ABSTRACT. Textural properties of extruder cooked soybean and cottonseed flours were evaluated by a tasting panel and ultrastructure study. An attempt was made to correlate the findings of the tasting panel with chemical and physical parameters. The role of NSI in the flours and the size of the texturing machinery (X‐5 vs X‐25 or laboratory vs plant size) were evaluated as well. Water absorption and integrity tests values of the cottonseed products were lower than those of soybean. The free gossypol values of the cottonseed extruded products are relatively very low. Significant differences were found between the ultrastructure of the soybean and the cottonseed extrudates. Several stages of induced texturization of cottonseed protein were observed by the electron microscope while soy proteins had only one.