Submitted to: Animal Feed Science And Technology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/21/2010
Publication Date: 8/20/2010
Citation: Belyea, R.L., Rausch, K.D., Clevenger, T.E., Singh, V., Johnston, D., Tumbleson, M.E. 2010. Sources of variatio in composition of DDGS. Animal Feed Science And Technology, 159:122-130. Interpretive Summary: Distillers Dried Grains with Solubles (DDGS) are produced as a coproduct of the fuel ethanol industry and are used primarily as an ingredient in ruminant animal diets. The variation in nutritional composition of the DDGS reduces the quality and market value. There is little published information that addresses the specific causes of variation. To investigate potential sources of variation, samples of DDGS from dry grind processing (ethanol) plants in the upper Midwest were analyzed for nutrient concentrations and sources of variation were evaluated. The results indicated that the DDGS variation was associated with specific fermentation batches rather than being processing plant specific. The fat content of DDGS was found to be relatively uniform, but protein content varied considerably and low lysine (an important amino acid) were significant concerns. The sources of variation were most likely caused by inconsistent grain and processing conditions. These results can be used by fuel ethanol producers, researchers and animal feed suppliers to develop improved processing conditions resulting in increased nutritional quality and market value for DDGS.
Technical Abstract: High protein and high energy content make distillers dried grains with solubles (DDGS) a unique ingredient for ruminant diets, but variation in composition reduces nutritional quality and market value. There is little published information that addresses the specific causes of variation. Samples of DDGS from dry grind processing (ethanol) plants in the upper Midwest were analyzed for nutrient concentrations and sources of variation were evaluated. Significant plant × period (time) interactions indicated that variation was associated with specific fermentation batches, rather than plants or time (periods) per se. Differences in maize characteristics and in processing conditions probably were responsible for batch to batch effects. Fat content of DDGS samples was relatively uniform, but there was considerable variation in protein concentration (260–380 g/kg DM). Low lysine (8.9 g/kg DM) and elevated pepsin insoluble (bound) protein concentrations were additional concerns. Published values for ruminally undegradable protein content were as accurate as estimates using specific plant data.