Studies on separation and determination of subsidiary colors, raw materials and intermediates in food yellow no. 5 (Sunset yellow FCF) by HPLC

Abstract

Separation and determination of subsidiary colors, raw materials and intermediates (organic impurities) in commercial Food Yellow No. 5 (Y-5, sunset yellow FCF) were studied under various HPLC conditions. Separation of the trisodium salt of 7-hydroxy-8-[(4-sulfophenyl)azo-1,3-naphthalenedisulfonic acid (SA-G) and the disodium salt of 4,4′-(diazoamino)dibenzenesulfonic acid (DAADBS) was established by HPLC using L-column ODS and a gradient system of 0.02 mol/L ammonium acetate solution (after isocratic elution for 10 min as a first step) and a mixture of acetonitrile and water (7:3). The organic impurities in 39 samples of Y-5 submitted for the inspection in fiscal year 1998 were determined using the proposed HPLC conditions. It was found that the total amount of subsidiary colors in the samples was less than 1/5 of the permitted limit, and the total amount of raw materials and intermediates was not more than half of the limit.