Hulless barley: Source for ethanol?

As oil prices escalate toward the once unheard price of $100 per barrel, scientists across the country are scrambling to find biomass crops to provide maximum gallons per acre.

Corn and soybeans are the most common crops used to make ethanol and biodiesel, but storage capabilities make development of off-season crops more desirable.

One of the more interesting combinations of crops for ethanol is year-round production of corn and hulless barley. Hulless barley varieties produce higher starch content per acre than corn and could fit ideally into a double-crop system.

The price for winter barley has declined slowly, but steadily, for the past decade. Even though winter barley has long been a favorite small grain crop of farmers in the Carolinas and Virginia, most stopped producing it because it was not profitable

Plant breeders at Virginia Tech University recently released Thoroughbred and Price varieties of hulled barley that have higher starch and energy content, therefore, better feed. Virginia Tech released the first winter hulless barley cultivar, “Doyce,” in 2003.

Doyce, is a hulless barley that is high yielding, mid-season maturity, and short in stature with stiff straw. Doyce provides winter barley producers and end users with a new value-added crop having grain that is lower in fiber, higher in starch and metabolizable energy than traditional hulled winter barley, and having potential for use in feed, food and ethanol production.

Similar research is under way at Oklahoma State University by USDA Research Geneticist Dolores Mornhinweg and OSU Professor Jeff Edwards. These tests are geared to developing and releasing hulless varieties ideally suited for the ethanol industry in the Southwest.

Hullless barley has many of the same growth characteristics as wheat. Hulless barley is higher in starch and lower in fiber, characteristics that could be a bonus for upper Southeast farmers and livestock producers.

The high starch component makes hulless varieties highly desirable for conversion to ethanol. The first Southeastern ethanol plant, now under construction in Aurora, N.C., faces a challenge of supplying enough corn year-round to produce the desired 108 million gallons of ethanol a year. North Carolina is a corn-deficient state, creating an instant demand for an alternative source of starch for ethanol production.

With similar growth characteristics as wheat, hullless barley also fits well into conservation programs that bring added revenue to a farm. By keeping a crop on the soil over the winter, farmers can get the added benefits of nitrogen and carbon building, plus have a valuable crop to harvest in the spring.

For growers considering planting hulless barley for the 2006-2007 growing season, it is critical to know the seed source.

Growers should be sure to check that the seed lot is not contaminated with regular hulled barley seed. Hulless barley has an exposed embryo, so growers should pay special attention to avoid damage. However, germination rates below 90 percent are common and seeding rate must be adjusted to account for germination rate losses.

At present there are two major types of hulless barley, normal and waxy. The normal type has the traditional ratio of amylose to amylopectin starch fractions as found in regular barley. The waxy type has a higher percentage of amylopectin starch. Waxy type varieties are being tested at a number of research sites in the Southeast and Southwest, because of their desirability for use in ethanol production.

Another benefit of using hulless barley for ethanol production is the by-product, a high quality livestock feed, is subject to fewer harvesting restrictions than barley sold for human consumption.

Grain destined for human consumption must be free of hulls, have four percent or less cracked and broken kernels, be fully mature and appear bright, clean and free of diseased, frosted, sprouted or strained kernels.

Feed quality grain, by comparison, allows hull content of up to 15 percent, a maximum of 10 percent sprouts and 15 percent broken kernels, and heated, rotted or mildewed kernels less than 0.5 percent.

There are some physical harvesting restrictions seen by growers. Most importantly, barley must be dry when it is combined to successfully remove hulls, otherwise moist hulls will stick to the kernel. Though hulls can be removed by gentle buffing, this adds to the cost of crop production.

Hullless barley is heavy, producing a bushel weight similar to wheat. It is much heavier than conventional barley and will occupy about one-third the amount of space per volume as traditional barley.

As the fuel crisis continues to grow in the U.S., it is likely the interest in alternative fuel crops will also escalate. With corn for ethanol leading the way, the need for a winter crop, like hulless barley, is going to be high.

The Aurora, N.C., plant, for example, can only store about a week's worth of corn needed to fuel the giant ethanol production plant there. A winter crop, like hulless barley could alleviate many of the storage and acquisition problems the plant will encounter in the spring.

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