Effect of quinoa flour on baking performance, antioxidant properties and digestibility of wheat bread

[Display omitted] •Wheat bread (WB) containing quinoa flour (QF) exhibited slower aging rate.•With increasing QF addition, WB showed increased antioxidant activity.•With increasing QF addition, WB demonstrated lower estimated glycemic index.•QF could disrupt gluten network, causing discontinuous or even fibrous gluten network.•QF changed gluten secondary structure, causing more random coil and inelastic β-sheet. Quinoa flour (QF) was added in wheat flour to make nutritionally fortified wheat bread (WB). Effects of QF on baking performance, antioxidant activity and digestibility of WB were studied. The results indicated that with an addition of a small amount of QF (5%) would not affect the baking performance of WB, while higher amounts of QF (10% and 15%) resulted in smaller specific volume, increased hardness and coarse porosity, since QF changed gluten secondary structure and disrupted gluten network. However, sensory evaluation showed that the flavor of WB enhanced significantly with increasing QF addition. More importantly, WB containing QF exhibited improved antioxidant activity and reduced in vitro digestibility with lower estimated glycemic index (eGI) and higher content of slowly digestible starch (SDS) and resistant starch (RS). Our findings indicate that QF-fortified bread is promising to be developed as a functional food with relatively lower eGI and more effective antioxidant properties.