Tomato paste is a highly concentrated tomato processing product, widely used in the food industry as a semi-finished product for the production of sauces, ketchups, canned goods, and a wide range of other food products. A promising area for improving tomato paste drying technology is foam drying using infrared (radiation) energy supply, which allows for intensifying the moisture removal process and preserving the quality of the finished product. A solution of ichthyogelatin, a biopolymer obtained from fish processing waste, has been proposed as a foaming agent and foam stabilizer. Rational implementation of convective-radiation foam drying requires a comprehensive study of the optical and thermoradiation properties of the dehydrated material. This paper presents the results of a study of the optical and thermoradiation characteristics of a foam layer of tomato paste with the addition of a solution of ichthyogelatin as a foaming agent and stabilizer. The absorption of infrared thermal energy by an optically thin product layer (h ≤ 0.004 m thick) in the humidity range of 0.10 ≤ w ≤ 0.78 kg/kg was examined when irradiated with various radiation generators: a quartz halogen tube, a nichrome coil, a metal plate, a gas infrared radiation plate, and a tubular electric heater. The experimental and analytical studies were performed using a Varian Cary 5000 UV-Vis-NIR spectrophotometer with a DRA-2500 integrating sphere attachment in the spectral range of 800 ≤ λ ≤ 2500 nm. The dependences W=f(x,w), W/m³ of the distribution of the volumetric density of absorbed radiant energy by the depth of an optically thin foam layer with a volumetric (two-sided) supply of heat flow to the product with a total density of E=1680 W/m² were obtained. Based on the analysis of the obtained dependences, as well as a comparison of the emission characteristics of the radiation generators and the spectral transmittance of the foam layer, the feasibility of using quartz halogen tubes at 220V was confirmed to ensure the most uniform distribution of absorbed energy across the layer depth throughout the moisture removal process. The obtained dependences are applicable for subsequent modeling of transient temperature fields in the product during the foam drying process of tomato paste with convective-radiative energy supply

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