CHANGE IN VIABILITY OF MAIZE DURING HIGH-TEMPERATURE DRYING

Abstract

Germination and moisture content loss data were collected of maize with a moisture content ranging from 15 to 32% (w.b.), an air temperature from 40 to 75°C, and an exposure time from 0.5 to 180 minutes. A germination-retention model was developed based on the normally distributed death-rate theory (NDD). The NDD model was combined with a concurrent-flow (CCF) dryer model, and tested against viability data of maize dried in a commercial two-stage CCF dryer. Acceptable agreement between the predicted and experimental viabilities was obtained. The effect of the CCF dryer design, and of several operating parameters, on the loss of maize-seed viability was analyzed. Simulation with the NDD-CCF dryer model shows that high quality seed can be produced by drying at air temperatures well above 100°C.