Hard Oats Stand the TestBy
Plant breeders can identify oat varieties that turn out a good
measure of nutritious oatmeal with an instrument that
Agricultural Research Service
scientists invented several years for a different purpose: to classify
wheat as hard or soft.
Called a single kernel hardness analyzer, the instrument reveals
whether oats are hard or soft. If the oats are hard, they can be
dehulled with less likelihood their insides--known as groats--will
break in the process, according to findings by scientists at the ARS
Research Laboratory in Fargo, N.D.
Fewer broken groats mean more and bigger flakes of rolled oats and
fewer siftings channeled into less valuable animal feed.
The single kernel hardness analyzer was invented at ARS' U.S. Grain
Marketing and Production Research Center in Manhattan, Kan. ARS
patented (#5,005,774) the invention in 1991.
The analyzer was one of three hardness instruments that the Fargo
scientists used for their oat study. It weighs one kernel at a time,
then crushes it to gather measurements of moisture, hardness and size.
In recent experiments with six genetically diverse oat cultivars,
the scientists first dehulled identical samples using a high-pressure
air stream that blows kernels against a corrugated metal wall. Then
they tested hardness of each sample and found that the harder kernels
generated fewer broken groats. Also, when moisture levels remained
above 8 percent during dehulling, fewer groats broke during dehulling.
In addition, the scientists found that the oat cultivars that
produced fewer numbers of broken groats also had higher levels of
beta-glucan. Beta-glucan has been shown to decrease blood serum
Next the scientists will confirm whether the relationship between
hardness and beta glucan content holds true with more oat varieties
grown in diverse environments. If so, plant breeders could more easily
breed the two traits at the same time.
Scientific contact: Douglas C. Doehlert, ARS
Research, Fargo, N.D., phone (701) 239-1413, fax (701) 239-1377,