BREAKAGE SUSCEPTIBILITY of SHELLED CORN DUE to REHYDRATION and REDRYING

ABSTRACT Processing activities such as drying expose grains to temperature and moisture gradients resulting to increased susceptibility of corn breakage. the effect of rehydration and redrying rates on the breakage susceptibility of corn was compared and evaluated. Dried corn samples were rehydrated and redried artificially. Breakage susceptibility of the samples were tested using a food grinder (blender) and Instron testing machine. Treatments consisting of a cycle of rehydration and redrying represented different rates of moisture sorption. Initial sample moisture, rehydration methods and redrying temperatures were used in comparing breakage susceptibility. Samples of low initial moisture had higher breakage susceptibility as compared to higher initial moisture samples. the rehydration method representing the highest moisture adsorption rate resulted to samples which were more susceptible to breakage than the two rehydration methods representing intermediate and slow rates of moisture adsorption. Temperature of redrying also showed significant effects with high temperatures (80°C) resulting to grains with higher breakage susceptibility compared to samples redried with unheated air (30°C). Breakage susceptibility increased when samples were rehydrated and increased much more when they were redried.