Potential adaptation of GC-EI-MS method to determine the residue of natural EOs in eggs

Natural essential oils (EOs) are employed as efficient natural red mite repellents in egg production. EO residue in eggs and the method for detection are rarely discussed in the literature. This study presents an adaptation of GC-EI-MS method to identify and quantify the residue of EOs in eggs laid by in feed EO-supplemented hens, for 10 months compared to eggs from unsupplemented hens. 2 major aromatic compounds, geraniol and eugenol, originated from Cymbopogon nardus and Eugenia caryophyllus EOs respectively, were targeted.

This protocol was adapted based on the GC-EI-MS method developed by X. Li et al.,2019 [1]. Briefly, raw white and yolk were taken for analysis. Frist, acetonitrile (ACN) was used for protein precipitation. Next, ionic strength effect of NaCl was employed to increase analytes distribution into organic solvent. A delipidation step then followed with hexane. Finally, decanted ACN layer was injected into the GC-MS system.

5 repetitions were carried out. The extraction procedure was verified by submitting a standard of geraniol to the complete protocol.

The verification of extraction revealed that 70% of geraniol was retrieved in decanted ACN. No aromatic compound was detected in all eggs from both tested groups. Indicating that the likelihood for EOs residues accumulation in eggs laid by hens regularly supplemented in feed with EOs for a duration of 10 months was poor. Further experiments are recommended to validate the efficiency and robustness of this method adaptation to determine aromatic compounds from EOs in eggs.

Publikationsverlauf

Artikel online veröffentlicht:
13. Dezember 2021

• References

• 1 Li X.. et al. « Development of precise GC-EI-MS method to determine the residual fipronil and its metabolites in chicken egg », Food Chem., vol. 281, p. 85–90, mai 2019, doi: 10.1016/j.foodchem.2018.12.041.