Drying and texturation of strawberry by Controlled Instantaneous PressureDrop and air drying. [French]

摘要

To obtain new dehydrated products (dried and crisp products) for varied applications in confectionery or instant foods, the texturation process by Controlled Instantaneous pressure Drop (DIC) has been applied to strawberries drying. This operation is based on mechanical effect and heating treatment in three steps. Firstly, products are air dried until a precise moisture content. Then, they are submitted to heating under high pressure followed by a quasi-instantaneous pressure drop into vacuum causing their puffing and texturation by partial self-vaporization of water. Finally, air drying brings products to a low moisture content. The quality of final products is quantified as to the structure (expansion rate), the aptitude to the technology (reduction of final stage of drying) and the functional properties (speed and capacity of rehydration). Effects of three DIC operating parameters (treatment pressure, treatment time and product moisture content) have been analysed by experimental design. The results of this statistical study will help to find an optimal combination of these operating parameters for strawberries drying and texturation.