Hans Van Leeuwen, professor of civil, construction and environmental engineering and his team of researchers have developed a process that could save millions of dollars on ethanol production.

The ‘MycoMeal’ process uses a fungus called Rhizopus oligosporus, which cleans water from ethanol production so that it can be recycled back into fuel production. The fungus also makes a high-quality, high-protein animal feed from the leftovers of ethanol production.

“The original work started out about 20 years ago in South Africa, and the concept of working on the fungi and thin stillage with the ethanol industry has been about 6 years now,” Van Leeuwen said. 

In producing one gallon of ethanol, there are about five gallons of leftovers known as stillage.

“The MycoMeal process would essentially lower the whole cost of the ethanol production process because in regular production, they have a very expensive way of getting rid of the excess thin stillage by evaporation,” Van Leeuwen said. “We avoid that.”

He explained that the MycoMeal process also reduces the amount of water consumption ethanol production requires.

“Usually, about six gallons of water are needed to make one gallon of ethanol. This process brings that ratio down to about four to one, since the water is being recycled,” he said. “The actual amount of energy is very difficult to quantify in those terms, but as an estimate, it could come down about 20 percent.”

The animal feed is proving to have great value as a meat substitute for human consumption. It is rich in protein, certain essential amino acids, and other nutrients.

“If you are a vegetarian, it’s hard to get all your amino acids — you must plan your diet carefully. But the fungi are a very good source of these important amino acids,” Van Leeuwen said. “Since fungi are more closely related to animals than plants, the digestibility of these amino acids is very high. Also, fungi are filamentous, so the meat substitute that you can make from this has the texture of meat, which is lacking in other kinds of substitutes.”

To give laypeople an idea of its value, he explained, “The cost of MycoMeal on a large scale could be estimated to be a $100 per ton, which is about only a few cents a pound — which is very cheap for human food. Soy meal, on the other hand, costs about $250 per ton.”

Corn is the most abundantly subsidized food crop in the United States by a wide margin. 

“Subsidies actually don’t even really benefit the agricultural sector, because it’s the oil companies that get the subsidies for using ethanol,” Van Leeuwen said. “The subsidies are actually dwindling in reality.”

Van Leeuwen explained that the current situation is often blamed for rising food prices around the U.S.

“This is not quite true because the corn that is used in ethanol production — the yellow dent corn — cannot be used for food,” Van Leeuwen said. “There isn’t a very high demand for food-grade corn in the U.S. When you really analyze it, the impact of growing corn for ethanol production is minimal on food prices.”

Currently, researchers are looking into other ethanol-producing technologies, such as lignocellulosic ethanol.

“The federal government is pushing for this new, second-generation ethanol. A lot of money has been spent on it. However, it has not yet produced any ethanol,” Van Leeuwen said. “It’s still a long way off, and they have not found an economical way to produce ethanol from lignocellulosic material. Just about all the ethanol produced still comes from corn.”

 

Van Leeuwen said the MycoMeal process has received tremendous support so far. 

“Our research is supported by the Iowa Energy Center and a Smithfield grant from the Office of the Iowa Attorney General, Lincolnway Energy of Nevada, Cellencor Corp. of Ames and Iowa State’s Center for Crops Utilization Research and BioCentury Research Farm,” he said. “We are very grateful for their help.”

Their next step is to scale up the process.

“The intermediate step was very important for us. From the lab scale to the pilot plant stage was a whole new challenge, and it proved to be much more economical than we had anticipated. The pilot plant stage has allowed us to test the energy consumption,” Van Leeuwen said. “At the end of the coming year, we hope to find funding in place to do this on a much larger scale, maybe a semi-commercial scale.”