By ANN HINCH
Assistant Editor

KANSAS CITY, Mo. — The idea of using corn for something other than eating isn’t new. There was a time, after all, before whiskey, before ethanol – even before corn itself.

There are uses that even the first person to ferment corn into alcohol probably didn’t imagine. Some of those – such as cell tissue rebuilding and wood or plastic substitute – were presented during the National Corn Growers Assoc. (NCGA) Corn Utilization & Technology Conference in Kansas City earlier this month.

“Probably, it’s more important today than ever before, that we start putting these new (use) ideas in place,” said NCGA Chairman Fred Yoder, when introducing a group of speakers addressing potential new products and revenue streams for corn processors.

Dr. Chris Schilling, an engineering professor with Saginaw Valley State University in Michigan, talked about combining corn-derived distillers grains and soybean meal for bioplastics. Manufacture is still at the lab stage, he said, explaining the process by which researchers made small, flat, hard discs out of these two items mixed with other ingredients.

Essentially, he said what they produce is best compared to a wood or plastic substitute. Plastic, of course, is manufactured with petroleum, a costly material those in the biopolymers and other industries are trying to find ways to replace or reduce.

Schilling’s discs are nowhere near ready for mass production. He went over how researchers varied ingredients in different lots and how that affected color and tensile strength of the discs.

So far, even the strongest formula is still too brittle for manufacture, but by studying each ingredient’s properties, researchers hope to figure out how to improve that. Eventually, perhaps corn and soybeans could be incorporated into, say, low-cost plastic dinner plates and other everyday items.

“We’re on the low end,” he said of finding usefulness, as compared to nylon and other well-known polymers. “As you can see, we have a lot of work to do.”

Films and fibers are other types of potential uses for corn – or at least part of the corn. Dr. Yiqi Yang, a professor in textiles, clothing and design at the University of Nebraska-Lincoln, explained zein is a protein that is a preferred source for films, fibers and adhesives, but on the current market its cost runs about $10-$12 per pound to purchase from wet mills.

Zein can’t be extracted from dried distillers grains (DDGs) using the same alcohol-water process as with wet-milled, because the protein in DDGs is denatured during its creation. Yang and his colleagues have been experimenting with a way to extract this zein, however, by grinding the DDGs to powder and removing oil and pigments.
He explained he is testing this because DDGs contain 25-30 percent zein, and there are some conditions under which he’s gotten higher yield and less natural pigmentation from DDGs over commercially produced zein. Abundant DDGs could offer a cheap and easy source of the protein, Yang added.

But beyond textiles, he said when zein nano fibers are cross-linked with citric acid, the protein’s bonds were strengthened. This can be used on films and adhesives – but it’s also possible the biocompatible material could be used to repair living tissue. So far, Yang said the tissue used in experiments is not human, nor does he know of any trials involving injured human tissue – yet.
There have been no market studies on cost, but Yang said if researchers are able to get DDGs to give up their zein using “low-cost materials,” the finished fibers might still be sold cheaply enough to make it a desirable and profitable market.

One way corn could protect human tissue is as a component in sunblock. Dr. Michael Jaffe, a research professor in biomedical engineering for the New Jersey Institute of Technology (NJIT) and chief scientist of industrial programs for the state’s Center for Biomaterials, talked about how isosorbide – a corn-based chemical – could be used as a UV stabilizer in sunscreens and cosmetics because it absorbs UVB and UVA rays.

Isosorbide is a common, desirable building block, Jaffe said – it is heat-stable, soluble in water and some chemicals and is a bulky molecule. Too, it’s inexpensive. The NJIT partnered with the Iowa Corn Production Board to study how corn isosorbide could be used as a base for various products, notably plastics (such as in flexible PVC pipe) and coatings (such as epoxy resins).

Another prized quality of isosorbide is it can absorb a great deal of water, though not thoroughly enough to yet use it in, say, electronics.