Analysis of Food Colors by Thin-Layer Chromatography/Scanning Densitometry

Many synthetic and natural colors are used in foods all over the world. In Japan, 12 synthetic and 66 natural colors are generally permitted for use in foods. The Japanese government requires labeling on the package concerning kinds of colors that have been used in the contained foods. However, nonpermitted colors are also frequently detected in food, and also unlabeled foods are found in the market. Thus, the inspection of colors in foods has been performed by a public health agency.