Effects of spinach powder on the physicochemical and antioxidant properties of durum wheat bread

An adequate intake of dietary fiber in baked foods with appropriate physiological functions is beneficial to human health. The spinach powder (1, 2, and 3 g/100 g) was supplemented with refined wheat flour to investigate its effect on physicochemical and antioxidant properties of bread. The mixing, pasting, and rheological properties of dough, as well as physical, antioxidant, and sensory properties of bread were analyzed. Results showed that water absorption%, stability and development time, protein weakening, and starch crystallinity of spinach samples increased to 62.40%, 5.92/min, 2.05/min, 0.76 Nm, and 0.21 Nm. The peak viscosity, final viscosity, setback, and breakdown values were significantly decreased to 2205.71, 2485.05, 1122.74, and 843.36 cP, respectively. Samples exhibited the highest elastic (218017 Pa) and viscous (94257.76 Pa) moduli and the lowest specific volume (3.12 cm3/g), color attributes, and sensorial properties. Furthermore, breads stored for different periods showed the minimum hardness (4151.67 N), chewiness (826.33 N), and resilience (0.08) compared to control. In addition, the 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power, and 2,2 '-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid properties were also significantly improved in corresponding samples. Findings suggest that incorporating spinach into wheat flour could be a viable approach to produce healthy bread enriched with fiber, protein, and antioxidants.