Effect of steeping duration on nutritional properties, flavor, and starch digestive characteristics of quinoa-wheat composite bread

Whole wheat grains have gained significant market value owing to growing consumer demand for healthy diets. This study explored the effect of steeping treatment on quinoa bread production. The purpose was to both increase utilization of quinoa seeds and improve the quality of bread. Quinoa seeds were steeped for 0, 20, 40, and 60 min with other excipients and used to produce quinoa bread. This was tested for organoleptics, texture, color, nutrients, flavor substances, and in vitro starch digestibility. The results showed that steeping had no significant impact on macronutrient content but influenced color parameters and texture. Starch digestibility was affected, with increased rapidly digestible starch (RDS) and decreased resistant starch (RS) following extended steeping, though quinoa bread still exhibited a lower glycemic index (GI) than wheat bread. Volatile compound analysis revealed enhanced fruity and grassy aromas after steeping, significantly improving sensory scores. Steeping for 40 min yielded the best overall quality, effectively reducing bitterness while maintaining nutritional value and producing a desirable aroma and texture. Therefore, longer steeping duration can effectively improve the sensory quality, flavor, and nutritional characteristics of quinoa bread. • Longer steeping improves quinoa bread texture, color & sensory scores. • Steeping reduces bad flavors, enhances fruity/floral aromas in bread. • Starch digestibility increases with steeping; nutrients remain stable. • Quinoa bread offers lower starch digestibility than wheat bread (low-GI). • Steeping duration should be tailored balancing flavor, nutrition & digestibility.