Measurements of Accompanying Air, Specific Surface Area and Micropore Volume of Some Flour Particles

Abstract

The volume of air accompanying flour particles was determined through the measurement of the apparent density and compared with the volume of micropores, smaller than 30 nm in diameter, of the flour particles, which was measured by the Cranston-Inkley method. Weak wheat flour had the largest amount of accompanying air, strong wheat flour an intermediate amount, and rice flour the least. Most of the air accompanying the wheat flours was held in pores larger than 30 nm in diameter, while most of the air accompanying the rice flour was held in pores smaller than 30 nm in diameter. From the viewpoint of the expansion of dough, the condition of the wheat flours was much better than that of the rice flour.