A few laboratories are beginning to offer the "UW Grain Evaluation System," developed by researchers at the University of Wisconsin.
It is the first system to look at both the chemical and physical characteristics of starch digestibility. It includes chemical measures such as neutral detergent fiber, as well as physical measures like particle size. An interesting new parameter — prolamin — has also been added. Prolamin is a protein matrix in the corn kernel that encapsulates starch and makes it more difficult to digest.
The UW Grain Evaluation System measures prolamin, indicating whether the sample is low, medium or high. If the sample is high, it might tell the producer to do a better job with kernel processing, so that the kernels are broken up more to offset the prolamin. The values for prolamin usually fall into a general range; therefore, the test helps to find if there are any outliers in the grain samples that may need special attention, points out Pat Hoffman, dairy scientist at the University of Wisconsin's Marshfield Agricultural Research Station. The UW Marshfield Soil and Forage Analysis Laboratory offers the test, as does Dairyland Laboratories in Arcadia, Wis.