Cereal Chem. 70:36-41   |  VIEW ARTICLE

Air-Aspirated Cleaning to Separate Sound from Preharvest-Sprouted Wheat.

A. D. Bettge and Y. Pomeranz. Copyright 1993 by the American Association of Cereal Chemists, Inc. 

An air-aspirated wheat cleaner fractionated two sets of preharvest-sprouted wheats (falling numbers 62-376) through the combined influences of aerodynamic drag, kernel volume, and kernel weight. One set was fractionated at a water column (WC) air pressure of 3.81 cm (1.5 in.); the other set was fractionated under WC air pressures of 2.54, 3.81, and 5.08 cm (1, 1.5, and 2 in., respectively). Each treatment resulted in a lifted fraction and a fraction passing through the air-aspirated cleaner. The fractions, plus the original grain, were analyzed for physicochemical, alpha-amylase, and end-use parameters. The first set of samples showed significant physical and physicochemical differences between lifted and throughs fractions. The improvements were most meaningful for wheats of moderate preharvest sprouting (falling numbers between 200 and 300). Throughs fractions produced better sponge cakes, in volume and texture, than the other fractions. The second set of samples exhibited a similar pattern: significant improvement in wheat of moderate preharvest sprouting but no meaningful improvements in either highly or lightly sprouted samples. Significant improvement was observed in fractions passing through the aspirator relative to the original and to the lifted fractions in samples of moderate preharvest sprouting. This improvement was most evident in the fraction passing through the aspirator at 5.08-cm WC air pressure. Aspiration at this air pressure causes about 50% of the sample to be removed.