USE OF ASPIRATION AND THE SINGLE KERNEL CHARACTERIZATION SYSTEM TO EVALUATE THE PUFFED AND SHRIVELED CONDITION OF SOFT WHEAT-GRAIN

Shriveled kernels lower wheat test weight and reduce milling flour yie lds. Test weight is also lowered by rain-dry cycles that cause kernels to puff (exhibit, in part, loosened layers of pericarp). A numeric sc ore was developed for degree of puffing and for degree of shriveling b ased on simple measurement devices. Wheat samples were evaluated for t est weight and Single Kernel Characterization System (SKCS) hardness i ndex, SKCS kernel weight, milling flour yield, and kernel density (hex ane displacement). Those evaluations were performed before and after s amples were air-aspirated to remove all shriveled kernels. Test weight , SKCS hardness index, and density of aspirated samples were used to d evelop a puffing score. Changes (resulting from aspiration) in test we ight, SKCS kernel weight, and flour yield were used to develop a shriv eling score. Higher puffing scores were related to elevated a-amylase activity. Puffed kernels were softer and were not associated with decr eased flour yield. Puffing and shriveling scores were independent (poo rly correlated), but together predicted 95% of the variation in origin al, nonaspirated test weight.