Ethanol plants extract more value out of the corn kernel and develop more byproducts to meet specialized requirements
SAN ANTONIO, Texas — The value of distillers grains as livestock feed is well accepted, but new technologies are extracting new co-products with specific benefits.
Dried distillers grains are an internationally traded commodity but wet distillers co-products are often used locally where farms are located close to an ethanol plant. Most of the wet product goes to beef cattle.
In the United States, about half the DDGs available are fed to cattle, 31 percent to dairy, 15 percent to swine and the rest to poultry, said Dan Loy of the Beef Centre at Iowa State University.
The energy value of distillers grains is often benchmarked against corn grains.
“Wet distillers grains at lower inclusion rates have a much higher energy value than corn. The traditional distillers grains are one of the only byproducts that we can feed in a finishing beef cattle ration and actually increase the energy level of that ration, which is of tremendous value,” said Loy at a special session of the National Cattlemen’s Beef Association convention held in San Antonio
Through the work of nutritionists, more DDGs are being used as a replacement for corn.
“We have gone from feedlot rations that were 50 to 70 percent corn to feedlot rations that are less than 50 percent corn because of the substitution of distillers grains,” he said.
New variations are also entering the market. Ethanol plants are extracting more value out of the corn kernel and developing more byproducts.
Modified distillers grains are intermediate to dry distillers grains and also provide good energy value.
Other plants are removing more oil from the corn and that has had an effect on energy value relative to corn of about 1.6 percent lower.
Full fat distillers grains are 10 to 12 percent fat or more with 30 percent more energy value than corn. Low oil distillers grains are five to eight percent. De-oiled DDGs have about two to six percent fat.
Lower oil content byproducts still have about the same energy value as corn. Ultra-low oil content is the equivalent of corn gluten feed, said Loy.
The value of these products is changing depending on the oil content. Each ethanol plant has a different process and so every product is different from plant to plant. Producers are advised to consult a nutritionist to make sure the products fit into the feeding program.
Prices of these products vary. There were times when DDGs were priced higher than corn so nutritionists used the product for protein value rather than energy content.
DDGs used to cost 60 to 80 percent of the price of corn but more recently they have settled around 80 to 90 percent, said Loy.
Nevertheless, it is an economical feedstuff and can be used as a good protein source for those with access to a local ethanol plant.
New co-products are the result of fractionation of the corn kernel.
These new processes derive more byproducts with animal feed value.
Fractionation yields a product that is closer to the byproduct obtained from a plant that produces corn sweeteners. It can yield a product with up to 50 percent protein.
Valuable co-products could be higher protein derivatives and yeast, said Pete Williams of Fluid Quip Technologies, a company developing corn fractionation technologies to pull out more co-products.
“Some of the components of DDGs are worth more than the actual entire DDGs,” said Williams.
DDGs have about six percent yeast resulting from the fermentation process. Yeast is useful for cattle for immunity and digestion.
Most plants will continue to produce traditional ethanol and co-products but a small number may go further to extract other valuable components.
Traditional DDGs have 30 percent protein and less than 10 percent crude fibre so balancing rations is necessary.
“That amount of protein with that amount of fibre is not good for nutrition. We want to get it out to a wider range of livestock. To get it out to other species we cannot have that amount of protein and that amount of fibre in the same place,” Williams said.
High percentage protein products could go to pets, aquaculture, swine and poultry, whereas cattle need more fibre.
If a cattle ration includes 30 percent DDGs, the protein in that product is actually being wasted because animals are getting 20 to 30 percent above the protein requirement. New technology removes that excess protein and the bran feed is left, which offers high energy and fibre for ruminants, said Loy.
“It provides nutrients for the species that can really use them and that adds value to the whole process,” said Loy.