Abstract
The effect of the penetration of infrared radiation energy into food on the temperature was studied. Model foods of 1.2% agar gel, 1.2% agar + 5% cornstarch gel and fish paste were each irradiated by a halogen heater and two types of ceramic heater. The transient temperature and the temperature profile near the surface of each food model were measured. The experimental results and the thermal diffusivity of a sample were used to estimate the radiation energy applied to the food. The halogen heater affected the heat transfer in the range of 1-3 mm below the surface, while the ceramic heater had no effect deeper than 1mm. It was found that the penetration of near-infrared radiation energy was deeper than that of far-infrared energy, and that increasing penetration accelerated the temperature rise within the food sample.
