It is the leftover fragment of rice kernel separated from the larger kernels of milled rice. (pawdiet.com)
While milled rice kernels are only about one half to two thirds the original size of the whole kernel, brewer's rice grains are about one quarter the size. (dogfoodinsider.com)
The traditional method of making red yeast rice is to ferment the yeast naturally on a bed of cooked non-glutinous whole rice kernels, and this method has been industrialized for production in the United States. (bio-alternatives.net)