Development of functional couscous samples with high β-glucan content and low or medium glycemic index

Abstract

This study presents the development of functional couscous enriched with β-glucan through incorporation of a high β-glucan hull-less barley (cv. Chifaa), into durum semolina. Four couscous samples were prepared using 100% cereals (from Chifaa hull-less barley; Svevo, Svevo High Amylose, and Faridur durum wheat varieties), and three samples were obtained as 50:50 wheat–barley blends. Comprehensive analysis included color, chemical (β-glucan, resistant starch, protein), antioxidant (DPPH, ABTS, FRAP), textural (hardness, chewiness, cohesiveness, resilience), and nutritional (in vitro glycemic index (GI)) properties. Chifaa couscous displayed the highest β-glucan (6.49 g/100 g dry basis), phenolic content, antioxidant capacity, and the lowest GI (53.56), classifying it as a low-GI food. All 50:50 blends with Chifaa exceeded 0.75 g β-glucan/serving (which is 157 g according to USDA’s FoodData Central), meeting FDA health claim requirements. Incorporation of Chifaa improved cohesiveness and chewiness. High-amylose wheat (Svevo HA) additionally contributed to resistant starch content, further enhancing health functionality. These findings highlight the potential of hull-less barley in producing functional Mediterranean-foods that meet regulatory standards supporting dietary strategies for glycemic control and cardiovascular health.