Effect of microwave heat processing on nutritional, antioxidant, antinutrient, and sensory indices of soy flour enriched functional noodles

Soybean is considered a plausible carrier of health-promising potential phytonutrients; the soybean also contains higher magnitudes of antinutrients like tannins, phytates, trypsin, protease, and oxalates. Therefore, the present study was carried out to reduce the load of antinutrients using microwave (Mw) heat processing at 0.9 kW for 1.5 min, also assessing its effect on soy flour's nutritional, antioxidant, and value-addition properties. Results for nutritional composition of raw soy flour (RSF), microwave heat processed soy flour (MwSF) and supplemented noodles delineated the presence of higher ash (3 %), dietary fibers (6.1 %), proteins (42 %), Zn (3.5 mg/100g), Ca (238 mg/100g), Mg (208 mg/100g) and K (355 mg/100g) in MwSF then RSF. However, MwSF supplemented noodles prepared at 2–6% supplementation levels (T 1 -T 3 ) elucidated significant ( p < 0.05) improvement in ash (0.7–1.1 %), fiber (3.7–4.1 %), crude protein (10–17 %), Zn (3.6–3.8 mg/100g), Ca (39–50 mg/100g), Mg (134–139 mg/100g) and K (440–446 mg/100g). Processing of raw soy flour by microwave heating was observed to reduce tannins, phytates, trypsin, protease, and oxalates by 88, 87, 93, 95, and 90 %, respectively. The maximum supplementation of MwSF at 6 % in the supplemented noodles significantly ( p < 0.05) improved the total phenolic contents (TPC), total flavonoid contents (TFC), ferric reducing antioxidant power (FRAP), and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) from 131 to 142 mg GAE/100g, 52–57 mg GAE/100g, 217–233 μmol/100g and 37–40 %, respectively. Organoleptic evaluation of MwSF-supplemented noodles suggested the highest sensory acceptability at ≤4 % supplementation level (T 2 ). The study also suggests microwave heating as a viable approach to improve value-added goods' nutritional and antioxidant potential with the least safety concerns. • Microwave heating significantly reduced antinutrients in soy flour & MwSF noodles. • MwSF & supplemented noodles revealed higher proteins, fibers, Ca, Mg, Zn & K. • MwSF-supplemented noodles showed better cooking qualities & sensory attributes. • MwSF may anticipate better techno-functional attributes in soups, gravies & curries.