No abstract

A randomized complete block design with 3 replications (n = 432, 72 broilers per treatment) was used to evaluate the effects of electrical (ES) and vacuum stunning (VS) on broiler breast meat quality. Electrical stunning was performed by applying 11.5 V, <0.05 mA, AC to DC current for 3 s for each broiler. Vacuum stunning was accomplished by exposing the birds to a low atmospheric pressure of 597 to 632 mmHg in an airtight decompression chamber. Breast removal was then performed at 0.75, 2, and 4 h postmortem for each stunning method. Color, pH, cook loss, and shear force values were measured on breasts that were removed from the right side of the carcass. Breasts removed from the left side of the carcass were used for consumer acceptability testing. The L* values were lower (P < 0.05) for VS than ES at 4-and 2-h deboning times. On average, 15-min and 24-h postmortem pH values were not different (P > 0.05) for both stunning method and deboning time. Shear force did not differ (P > 0.05) between stunning methods but decreased (P < 0.05) as deboning time increased. On average, no differences (P > 0.05) existed in consumer acceptability (appearance, texture, flavor, overall) among breast meat from ES or VS birds that were deboned at 2 or 4 h. However, consumers could be clustered into 8 groups based on preference and liking of samples regarding overall and texture acceptability. Sixty-five percent of consumers (3 clusters) liked all broiler breast treatments. Within these 3 clusters, some consumers preferred (P < 0.05) 4-h deboned samples over those deboned at 2 h (cluster 7), and other consumers preferred (P < 0.05) those deboned at 2 h over 4-h samples (cluster 6). Data revealed that both stunning methods provided high-quality breast meat with minimal product differences.

Twenty-two Kiko crossbred male goats (Capra hircus; initial BW = 27.5 ± 1.04 kg) were used in a randomized complete block design to determine the effects of feeding pine bark (PB; Pinus taeda L.) on animal performance, rumen fermentation, blood parameters, fecal egg counts (FEC), and carcass characteristics in goats. Experimental treatments included the control diet [0% PB plus 30% wheat straw (WS)], 15% PB plus 15% WS, and 30% PB plus 0% WS (on as-fed basis), where PB replaced WS. Freshly air-dried PB and WS were finely (1.5 to 3.0 mm) ground and incorporated in the grain mixes. Experimental diets provided a total of 1.9, 16.3, and 32 g of condense tannins (CT)/kg DM in 0%, 15%, and 30% PB diets, respectively. The grain mixes were fed daily at 85% of the feed offered, with remaining 15% consisting of Bermuda grass hay (Cynodon dactylon). Animals were fed once a day at 0800 h, and feed offered and refused was monitored for an 83-d performance period. Rumen and blood samples were collected at d 0, 50, and 80 of the study. Carcass traits were assessed after slaughter at the end of performance period. There was no difference in initial BW, hay, and total NDF intake among treatments; however, final BW (P = 0.06), ADG (P < 0.01), grain mix intake (P < 0.001), total DMI (P < 0.001), and G:F (P < 0.04) increased linearly as the PB increased in the diets. Rumen ammonia N, acetate, isovalerate and acetate-to-propionate ratio were reduced linearly (P < 0.05). There was no difference in carcass traits except cold carcass weight (P = 0.06), which tended to increase linearly in goats fed 15% and 30% PB. Breast, sirloin, trim trait, liver, and hide weight increased (linear; P < 0.01) with addition of PB. Blood basophils, alanine transaminase, aspartate aminotransferase, albumin, Na, and Cl concentrations decreased (linear; P < 0.02 to 0.01) as PB supplementation increased. Supplementation of PB reduced (linear; P < 0.01) average FEC. Addition of PB in the diets improved performance, reduced FEC, and favorably modified rumen fermentation.

No abstract

The objectives of this study were to evaluate visual and chemical attributes of beefsteaks from various USDA quality grades and muscles packaged in high-oxygen (80% O2/20% CO2) modified-atmosphere packaging (MAP). A total of nine carcasses were selected to represent Select (n = 3), low Choice (n = 3), and high Choice (n = 3) USDA quality grades. The semimembranosus (SM), semitendinosus (ST), and biceps femoris (BF) muscles were removed from each carcass and allotted to two packaging types (MAP or polyvinyl chloride over-wrap) and were displayed for up to 10 d, with evaluation on d 1, 3, 5, 7, and 10. Fifty-four steaks were evaluated on each day by a five-member trained panel for visual color (lean color and discoloration) and were also analyzed with a Minolta Chroma Meter CR-310 for L* and a* values (lightness and redness, respectively). Chemical properties measured included percentage of metmyoglobin formation and fat content. Visual color scores did not differ (P > 0.05) at d 1 and 3 with respect to all quality grades, but decreased after d 3, with a greater reduction (P < 0.05) in high Choice steaks for both lean color and discoloration. The low Choice steaks packaged in MAP displayedhigher (P < 0.05) lean color scores and less (P < 0.05) discoloration at d 7 and 10 than did Select and high Choice steaks. Redness (a*) values also decreased (P < 0.05) after d 3, whereas (lightness) L* values declined (P < 0.05) from d 1 to 5. The high Choice steaks had higher (P < 0.05) metmyoglobin content than low Choice and Select steaks, but packaging had no effect (P > 0.05) on metmyoglobin content. Muscle type did affect metmyoglobin content; however, the metmyoglobin content of the SM was greatest (P < 0.05), followed by the BF, with the ST having the lowest (P < 0.05) metmyoglobin formation. Results indicate that low Choice steaks react the best in MAP, and the ST maintained greater storage characteristics regardless of quality grade or packaging.