[Use of infrared radiations in the freeze-drying of foods (author's transl)].

Use of near infrared radiation as heating source in freeze drying of food products, appear to be interesting both for the efficiency of the process and for its economical aspect. In the present paper the results obtained in freeze drying runs with heating plates and I.R. radiations are described. The obtained results show that: with increasing trays load of product, the I.R. system is more efficient than the traditional one; the product quality obtained is higher for I.R. radiation, especially with higher tray loads; the heat flux output of the I.R. system is much lower than the one of the heating plates, at the same level of subliming water.