Effect of milling methods and varieties on the physicochemical properties of brown rice flours and eating quality of extruded rice noodles

The effects of different milling (dry, tempered dry and wet) methods and varieties ( indica and japonica ) of brown rice (BR) on the physicochemical properties of BR flours (BRF) and eating quality of extruded rice noodles (ERN) were investigated. Results showed that tempered dry- and wet-milled BRF showed smaller particle sizes, lower damaged starch (DS) content and water solubility index, as well as higher L∗ value and pasting viscosity. Under different milling methods, indica BRF exhibited lower DS content, better pasting properties. In addition, extrusion treatment promoted the transformation of insoluble to soluble dietary fiber in the ERN, which improved the nutritional value and taste of rice noodles. The ERN prepared with wet milling indica BRF showed lower broken stripe rate (1.67%), cooking loss (7.10%), and higher hardness (2433.73 g), demonstrating optimal product quality. Principal component analysis and correlation analysis showed that the particle size, DS content, and water absorption index of BRF were the key factors influencing the quality of ERN. These results provide a scientific basis for industrial production of BRF and ERN in the future.