Old and modern durum wheat genotypes were compared to understand the impact of breeding on gluten and dietary fiber composition. Modern wheat had higher gluten quality due to increased glutenin and LMW-GS content, while old wheat had lower allergenic ω-5 gliadins. Water deficit during grain filling affected gluten protein composition. Modern wheat had more soluble arabinoxylan, while old wheat had lower arabinose:xylose ratio in semolina. Modern wheat had higher β-glucan content in semolina. Viscosity of soluble dietary fiber extracts varied among durum wheat genotypes. No significant differences were found in bound phenolic acids between old and modern genotypes.