Changes and evolution of corn coproducts for beef cattle1

Abstract

The number and nutrient composition of corn-based coproducts will expand as ethanol producers seek to optimize the efficiency of ethanol production and the value of the coproducts they produce. For example, modified wet distillers grains plus solubles are produced by adding the condensed solubles to partially dried distillers grains so that the resulting product contains approximately 50% DM. Other innovative technologies have been developed to fractionate corn or distillers dried grains with solubles (DDGS), or both, for recovering additional coproducts and improving nutritional composition of DDGS. Two (i.e., wet and dry) corn-fractionation technologies have been developed to remove the germ, pericarp fiber, or endosperm fiber before fermentation, resulting in a significant reduction in the amount of DDGS produced and a corresponding increase in its protein content. Other fractionation technologies include removal of oil by centrifugation after fermentation but before DDGS production or removal of oil by solvent extraction from DDGS. Technology to recover pericarp fiber by sieving and aspiration after DDGS production has also been developed. Germ, pericarp fiber, endosperm fiber, or oil can be used as feedstocks for producing other marketable coproducts or can be used as ingredients in animal diets. One example of a new corn coproduct available to the beef industry is bran cake. This product results from combining corn bran (i.e., pericarp fiber) and distillers solubles produced from a corn dry fractionation process. When bran cake replaced a mixture of high-moisture and dry-rolled corn at up to 45% of a finishing diet, BW gains and feed efficiency were improved. In high-forage diets, the corn bran had approximately 85% the energy value of distillers grains. How rapidly these technologies are adopted will be driven by the economic advantages achieved over the traditional dry and wet milling processes.