Abstract: The present invention pertains to a process for the thermal, thermomechanical, hydrothermal or hydrothermomechanical treatment of various natural or transformed alimentary, cosmetic, chemical or pharmaceutical products, in solid, piece, powder, paste, liquid, miscible or nonmiscible liquid mixture, etc. form comprising the precise control of multiple classic thermal processes by accelerating the kinetics, improving the quality of the finished products and reducing the energy consumption and reject rate. These processes generally pertain to the operations of pasteurization, sterilization and/or packaging of solid products in piece or powder form, the thermal modification of the materials (gelatinization, for example), their structure and/or their texture, or the separation of their compounds. The process which is the object of the present invention comprises a step for heating the products to be treated and is characterized by a cooling step based on a pressure drop to vacuum after the heating step.