Abstract
This article reports on a method to determine synthetic dyes in yogurts and milk drinks. Initially a method for extraction of artificial dyes was developed to pretreat samples in order to extract most of the artificial colorants. Then, the colorants were analyzed by HPLC–PAD using gradient elutions. The method was linear in the range of 0.5–25 mg L−1 colorants (0.9991 < R2 < 0.9998), with LOD of 0.18–4.58 μg L−1. The results recovery test on two levels ranged from 82% to 115%. The reference solution of the analytes remained stable for 3 months. In the yogurt samples analyzed, the dye E122 (1.4–11.75 mg L−1) was found in most samples, followed by dye E123 (3.12 and 12.56 mg L−1). All samples had concentrations below the maximum level allowed for use in yogurt (100 mg/100 g dyes).