Survey of canthaxanthin content in commercial chicken eggs sampled from Hunan province, China

Abstract

Canthaxanthin (Cx) is a feed additive widely used for pigmenting egg yolk. In this study, a ultra performance liquid chromatography (UPLC) method was used to detect Cx in commercial chicken eggs sampled from Hunan province, China. Results showed that 43.75% of samples (14 out of 32) possessed detectable amount of Cx, ranging from 0.8 ± 0.2 µg/g to 152.8 ± 10.4 µg/g, and 25.0% of samples (8 out of 32) carried residues of Cx at levels higher than the approved maximum residue limit (MRL = 30.0 µg/g). Interestingly, higher detection rate and above-MRL rate were reported in samples that claimed to be free-range eggs and were collected from traditional farmers’ markets. This survey illustrates that Cx might occasionally be used in excess for breeding hens, in the surveyed area, especially in those that are not branded. Therefore, more strict regulatory measures are urgently required to be taken up by the Chinese government to retain the safety of chicken eggs and to ensure that consumers are not deceived by the color of yolks pigmented with Cx.