Abstract #M452

# M452
Chemical composition and quality of fresh lamb from rationally grazed hair and wool x hair sheep lambs as influenced by soy hull supplementation.
Beruk B. Lemma*1, Jung Hoon Lee1, Stephan A. Wildeus2, Govind Kannan1, Brou Kouakou1, 1Fort Valley State University, Fort Valley, GA, 2Virginia State University, Petersburg, VA.

This study was conducted to evaluate the effects of soy hull supplementation on the quality characteristics of fresh lamb from hair and wool × hair sheep lambs. Forty-seven lambs (5-mo old), 23 purebred hair sheep (Barbados Blackbelly or BB, BW = 16.2 ± 1.9 kg; St. Croix or SC, BW = 19.5 ± 2.0 kg) and 24 crossbred wool (Dorset, D) × hair (BB; BW = 21.7 ± 2.3 kg or SC; BW = 21.7 ± 2.9 kg) sheep lambs of both sexes rotationally grazed predominately tall fescue with or without soy hull supplementation during summer. Soy hull was provided at 2.0% of BW at individual feeding stations. After 90 d of grazing, lambs were harvested using standard procedures. After 24 h cooler storage (2°C), longissimus muscle (LM) pH was measured in individual carcasses. Each carcass was fabricated to obtained 2.5-cm thick loin chops for meat quality analysis. All data were analyzed as a completely randomized design with a 2 × 2 x 2 factorial treatment arrangement: breed type (pure- or cross-bred), supplement (with or without soy hull), and sex (male or female). The CIE L* (lightness), a* (redness), and b* (yellowness) values of lamb chops were significantly influenced by supplementation, sex, and their interaction. Chops from supplemented lambs had higher (P < 0.001) CIE a* values than those from grazed-only lambs. The LM from supplemented lambs had higher (P < 0.001) protein (22.4 vs 21.4%) and fat contents (2.88 vs 2.47%) than that from grazed-only lambs. The percent metmyoglobin and thiobarbituric acid reactive substances (TBARS) values of LM from lamb chops were significantly affected by sex, breed type, and breed type × sex. The LM from purebred lambs had a higher (P < 0.05) level of TBARS (0.32 vs 0.27 mg MDA/kg) than that of crossbred lambs. Chops from supplemented lambs had lower (P < 0.01) shear values than those from grazed-only lambs. The results indicate that soy hull supplementation can improve color and texture property of fresh hair sheep lambs grazing fescue pasture regardless of breed type.

Key Words: hair and wood sheep, meat quality, soy hull