The effects of gluten addition, dough moisture content and mixing time on the textural properties and in vitro starch digestibility of durum wheat bread made with coarse semolina

• Coarse semolina (> 1000 µm) needs a long mixing time (45 min) for dough development • Bread made with 100% coarse semolina was hard with low cohesiveness • 20% gluten in substitution of coarse semolina increased the overall bread quality • 20% gluten in substitution of coarse semolina decreases the overall starch digestibility The production of bread using coarse semolina (CS), rich in intact cells, was hypothesized to be a good strategy for limiting starch accessibility. However, during long mixing, cell wall porosity increases and CS presence decreases bread cohesiveness, leading to high starch accessibility. To address this, the effect of water absorption level (WA, 70 or 55%), mixing time (3.5 or 45 min), and the use of 100% CS (> 1000 µm) or its 20% substitution with gluten on the textural properties and in vitro digestibility of bread were studied. Bread made with 100% CS at 55% WA was the hardest, with low volume and less rapidly digestible starch (RDS). Gluten addition increased volume and porosity, leading to more RDS but reduced starch digestibility over time due to better structural integrity. These findings suggest that replacing 20% of CS with gluten could be an effective strategy to decrease starch digestibility while maintaining a porous structure.