A process and system for preparing vegetable oilseed meal for subsequent solvent extraction of the contained vegetable oil, comprising a screwpress section and extruding/expanding section, a common worm shaft (10, 11) rotating within a perforated barrel wall section (14) and a non-perforate barrel wall section (18) connected by an annular member (16) with water injection nozzles (17) therein. Meal enters at inlet (13); oil is extracted through wall (14); the meal enters section (18) at increased temperature and moisture content; its temperature is then increased further to a level at which the increased moisture content will flash off as the meal leaves the restricted orifice (19) thus increasing the porosity and extractability of the meal.