Rheological properties of rice flour treated with mild solutions of citric acid.

Abstract

Effects of milling methods and organic acids treatments on rheological properties of rice flour were investigated. The average particle-size of wet-milled rice flour was lower and showed lower pasting temperature, peak viscosity, and storage modulus values than those of dry-milled rice flour. Wet-milled rice flour treated with citric acid showed significantly low viscosity and viscoelastic properties, as the concentration of citric acid increased, whereas wet-milled rice flour treated with acetic acid was not significantly affected by the acetic acid concentration. Rheological property of baekseolgi (Korean rice cake) made with wet-milled citric-acid-treated rice flour showed a similar trend in viscoelasticity, wherein citric acid treatment lowered the hardness of the rice. However, cohesiveness increased with increasing citric acid concentration. Overall, milling method affected the particle size, which influenced the viscosity and heat stability, whereas citric acid treatment affected the rheological properties of rice flour. These results are expected to contribute to the development of an appropriate method for rice flour application.