1994 Volume 48 Issue 6 Pages 421-426
Dyes in pickles are extracted from aqueous solutions as ion-pairs with a series of amine such as tri-n-octylamine (TOA), tri-iso-octylamine (TiOA), di-n-octylamine (DOA), and tri-n-hexylamine (THA) in chloroform. The influences of pH and the concentrations of sodium chloride and the amines on the extraction were examined. The equilibrium is attained in 2 min or less. The extractability of amines for tartrazine was in the order TOA>THA>DOA>TiOA. Tartrazine, sunset yellow and sorbic acid are separated from pickles by elution with aqueous ammonia system. The extract was purified by ion-pair extraction with TOA, and the dyes and sorbic acids were analyzed by high-performance liquid chromatography. The detection limits were approximetely 2.0, 1.0 and 0.5 μg cm-3 for tartrazine, sunset yellow, and sorbic acid, respectively.