Effect of different thermal treatments on flavonoids and quality traits of tartary buckwheat and its noodles

Abstract

Hydrothermal treatments can efficiently inactivate rutin-degrading enzymes (RDEs) in tartary buckwheat, albeit increasing moisture content. Stir-frying (SF) is a promising thermal processing. Thus, this study applied steaming in combination with oven-drying (S + OD), SF, roasting (R) and oven-drying (OD) to treat tartary buckwheat before noodles were processed with heated buckwheat flours. The flavonoid contents and quality traits of buckwheat and noodles were detected. All thermal treatments reduced noodle breakage and water absorption, S + OD, SF and R inhibited RDEs with lower quercetin and higher rutin, and S + OD had the best effect. S + OD and R enhanced the texture properties of noodles. Correspondingly, S + OD noodles had better textural and taste scores, and higher flavonoids and antioxidant ability, while R reduced total flavonoids and elevated noodles' a*, and SF noodles had inferior textural properties. Therefore, S + OD treatment could better retain total flavonoids and rutin contents of tartary buckwheat and its noodles and improve their quality traits.