Abstract
Since heating by infrared radiation can heat directly liquid food, the surface of the food becomes a high temperature, and stainless steel plate which has contacted the food would be maintained a low temperature. As a result it seems to be able to reduce the adhesion of the fouling in the stainless steel plate, which was an important problem in the conventional heat exchanger. In this study we developed the continuous heating equipment using far-infrared radiation, and verified that this system is practically available to pasteurization. In this developed equipment, the liquid food flows down as a thin liquid film, because the penetration of radiation energy to the water is low and the heating of the liquid inside is difficult. Using this equipment, increased temperature of the sample was measured by changing the heating conditions such as supplied electricity to the heater and the liquid flow conditions such as flow rate. The result showed that the increased temperature rises, as liquid film thickness thins, and that the sample temperature could be heated to about 80°C. Using lactic acid bacteria and yeast, the pasteurization experiments were performed. As the result, the death of the bacterium and the yeast could be confirmed, and the effectiveness of this equipment could be verified.
