Separation and identification of some synthetic food colorants from foods through thin-layer chromatography – “UV- VIS” Spectrometry

Authors:
Olivia Florena Măruţoiu, Ioan Gogoaşă, Constantin Măruţoiu, Maria Tofană, Diana Moigrădean, Iosif Gergen

Volume 17, Issue 1;
Pages: 46-53;
ISSN: 2069-0053 (print) (former: ISSN:1453-1399), Agroprint;
ISSN (online):2068 – 9551

A mixture of ten synthesis food colorants was separated on chromatographic plates with diatomitic n-octylsilane (C-8) and n-octadecylsilane (C-18) chemically altered diatomitic earth plates using as a mobile phase an absolute ethanol mixture – K2SO4 1% in water (40:60, v/v), and absolute ethanol – K2SO4 0.5% in water (40:60, v/v), respectively. Samples of non-alcoholic beverages with different colorants were evaporated to dry and the residue was dissolved in 0.5 mL ethylic alcohol and chromatographed together with samples on chemically altered diatomitic earth plates. Identifying synthesis colorants in foods was done on the ground of samples and through UV-VIS adsorption spectrometry after cutting out the spots and extracting the colorants in methanol-water.