Use of co-products from biofuels as a feed source for cattle and influence on the meat industry

Abstract

Scope and Method of Study: Due to increased production of ethanol, frequency of distillers grains (DG) is on the rise. The objective was to determine the effects of wet (WDG) or dry (DDG) distillers grains on final product quality. Steers (n = 176) were assigned to one of five treatment groups: steam flaked corn (SFC), 10% DDG, 10% WDG, 20% WDG or 30% WDG. The objectives were to determine the effects of feeding higher levels of WDG, or DDG on carcass characteristics, meat quality, retail case life and fatty acid composition of longissimus muscle. Steaks, 2.54 cm, were cut from strip loins and identified for simulated retail display, Warner-Bratzler shear force (WBSF) analysis, sensory panel determination, and fatty acid composition.

Findings and Conclusions: Treatment had no effect on adjusted fat thickness and USDA yield and quality grades. Steaks from cattle fed 10% WDG and 30% WDG had lower WBSF values than steaks from cattle fed 20% WDG. Trained sensory panelists found no differences in overall tenderness and off-flavors. No effects were found in total saturated and monounsaturated fatty acid composition among treatments, however, 20% and 30% WDG had a higher proportion of polyunsaturated and n-6 fatty acids than 10% WDG. Data suggest that feeding WDG at higher levels, 20% or 30%, does not affect sensory attributes, however, shelf life of strip loin steaks from those treatment groups had a shelf life. Further research needs to be conducted to evaluate methods that aid in increasing shelf life of steaks from cattle fed higher rates of WDG.