Rapid quantitative method for total brominated vegetable oil in soft drinks using ion chromatography

Abstract

A simple, quantitative and rapid method for total brominated vegetable oil (BVO) using ion chromatography (IC) with suppressed conductivity detection was developed and successfully applied to soft drinks with results expressed as inorganic bromide anion. The procedure involves extraction of BVO with diethyl ether and treatment with zinc dust in a solution of acetic acid, giving recoveries ranging between 92.5 and 98.5%. The calibration curves obtained were linear with correlation coefficients (r ²) of 0.998, a coefficient of variation (CV) of less than 5% and limit of detection (LOD) and limit of quantification (LOQ) of 250 and 750 µg l⁻¹, respectively. The method was successfully applied to the determination of BVO in several commercial soft drinks which were found to contain BVO in the range 1.8–14.510 mg l⁻¹. The method has less sources of error compared to previously published methods.

Keywords:

• chromatographic analysis
• health significance
• method validation
• screening assays
• bromate
• fluoride
• food simulants
• beverages
• fruit juices

Acknowledgements

The authors thank the management of the Public Health Department, Ministry of Health, Kuwait for their support and our colleagues in the Food Chemistry Unit for their co-operation.