Identification and quantification of sodium benzoate in soft drinks available in Tangail region by high-performance liquid chromatography

Abstract

Sodium benzoate is a permitted food additive by international laws in processing restrictive amounts, but its content must be declared and must not exceed the established limits by legislation. An experimental study was performed by high-performance liquid chromatography (HPLC) for determining the level of sodium benzoate in different brands of soft drinks available in the markets, stores, and shops in the Tangail region of Bangladesh. A Luna 5 µ C18 (2) 100A column (250×4.6 mm) was used for the chromatographic analysis. Chromatographic separation was achieved with an isocratic solvent system comprising sodium acetate and acetic acid buffer (pH = 4.0)/acetonitrile in the ratio of 80:20 (1 mL/min) at 37oC and the chromatograms were recorded at 254 nm. The limit of detection and quantification for sodium benzoate was 0.0000493 mg/100 mL and 0.000149 mg/100 mL, respectively. Quantification of the selected brand soft drinks revealed that the level of the used sodium benzoate was within the FDA standard range. However, by comparing with the Bangladesh Standard and Testing Institute (BSTI), brand -2 and brand-3 soft drink samples were found to exceed the current legal limits.