The effects of high-protease activity flour (HPAF) on cookie quality were investigated comparing two proteases (Protease 1 and Protease 2). The commercial proteases and HPAF were added to wheat flours (cvs. Gerek and Gun) with different gluten quality at levels of comparable protease activity. Electrophoresis was used to determine the hydrolyzing effects of the proteases on gluten proteins. Cookies were prepared with wire-cut formulation and quality parameters (spread ratio and color values) were determined. Electrophoresis results showed that degradative effects of Protease 1 and Protease 2 were more evident on gliadins and glutenins, respectively. Protease 2, added to cookie formulations for both wheat samples, gave the highest spread ratios. For the strong wheat cultivar (Gun) spread ratio values of the cookies supplemented with HPAF were comparable to those supplemented with Protease 2. (c) 2004 Elsevier Ltd. All rights reserved.