Microwave food processing for bioclean room patients.

In order to establish an efficient way to prepare diets for patients in bioclean rooms, sterilization and temperature increase of food and drinks were studied by means of a specially designed microwave oven, which can be set over a range of 50 to 600 W. It is built into a wall between the bioclean room and the preparatory room and can be opened from both sides. Tests were conducted on individual dishes and on Differential Heating Container (DHC) diets in which an entire meal is served on a single compartmentalized dish. The results showed that DHC diets can be completely sterilized and yet retain their tastefulness when subjected to 500 W for 15 min, even Escherichia coli and Bacillus subtilis have been added before the treatment. Although similar sterilization was attained with the individual dishes, use of the DHC system greatly reduced the time and effort for diet preparation. This microwave sterilization procedure was also effective for the special high-calorie powdered food E-651 which is often given in liquified form to patients who cannot accept solid food.