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Lou Armentano: byproducts valuable part of ethanol production

[audio:http://news.cals.wisc.edu/wp-content/uploads/2011/03/lou_armentano_ethanol_DDG.mp3|titles=Lou Armentano: corn to ethanol]

Transcript:

Sevie Kenyon

Corn goes in, ethanol comes out. We are visiting today with Lou Armentano, Department of Dairy Science, University of Wisconsin Extension in the College of Agricultural and Life Sciences, Madison Wisconsin and I’m Sevie Kenyon. Lou, welcome to our microphone. What happens to corn when it goes into an ethanol plant?

Lou Armentano

Ethanol plants basically just take the corn and grind it up. Corn is about 75% starch, they grind that corn up, they digest the starch with enzymes, and then yeast uses the sugar that comes from that starch to make ethanol.

Sevie Kenyon

What comes out the other side of that process?

Lou Armentano

If you look at a bushel of corn, about a third of it ends up as ethanol which they sell, about a third of it ends up as carbon dioxide, but of course remember that the corn fix that carbon dioxide in the first place, so we really don’t worry about that as a greenhouse gas, and then about a third of it is left over after you take the starch out of corn. So the rest of corn contains basically fiber, oil and the protein that is in the corn. We really don’t think about corn grain being particularly high in either fiber or protein or oil, but once you take out the 75% that was starch, all of a sudden you have a feed that is about a third fiber, a third protein and about 15% oil.

Sevie Kenyon

And Lou, can you tell me what people do with this byproduct feed?

Lou Armentano

Well it is a great supplement for most species of animals. It can be included in dairy diets; it certainly can be included up to 15% of the diet that is usually fed at lower rates. Same thing in finishing swine, and in beef cattle it can be feed at well above those levels. In dairy we view it primarily as a protein supplement, so it is really a replacement for feeds like soybean meal than it is for a feed like corn itself.

Sevie Kenyon

Lou, can you give us an idea of how our dairy producer friends use these products on their farms?

Lou Armentano

Now many dairies feed commodity feeds. They fill up big bins and commodity sheds, and they can feed the storage grains as a pure feed. Also, if you live close to a pure plant and I think we have six plants in the state, it can be fed wet. There are some challenges to feeding it wet, but there are some energy advantages to wet because the feed does not have to be dried down. Here you are trying to produce an energy source and then you use natural gas to dry the feed down! If you could feed it wet, then that would be an energy savings. We have quite a few cows around these ethanol plants…

Sevie Kenyon

The ethanol business has expanded in recent years, can you give us an idea of the scale of these products now coming on the market?

Lou Armentano

About a quarter of every acre of Wisconsin corn is going into ethanol. It is a big impact! So when corn gets expensive, it hurts the ethanol industry, as well as making it challenging for people who have to buy corn for livestock.

Sevie Kenyon

We have been visiting with Lou Armentano, Department of Dairy Science, University of Wisconsin Extension in the College of Agricultural and Life Sciences, Madison Wisconsin and I’m Sevie Kenyon.