Extraction of food synthetic dyes from aqueous solutions with liquid ion exchanger

Abstract

Synthetic dyes (SD) are widely used in modern food industry. According to the requirements of the Customs Union Technical Regulation, the content of SD is standardized, therefore, universal and express methods of analysis are needed. The main difficulty in determining them in food products is the separation from the matrix components such as proteins, fats, carbohydrates, anthocyanins. For this purpose, the extraction of commonly used synthetic food dyes from aqueous solutions using a liquid ion exchanger trioctylamine (TOA), dissolved in chloroform and toluene, was studied. Distribution coefficients (D) and recovery rates (R, %) were calculated. It has been established that TOA quantitatively extracts SD from aqueous acidified solutions, while they can be completely reextracted at pH > 8–9.