Department of Animal and Dairy Science, University of Georgia, Athens 30602, USA.
J Anim Sci. 2011 Nov;89(11):3792-802. doi: 10.2527/jas.2011-4154. Epub 2011 Jun 3.
The objective of this study was to evaluate the meat quality and shelf life of steaks from steers fed dried distillers grains with solubles (DDGS) or dried corn gluten feed (CGF) compared with soybean meal with corn (SBM) as a protein supplement from weaning to slaughter. Angus cross steers (n = 81; BW = 306 ± 26.1 kg) were randomly assigned to pens (n = 9) and fed a stocker diet of corn silage (75% of DM) with DDGS, CGF, or SBM and ground ear corn. After 84 d of stockering, 12 steers (BW = 397 ± 15.3 kg) were randomly selected from each treatment and finished using the same protein supplement at 25% of DM for 100 d. Carcass data were collected (24 h) and the longissimus lumborum was fabricated into steaks at 48 h postmortem. Steaks were assigned to proximate analysis, Warner-Bratzler shear force (7-, 14-, or 21-d aging), and retail display (1, 3, 6, or 9 d). Protein source did not affect carcass yield, quality, or longissimus lumborum composition (P > 0.05). After 7 d of aging, DDGS and CGF steaks were more tender (P < 0.01) than SBM, but were similar (P = 0.30) after 14 and 21 d of aging. Feeding corn by-products did not influence subjective overall color acceptance (P = 0.17) in this study, but acceptance declined over time (P < 0.01). Subjective redness was similar (P > 0.05) among diets except SBM steaks were more red (P < 0.01) than DDGS after 9 d. On d 3 and 6 of retail display, CGF steaks exhibited more discoloration (P < 0.04) than SBM or DDGS steaks. However, after 9 d DDGS steaks were more discolored (P < 0.01) than CGF or SBM. Objective L* was lighter for CGF (P < 0.04) over 9 d of display, and all treatments became darker (P < 0.01) as time increased. Redness (a*) declined (P < 0.01) over time with SBM steaks maintaining more color in the red spectrum than CGF and DDGS after 6 d of display. Protein source did not affect (P > 0.05) the rate of lipid oxidation. Total SFA concentrations were similar (P > 0.05) among treatments; however, total MUFA were less (P < 0.05) and total PUFA concentrations were greater (P < 0.05) in DDGS steaks compared with SBM or CGF steaks. These data show that DDGS or CGF can be fed as a protein supplement at 25% DM from weaning until slaughter while maintaining meat quality when compared with steers fed soybean meal as a protein supplement.
本研究旨在评估与用大豆粉（SBM）作为蛋白质补充料从断奶至屠宰相比，用干酒糟及其可溶物（DDGS）或干玉米面筋饲料（CGF）喂养的育肥牛的肉质和货架期。 Angus 杂交公牛（n=81；BW=306±26.1kg）随机分配到围栏（n=9），并喂食含有 DDGS、CGF 或 SBM 和地面玉米的青贮玉米（DM 的 75%）。在育肥 84d 后，从每个处理中随机选择 12 头（BW=397±15.3kg）公牛，并在 DM 的 25%下使用相同的蛋白质补充料进行 100d 的育肥。收集 carcass 数据（24h），48h 后将腰最长肌加工成牛排。牛排进行近似分析、华纳布拉兹勒剪切力（7、14 或 21d 老化）和零售展示（1、3、6 或 9d）。蛋白质来源不影响 carcass 产率、品质或腰最长肌组成（P＞0.05）。在 7d 老化后，DDGS 和 CGF 牛排比 SBM 牛排更嫩（P＜0.01），但在 14 和 21d 老化后相似（P=0.30）。本研究中，用玉米副产品喂养并不影响主观整体颜色接受度（P=0.17），但颜色随时间推移而下降（P＜0.01）。除 SBM 牛排比 DDGS 牛排更红（P＜0.01）外，日粮之间的主观红色无差异（P＞0.05）。在零售展示的第 3 和 6d，CGF 牛排比 SBM 或 DDGS 牛排更容易变色（P＜0.04）。然而，在 9d 时，DDGS 牛排比 CGF 或 SBM 牛排更容易变色（P＜0.01）。在 9d 的展示过程中，CGF 的客观 L值更亮（P＜0.04），并且随着时间的增加，所有处理的颜色都变暗（P＜0.01）。红色（a）随着时间的推移而下降（P＜0.01），与 CGF 和 DDGS 相比，SBM 牛排的红色光谱中的颜色保持得更多，在 6d 的展示后。蛋白质来源不影响（P＞0.05）脂质氧化的速度。总 SFA 浓度在处理之间相似（P＞0.05）；然而，与 SBM 或 CGF 牛排相比，DDGS 牛排中的总 MUFA 较少（P＜0.05），总 PUFA 浓度较高（P＜0.05）。这些数据表明，用 DDGS 或 CGF 作为蛋白质补充料从断奶至屠宰时可作为蛋白质补充料以 25%DM 喂养，同时与用大豆粉作为蛋白质补充料喂养的育肥牛相比，可保持肉品质。
