INTERNAL DAMAGE TO WHEAT-GRAIN AS A RIDSULT OF WETTING AND DRYING

Processes of heat and mass exchange which take place in the course of wetting and drying of cereal grain cause internal stress, the result o f which are endosperm cracks. This damage, invisible to the naked eye and difficult to detect, causes specific effects, physical as well as biological. Spring wheat grain, cv. Henika, of an initial moisture con tent of 10% and varied endosperm structure (vitreous and mealy), was s ubjected to the process of wetting, and then dried under various therm al conditions. Internal damage to grain, caused by those processes, wa s detected by means of X-ray techniques. The extent of damage was desc ribed by means of suitable numerical indexes. Analysis of the results obtained revealed that, irrespective of the methods of grain treatment (wetting or drying), vitreous kernels suffered more extensive damage than mealy ones. The most extensive destruction of endosperm was obser ved following the drying of grain of high moisture content at high tem perature. Copyright (C) 1996 by Marcel Dekker, Inc.