Industry Resources: Co-products
While ethanol production consumes the grain's starch, the protein, minerals, fat and fiber are concentrated during the production process to produce a highly valued and nutritious livestock feed. For dry mill ethanol refineries, which make up the majority of production, most feed is dried and sold as Distillers Dried Grains with Solubles (DDGS). A modern dry-mill ethanol refinery produces approximately 2.8 gallons of ethanol and more than 17 pounds of distillers grains from a bushel of corn. In 2012, ethanol biorefineries produced nearly 34.4 million metric tons of high quality livestock feed. This includes 31.6 million metric tons of distillers grains and 2.8 million tons of corn gluten feed and meal.
Historic Distillers Grains Production from U.S. Ethanol Biorefineries:
Though beef, dairy, swine and poultry have been the primary consumers of co-products historically, an increasing amount of research is being conducted that examines the effects of feeding co-products to other species, such as goats, sheep and fish. The use of ethanol co-products in human food applications is another area of increasing scientific interest.
"The use of wet distillers grains has been tremendously positive with regard to the average daily gain of our high stress cattle. The greatest benefit has been the ability to get them on the growing ration in half the time as previously."
Greg Gleue, Neosha Valley Feeders, LeRoy, Kansas
"Research conducted at several universities as well as the University of Minnesota has shown that corn DDGS contributes several valuable nutrients in poultry diets including energy, amino acids and phosphorous. In Minnesota, DDGS is used regularly in turkey diets as an economical feed ingredient and high quality products are in demand."
Dr. Sally Noll, Professor of Poultry (Turkeys) Science, Department of Animal Science, University of Minnesota
Exports: Internationally, distillers grains are gaining widespread acceptance as a high quality livestock feed component. These markets are particularly important to the U.S. as domestic co-products markets near saturation.
Investing to Improve Quality
Ethanol producers are investing in new technologies to improve the quality and quantity of the livestock feed they produce. A number of dry mills are installing technology that allows them to separate crude corn oil from the stillage at the back end of the process. This crude corn oil can be sold into the feed market (particularly for poultry), further refined and sold into the human food market, or used as a feedstock for biodiesel.
Guidelines are also available for analyzing DDGS. A year-long study funded jointly by RFA, the National Corn Growers Association, and the American Feed Industry Association (AFIA) offers recommended test methods for determining the moisture, crude protein, crude fat, and crude fiber content of DDGS. These factors are often viewed as the key determinants of the market value of the product. Historically, the lack of “standard” empirical DDGS test methods has led to results that vary significantly from laboratory to laboratory, causing product uncertainty for producers, marketers, nutritionists, regulatory bodies and — most importantly — distillers grains customers. RFA believes the widespread voluntary adoption of recommended test methods will reduce market confusion and add more structure to the DDGS marketplace. Click here for the report.
- A Guide to Distiller's Grains with Solubles
U.S. Grains Council, October 2012
- Fueling a Nation, Feeding the World: The role of the U.S. ethanol industry in food and feed production
Geoff Cooper, Renewable Fuels Association, May 2011
- Market Issues and Prospects for U.S. Distillers' Grains
Hoffman and Baker, U.S. Department of Agriculture Economic Research Service, December 2010
- AFIA Educational Materials
- Distillers Grains Testing Guidelines (RFA, NCGA, AFIA)
- A Scientific Assessment of the Role of Distiller’s Grains (DGS) and Predictions of the Impact of Corn Co-Products Produced by Front-End Fractionation and Back-End Oil Extraction Technologies on Indirect Land Use Change
Dr. Jerry Shurson, Professor, Dept. of Animal Science, University of Minnesota
- RFA's Comments on GIPSA's Proposed ANOPR, "The Role of USDA in Differentiating Grain Inputs for Ethanol Production and Standardizing Testing of the Co-Products of Ethanol Production"
- Distillers Grains Technology Council
- FDA's Center for Veterinary Medicine
- Grain Inspection, Packers and Stockyards Administration (GIPSA) www.gipsa.usda.gov
- Iowa Department of Agriculture and Land Stewardship
Office of Renewable Fuels and Co-Products
- National Corn Growers Association
- National Grain Sorghum Producers
- University of Minnesota DDGS
- U.S. Grains Council