Determination of Synthetic Colors in Meat Products Using High-Performance Liquid Chromatography with Photodiode Array Detector

Abstract

Synthetic colors are a substance, liquid or powder, which are added to foods to replace natural color lost during processing. A rapid and simple method for simultaneous determination of seven synthetic colors such as amaranth (E123), ponceau 4 R (E124), sunset yellow (E110), allura red AC (E129), red 2 G (E128), carmoisine (E122), and erythrosine (E127) in meat products using the technique of high-performance liquid chromatography (HPLC) with photodiode array detector is described. The sample is extracted with mixture of methanol and ammonia (80:20 v/v) in ultrasonic bath, and then the extract is filtered through a glass filter paper. Synthetic colors were determined by reversed-phase liquid chromatography using a C₁₈ column and a photodiode array detector. Synthetic colors were separated using HPLC/diode-array detector method on 250 × 4 mm I.D LichroSphere RP-18endcapped column (Merck, Darmstadt, Germany) with 5 µm C₁₈ stationary phase, and the chromatograms were detected at 500 nm. Acetate buffer (pH 4.8) and acetate buffer (pH 4.8) with acetonitrile (40/60 v/v) were used as the mobile phase, and the flow rate was 1.0 mL min⁻¹. Satisfactory recoveries, ranging from 77.0% (erythrosine) to 99.5% (sunset yellow), were obtained. The method was useful over a wide concentration range of synthetic colors. Synthetic colors as low as <0.1 mg kg⁻¹ and as high as >500 mg kg⁻¹ in various meat products could be detected easily without any noticeable disadvantage. The limit of detection and the limit of quantification of individual synthetic dyes were 0.05 mg kg⁻¹ and 0.1 mg kg⁻¹, respectively.

Keywords:

• HPLC
• meat products
• synthetic colors
• trace analysis