Continuous extrusion cooking of cottonseed kernels and of partially defatted meal

Continuous extrusion cooking produces a short time pressure cooking of the material in process. The Wenger extruder‐cooker has been successfully applied by others to soybeans for manufacture of full fat flour. This is a report of an investigation of the extruder‐cooker applied to glanded cottonseed kernels and to partially defatted cottonseed meal. The purpose was production of cottonseed flour for human food. The principal objective in extruder processing was lowering of free gossypol to 0.12% of protein. On full fat kernels the extruder system was effective in lowering free gossypol. Most of the binding occurred in the preconditioner, and the extruder itself was relatively ineffective in binding gossypol. However the contribution of the extruder was necessary to allow free gossypol levels of 0.12% of protein to be reached. Flaked kernels cooked in this manner and then dried were successfully screwpressed. The extruder system was effective also in binding gossypol in ground, screened (through 30 mesh) meal but not in ground, unscreened meal.