The GB 12097-1989 standard specifies a method for measuring the whiteness of starch using a light reflection whiteness meter, which is suitable for refined starch dried into powder. The whiteness of the sample is determined by comparing the reflectance of the sample and the standard whiteboard to blue light. The standard requires the use of a whiteness meter with a wavelength adjustable to 425nm, and the accuracy of the instrument needs to be ensured. The sample needs to be well mixed. The whiteness value is expressed by the arithmetic average of the two determinations. The allowable difference of the results does not exceed 0.2. This method provides an objective measurement standard of starch whiteness, which helps to ensure the conformity and mass of the product.