Determination of Synthetic Colors in Selected Market Foods in Macedonia By Reversed-Phase High Performance Liquid Chromatography With UVVisible Diode-Array Detection

Abstract

Food colors are commonly used in processed foodstuffs to improve their appearance and they have always had an important impact on people's minds as far as food is concerned. The Macedonian Food and Veterinary Agency imposed limits of concentration for food colors in different foods in Macedonia (Act on Additives Used in Food Production, 114/2013). The subject of analyses was determination of synthetic colors concentration in fifty samples of four different foods in Macedonian market: carbonated drinks, hard candy, yogurt and ham. The determination was performed of eight synthetic food colors: Tartazine (E102), Carminic acid (E120), Ponceau 4R (E124), Sunset yellow (E110), Allura red (E129), Carmoisine (E122), Curcumnie (E100) and Quinoline yellow (E104). Samples were analyzed by Reversed-phase high performance liquid chromatography (HPLC) with UV-visible diode-array (DAD) detector (Agilent 1260 Series, USA). Chromatographic conditions: mobile phase (composition and flow-rate) were evaluated and optimized in EC-C18 3 x 150 mm, 2,7 mmcolumn (Agilent, USA). Two different mobile phase systems with gradient elution method were employed to accomplish a quick separation of the analyzed dyes. Mobile phase A consisted of phosphatic buffer c(Na2HPO4) = 0,01 mol/L, pH = 7and mobile phase B consisted of methanol for HPLC. A constant flow rate of 0.6 mL/min was used, while the run time was 30 min.Limit of detection (LOD) for all matrix was 0,1 mg/l, limit of quantification (LOQ) 1 mg/L and accuracy and precision was between 94,2 and 109,3%. The results of all the analyzed samples were found below the Macedonian legislation limits for color additives in food. We can conclude that the HPLC-DAD is a suitable method for quantitative analyses or screening of food samples for synthetic food colors.