Determination of Food Preservatives in Drinks by Dispersive Liquid-Liquid Microextraction Coupled to Capillary Gas Chromatography

Abstract

This study describes an analytical method employing capillary gas chromatography (GC) using flame ionization detection (FID) that has been developed for the simultaneous determination of food preservatives in drinks, including sorbic acid (SA), benzonic acid (BA) and methyl paraben (MP). For this purpose, dispersive liquid-liquid microextraction (DLLME) was applied as a sample preparation technique. The DLLME conditions such as the types and volume of extraction solvent, the types and volume of the disperser solvent, pH value and salt addition were investigated and optimized. The method was linear in the ranges from 0.5 to 100.0 μg·mL-1for abovementioned preservatives withR2≥ 0.9991. The DLLME procedure allowed efficient recovery of the analyted preservatives ranging between 91 % and 108 % with a relative standard deviation (RSD) ≤ 6.1 for the blank samples spiked with 20, 40 and 80 μg·mL-1of preservatives, respectively. The developed procedure was demonstrated to be a effective method for the analysis of preservatives in drinks. Furthermore, the method is simple, reproducible, envioronmentally friendly and inexpensive.