"New Corn Uses Sprout from Local USDA Lab"

Greg Roth

Recently I had the opportunity to visit the USDA’s Eastern Regional Research Center (ERRC) in Wyndmoor, a Philadelphia suburb. I joined several corn producers and about 40 other folks in Late August for a very informative tour. The lab is well known for some of its achievements in the food science arena and is making its mark now in the area of biofuels research, focusing on the development of co-products from corn processing. These new co-products could lead to increased profitability from corn based ethanol plants and more use of corn for processing, which could improve the market situation for corn producers.

Corn co-products are the products that remain after processing of corn. One form of corn processing is called wet milling. In this process, corn is cooked, and then separated into the starch, protein, fiber and oil fractions. The starch is used to make ethanol, corn sweeteners, and food and industrial starch. The protein is sold as corn gluten meal (61% protein) and the fiber is sold as part of the corn gluten feed. The corn gluten feed is the least valuable of the co-products and sells for about 5 cents/lb.

At ERRC, researchers found that an edible oil could be extracted from the corn fiber. They also found that this new oil was not ordinary corn oil- it contained the highest known naturally occurring levels of phytosterols, which can reduce cholesterol. This new oil from corn fiber has been patented as "Amaizing Oil" and the lab is currently looking to commercialize the product.

Another added value use of the corn fiber has been the development of corn fiber gum. Corn fiber gum is similar to gum arabic, a common food additive. This new product is called Zeagen and efforts are underway to get this to the market palce as well.

The lab has also been working on improving the extraction of zein from corn co products. Zein is used in the food industry to form thin tasteless coatings on foods. The new process under development could reduce the cost of zein to the point where it could be used form numerous industrial applications. Two under consideration are water resistant coatings on starch based biodegradable cups and the development of biodegradable zein sheets for mulches in vegetable production.

Another method of corn processing is called the dry grind process. In this process dry corn is ground and then fermented to a beer, which is distilled to produce ethanol. The basic co-products in this process are distillers grains, used for animal feed, and carbon dioxide, which can be used for soft drink production or other industrial purposes. The dry mill process is the one that is being considered for most ethanol plants under consideration because of its lower costs. The downside is that it produces less co products than the wet mill process.

At ERRC, several researchers are focusing on improving the efficiency of the dry mill process and also creating more co-products. The lab has developed new milling techniques to separate the oil from the dry ground corn- this allows the dry mill plant to add corn oil to it co products. They also have found a way to extract fiber from the ground corn, which then allows the development of some of the other fiber based coproducts.

The lab is also currently evaluating a continuous fermentation process using carbon dioxide to "strip" the ethanol from the beer. This process, combined with the new milling technology, could reduce the cost of ethanol production by 10 cents/gallon.

We also saw a number of other interesting topics on improving the efficiency of ethanol production, including the use of hybrids that are more fermentable, the use of enzymes for pre-treatment of the ground grain

September 2001