Ethanol Coproducts

What are Distillers Grains?
A bushel of corn used in the dry grind ethanol process yields 2.8 gallons of ethanol, 17 pounds of carbon dioxide, and 16 pounds of distillers grains. These residual grains are used as a quality source of energy and/or protein in beef, dairy, swine, and poultry rations. If fed in local livestock markets, the product is normally sold as “wet distillers grains (WDG).” If transported to distant markets or exported, the product is dried at the plant and becomes “dried distillers grains (DDG).” In many cases, the solubles stream, or syrup, from the fermentation process is mixed in with the distillers grains, resulting in “WDGS” or “DDGS.”

Production
In the 06-07 marketing year, it is projected that 12.2 million metric tons of distillers grains will be produced. In 07-08, it is projected that more than 17 million metric tons will be produced. The supply of distillers grains has a displacement effect on the corn feed market. In 06-07, distillers grains displaced an estimated 512 million bushels of corn from feed markets, making that corn available for other uses. (source: ProExporter Network, May 07).

Domestic Demand
To date, demand for distillers grains has kept pace with supply. Nearly 90% (or approximately 10.8 million metric tons) of the distillers grains produced in 06-07 were sold into domestic feed markets. While the majority of domestic distillers grains consumption occurs within the Corn Belt (in close proximity to the production source), a significant amount of product is also shipped by rail to concentrated feeding operations outside of the Corn Belt. For example, a significant amount of DDGS is regularly shipped to beef feedlots in the Texas Panhandle and dairies in California.

Export Demand
Demand for distillers grains in foreign feed markets is also increasing. In 2006, more than 1.25 million metric tons (or 10 percent of total production) of distillers grains were exported. By comparison, 787,706 metric tons were exported in 2004. The top five exports markets (2006) in descending order are: Mexico, Ireland, Canada, Taiwan and the United Kingdom. (source: FAS-USDA). Exports to North America (Mexico and Canada) and the Pacific Rim have shown the greatest growth in recent years, while exports to Europe have generally declined slightly.

Consumption by Species
Because distillers grains are well suited to ruminant animal diets, the majority of the product is fed to beef and dairy. However, swine and poultry consumption is increasing steadily as the feed industry gains a better understanding of how to best utilize the product in those rations. According to Commodity Specialists Company, dairy accounted for 46% of 2006 distillers grains consumption in North America, while beef accounted for 42%. Swine accounted for 9% of the North American distillers grains use, while poultry made up 3%.

Nutritional Characteristics
When corn goes through the dry grind ethanol process, its nutrients (with the exception of starch) are concentrated by a factor of three in the distillers grains. The following nutritional profile is typical of modern DDGS.

Source: U of Minnesota, Dr. Gerald Shurson (analysis of 32 U.S. Corn DDGS sources)

Feeding Recommendations
The following are generally accepted distillers grains feed ration inclusion levels, though all rations for specific herds should be formulated by a qualified nutritionists.

Source: Various feeding trial results

Research and Market Development Focal Areas
The ethanol industry and academia are conducting a considerable amount of research on distillers grains quality and utilization. Additionally, the industry and trade groups are engaged in a variety of market development activities. The following focal areas are of the highest priority.

• Improving nutritional quality
• Optimizing inclusion rates
• Improving flowability and transportation characteristics
• Standardizing distillers grains analytical methods
• Mitigating mycotoxin contamination potential
• Alternative uses of distillers grains
• Environmental issues related to feeding distillers grains in confined facilities

Wet Milling

The coproducts of wet milling are also very beneficial as a nutrient source for livestock and poultry. Corn Bran, Corn Gluten Feed, Corn Gluten Meal, Corn Germ Meal and Condensed Fermented Corn Extractives (steepwater) are all coproducts of the wet milling process used as livestock feed. For more information on wet milling visit the Corn Refiner’s Association.

MORE INFORMATION ON ETHANOL

Links to More Information

Pork Science - Nutritional Efficiency

New Guidelines for Distillers Grains Analysis

Distillers Dried Grains with Solubles (DDGS) in Livestock and Poultry Feeds

Distillers Grain Technology Council

IDALS