Effect of Fluorescent Light on the Isomerization of Retinyl Palmitate in Skim Milk

Abstract

ABSTRACT Skim milk fortified with retinyl palmitate was exposed to fluorescent light and analyzed for the isomers of retinyl palmitate. High performance liquid chromatography was used to separate and identify the all‐ trans and some cis forms. Besides all‐ trans retinyl palmitate, small amounts of 13‐ cis retinyl palmitate were present in unexposed skim milk. The level of all‐ trans decreased over the 48‐hr period of light exposure. The 13‐ cis levels also decreased but not as rapidly. The level of the 9‐ cis isomer increased over the 48‐hr period of light exposure.