The influence of durum wheat cultivars, protein content, semolina granulation, and processing conditions on couscous quality was investigated. Homemade agglomerated couscous was prepared from each durum cultivar.;Single-screw extrusion as commonly used to process pasta products and high temperature, short-time (HTST) twin-screw extrusion cooking also were evaluated to determine whether couscous could be made, using extrusion technology. Results of the homemade couscous indicated that the strong gluten cultivars had an advantage over the weak gluten cultivars, particularly with respect to couscous yield and water absorption index (WAI). Fine semolina granulation had a negative effect on couscous yield and stickiness and a positive effect on couscous brightness and rehydration time. As protein quantity increased, semolina absorption, couscous yield, and cooking quality improved.;Couscous processed with a pasta extruder (cold-extruded couscous) was highly compact and showed poor cooking quality, characterized by long cooking and rehydration times. Blends of farina with semolina also were evaluated in this portion of the study, and this couscous was found to have poor color and cooking quality. As drying temperature was increased from 45;Couscous quality was found to be significantly improved with the HTST twin-screw extruder, compared to the agglomerated product (homemade and commercial) and the cold-extruded product. Product color, particle size uniformity, starch gelatinization, and steam cooking quality were significantly better when made with HTST extrusion. Using response surface methodology, acceptable HTST extrusion conditions for the production of a bright yellow couscous product with maximum starch gelatinization, high WAI, and low stickiness were found to range from 110
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