Effect of malting conditions on phenolic content, Maillard reaction products formation, and antioxidant activity of quinoa seeds.

In this study, the effect of malting process on the antioxidant compounds and antioxidant capacity of quinoa seeds was studied. The optimal germination conditions were germination temperature of 23 °C, degree of steeping of 36% and germination time of 3 days. Under these conditions, green quinoa malt was obtained and subsequently roasted at different temperatures (100-190 °C). Results showed maximum increases in phenolic compounds, Maillard reaction products and antioxidant activity (DPPH radical scavenging and reducing power) in samples roasted at 145 °C for 30 min, whereas a more intensive thermal treatment (190 °C) diminished the levels of all evaluated variables. Thus, malting with a moderate thermal treatment could be considered as an effective process to enrich antioxidants in quinoa grains for their further use as functional ingredient in the production of gluten-free foods and beverages.