Collaborative Research: Ethanol Plants to Produce Animal Feeds --- Whole Conversion of Corn and Residue to Support Biofuel and Feed Production

The Food-Energy-Water (FEW) Nexus, from a global perspective, can be described as the interconnected resource systems of food, energy, and water. As the world's population expands to the expected 9 billion by 2050, there will be a need to balance difference resources across these three systems to obtain different user goals without putting undue strain on the ecosystems that provide these resources. The goal of this project is to develop FEW Nexus solutions for regions where bioenergy crop production competes with animal feed production for land, water, and energy sources. Due to the increased demand for ethanol from corn production, there is less land for animal feed production. Farmers will often use distiller's dried grains with other grain waste products to supplement animal diets. However, this feed is not digested efficiently by swine and poultry, leading to wasted nutrients and nutrient run-off to surface waters. The Hu research group at the University of Minnesota - Twin Cities, in collaboration with Chinese partners at the Dalian University of Technology, Guangxi University, Beijing Technology and Business University, and Beijing Normal University, propose to develop a fungal fermentation step during corn-ethanol processing to convert corn stillage, along with other agricultural residues, to animal feed that can be better utilized by swine and poultry. This step will ultimately reduce energy costs for the corn-ethanol production process and mitigate impacts to the interconnected FEW systems of bioenergy production and animal feed production. By testing various agricultural residues, the researchers will identify different opportunities for nutrient enhancement for swine and poultry feed which will lead to more efficient digestion by these animals and reduce nutrient run-off from incompletely digested feed.

Through the whole conversion of corn and selected agricultural residues, the principal investigator's research group, in collaboration with 4 Chinese universities, will support both the biofuel and feed production industries in interconnected food-energy-water (FEW) systems. Livestock with monogastric diets are typically fed with corn stillage, a by-product of the corn-ethanol fermentation process to reduce the cost of ethanol production. While suitable as feed for monogastric livestock, this stillage is not easy to digest. The inefficiency of stillage digestion leads lower nutrient uptake by livestock and, subsequently, the increase of nutrient run-off from animal waste. The researchers plan to study methods to improve the digestibility of this feed through fungal fermentation of this stillage, along with other residues such as rapeseed meal, during integration with corn ethanol production. First, they will evaluate the digestion efficiency of these co-products in comparison to traditional diets of corn-soybean meal and untreated corn-stillage diets to determine the best combinations of stillage and residues. Once the optimized feed mixture(s) is/are identified, life cycle analyses and techno-economic analyses will be used to identify the potential economic and environmental impacts of the new diets from synthesis to digestion and waste treatment. The research could benefit bioenergy production in both the US and China by lowering the cost and the environmental impact of corn ethanol production through the development of a higher-value byproduct of corn ethanol fermentation. The researchers plan to engage the Hmong community, an underrepresented Asian community, through community outreach, high school programs, and summer camps designed to inform these stakeholders of ways to increase their corn ethanol production income while benefiting the environment and reducing strain on the local FEW Nexus.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.