Effects of high oil corn on carcass characteristics, fatty acid profiles, beef palatability, and shelf life traits of beef top loin steaks

Recent development of com having greater oil content offers the opportunity for added benefit to carcass and palatability characteristics of beef. The objective of this study was to determine if feeding high oil com to finishing feedlot steers had an added benefit as compared to normal mill run corn plus added fat. One hundred twenty Angus steers were assigned randomly to either Normal or High Oil treatments. Pens (12 pens per treatment with five steers per pen) were assigned randomly to one of the following dietary treatments: (1) normal based diet (NMR) of mill-run steamflaked corn plus added fat, (2) high oil diet (HOC) based on high oil steamflaked corn. On the morning of d 165, 117 of the original 120 steers were shipped to a commercial packing facility. At 48 h postmortem, carcass data was collected on all carcasses. Carcasses were then randomly selected (2 carcasses from each pen) and 180A strip loins were collected. One steak was removed for retail display at d 14. Two steaks (2.5 cm thick) were removed from each strip loin for sensory panel analysis and Wamer-Bratzler Shear Force determination after 14-d aging. No treatment differences were observed (P > .05) between fat thickness, ribeye area, KPH, hot carcass weight, yield grade, and skeletal and lean maturities. Marbling scores and quality grades were higher (P < .05) for NMR than HOC. Overall 88% of the NMR steers graded Choice compared to the 84% for HOC. Sensory traits as well as Warner-Bratzler Shear Force determinations did not differ (P > .05).

No significant differences were determined for purge loss, fat and moisture percentages, nor fatty acid analysis with the exception of linoleic acid. HOC had a higher level (P < .05) of linoleic acid than did NMR. Feeding high oil com failed to improve carcass quality, palatability, and conjugated linoleic acid levels.