This study was performed to develop experimental model for milling degree and whiteness from analysis the CBB (colored bran balance) index using NMG dying and image processing. The endosperm layer increased and the pericarp, aleurone layer and CBB index decreased as the milling degree and whiteness increased. So, CBB index was closely linked to milling degree and whiteness. A empirical CBB index model was developed according to the milling degree and whiteness. The model were found to fit adequately to all test data with a coefficient of determination of 0.99, and therefore the CBB model proved to be quite applicable.