than sorghum-fed pigs but less marbling than wheat-fed pigs (P < .05). Carcasses of 45 barrows and 43 gilts were selected to fit three marbling groups (L = "traces" and "slight"; M = "small" and "modest"; H = "moderate" to "abundant") within grain sources to determine the effects of feed grains, marbling and sex of pig on pork composition and tenderness. Warner-Bratzler shear (WBS) values for these selected pigs showed that the corn-fed group was .45 kg more tender (P < .05) than the sorghum-fed group, but all groups were acceptably tender. Corn-fed pigs had 6 µm larger (P < .01) longissimus myofiber diameters at the 11th rib than the wheat-fed pigs, and gilts had larger (P < .05) fiber diameters than barrows. WBS and Amour Tenderometer values for cooked muscle decreased linearly (P < .002) as marbling increased (L, 3.62 kg, 17.48 kg; M, 3.24 kg, 16.85 kg; H, 2.99 kg, 15.14 kg; SE = .33 kg, 1.17 kg, respectively). Marbling score was related negatively (r = -.35) to both Tenderometer and WBS values of cooked muscle.

Key Words: Carcasses • Feeds • Pigs • Pork • Tenderness • Marbling

Submitted on June 27, 1988
Accepted on May 22, 1989