The nutritional components and physicochemical properties of brown rice flour ground by a novel low temperature impact mill

A low temperature impact mill (LTIM) was created and used for grinding brown rice. The nutritional components and physicochemical properties of the resulting flour were investigated and compared with those ground by traditional wet colloid mill (CM) and dry high-speed universal grinder (HUG). It was found that LTIM produced a fine flour with unimodal particle size distribution, and well retained non-starch nutrients. Especially, the phenolic content of flour prepared by LTIM was two times higher than that prepared by CM. LTIM also led to less damaged starch content than HUG. The damaged starch content related well with the thermal and gel hydration properties. Interesting, comparing the particle size distribution before and after enzymolysis, it was found that LTIM could pulverize dietary fiber of brown rice efficiently. The results from this study indicated that the LTIM may provide a promising technology for pulverizing brown rice thus open its new applications.