2003 Volume 65 Issue 2 Pages 64-70
The effects of infrared radiation on the microorganisms on wheat and soybean surface were investigated. Infrared radiation was an effective method to reduce the viable counts of these microorganisms in a short time. It appeared that the internal quality of cereal grains would be preserved since the intermittent irradiation could avoid high temperature of cereals surface, and reduce the viable counts effectively same as continuous irradiation. Moreover, it was estimated that the main mechanism of the sterilization by infrared radiation applied to these cereal was not the heat transfer by thermal conduction between the cereal surface and microorganisms, but the direct heating to these microorganisms by thermal radiation, because the surface temperature of wheat was 50°C higher than that of soybean by the irradiation of 7s.
