Effects of adzuki bean addition on the rheological properties of mixed flour and the in vitro digestion of rice noodles

Adzuki beans are rich in phenols and flavonoids, which are of great significance for the nutritional supplementation of rice noodles. However, how to control the amount of Adzuki beans added to meet the rheological properties of rice noodles is unknown. Herein the effects of adzuki bean addition (0 % – 50 %) on the rheological properties of rice flour and the qualities of corresponding noodles were investigated. It was revealed that adzuki beans reduced the viscosity, gelatinization enthalpy, storage modulus ( G' ) and loss modulus ( G" ) values of the mixed flours. The resistant starch content increased from 23.74 % to 44.67 %, and the predicted glycemic index (pGI) decreased from 80.24 to 54.81. Adding 20 % adzuki beans had a minor impact on sensory quality while reducing pGI. Adzuki beans weakened the ability of starch to bond with water molecules, but shortened the optimal cooking time and quickly restored the elasticity of rice noodles.