The yolks of avian eggs are an excellent source of nutrients for humans, Because they contain a their high level of proteins, vitamins, minerals, and polyunsaturated fatty acids (PUFAs). A variety of avian eggs are commercially available in different parts of the world. One common problem is that eggs are not always labeled correct, for example if chicken eggs are declared as free-range chicken eggs or relatively cheap quail eggs as more expensive pigeon eggs.

Meihu Ma, Huazhong Agricultural University, Wuhan, China, and colleagues used gas chromatography–mass spectrometry (GC–MS) to show that the fatty acid (FA) profiles differ significantly among the eggs of seven different species: duck, free-range chicken, silky chicken, quail, pigeon, goose, and chicken. Goose eggs have the highest content of saturated and mono-unsaturated FAs, but the lowest content of PUFAs, whereas the PUFA proportion was highest in chicken eggs. Also the volatile composition can be used to discriminate between all seven eggs. This finding was demonstrated by using GC–MS and an electronic nose (E-nose), a device that mimics the olfactory system by creating a digital signal after contact of volatile compounds with electronic sensors. Both methods show great agreement, thus making the E-nose a promising device for market quality controls of eggs.

• Discriminating eggs from different poultry species by fatty acids and volatiles profiling: Comparison of SPME-GC/MS, electronic nose, and principal component analysis method,
  Qingling Wang, Guofeng Jin, Yongguo Jin, Meihu Ma, Ning Wang, Chunyou Liu, Liyuan He,
  Eur. J. Lipid Sci. Technol. 2014.
  DOI: 10.1002/ejlt.2013400016