Effects of steam-flaked sorghum grain or corn and supplemental fat on feedlot performance, carcass traits, longissimus composition, and sensory properties of steers

摘要

One hundred forty British x Exoticcrossbred, yearling steers (370 kg) were used in a 2x 2 factorial experiment to evaluate main effectsand the interaction of grain type (steam-flakedsorghum grain [SFSGI or steam-flaked corn [SFCI)and level of supplemental fat (0 or 4% yellowgrease WGll on feedlot performance, diet NEconcentration, carcass traits, and chemical compositionand sensory properties of longissimusmuscle. Steer performance and estimated dietaryNE, and NE, values were not different betweenSFSG and SFC. Supplemental YG improved CP 5.05) gain/feed and estimated NE, and NE, of bothSFSG and SFC diets. Compared with steers fedSFSG, steers fed SFC had a more yellow (P c .05)subcutaneous fat color. Supplemental YG had anadditive effect (P c .025) on yellow color ofsubcutaneous fat but improved (P c .08) the leancolor of longissimus muscle. Grain type or supplementalYG had no effect on sensory properties or mechanical shear of longissimus muscle. Longissimusmuscle cholesterol content was elevated (Pc .05) by supplemental YG (.49 vs .52 mg/g of wettissue for 0 vs 4% YG, respectively); however, thebiological significance of this result is question ,-ble. Similarly, effects of YG on increased (P c .05)stearic acid concentration and a higher concentration(P c .051 of linoleic acid measured in longissimusmuscle of steers fed SFSG vs SFC weresmall in magnitude. These data indicate thatunder the conditions of this experiment, NEcontents of SFSG and SFC were similar. Beefproduced from sorghum grain is similar in qualityand sensory properties to that produced fromcorn. There was no correlation (r = -.001) betweendegree of marbling and tissue cholesterol content,suggesting that for closely trimmed beef cuts,selection for higher quality by consumers will notelevate cholesterol intake.