Hygroscopic parameters of gelatin from fish processing waste

We studied the hygroscopic properties of gelatin from waste-products after processing common fresh-water fish species form Astrakhan region (skin, scales, bones, fins, and cartilage) as an object drying. The analysis thermodynamics internal mass transfer was carried out during interaction substance specified product with water. objects study were concentrates obtained by convective-radiation drying granules, previously foamed to a constant expansion ratio cooled gelatinization temperature. studies experimentally analytically using tensometric method Van Bamelen. For thermodynamic characteristics, classical Gibbs–Helmholtz equation used. On basis empirical data, sorption isotherms – functional dependences level water activity Aw on equilibrium moisture content temperature product. are S-shaped, typical for colloidal capillary-porous bodies, which is due foam structure curves can be conventionally subdivided into three zones, corresponding monomolecular polymolecular adsorption, structural, microcapillary, microcapillary moisture. Based under study, determined its various temperatures: Wg1 = 0.280 kg/kg T 283 K Wg2 0.301 303 K. threshold range states important point view rationalization modeling heat material dehydration. As result calculations equation, free, bound, energy well total specific thermal evaporation derived. It has been established that nature these samples generally consistent published data number materials biopolymer nature. These dependencies used in development dehydration processes design equipment production waste.