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Experts in egg traceability

Egg consumption in the EU is around12kg per capita per year (Eurostat, 2011), and eggs are consumed in a variety of different ways, which is why we believe in ensuring the origin and organic status of eggs.

Animal welfare has become an important factor for customers on deciding which supplier or retailer to use. From free-range to organic, improving chicken welfare has become championed by many groups, such as the British Free-Range Egg Association (BFREPA) and OIE (World Organisation for Animal Health) in order to improve European farming welfare standards.

Higher welfare and ‘local’ eggs command a significant premium, but what really indicates an egg’s location is the egg code printed on each individual egg. For this reason, it is important to verify the origin of eggs using forensic methods, such as isotope analysis.

How does egg traceability work in the UK?

European eggs can be traced by the numbers printed on the shells. This number corresponds to a farm where the egg was laid, and how it was produced – such as 0 for organic, 1 for free-range, and 2 for barn eggs. There is also a system in place to help auditors track eggs back from pack to farm.


Here is a guide to how eggs go from gate to plate in the UK:

egg production UK
Egg production UK

As the above image highlights, it is also important to have a traceability system that includes analysis as well as digital traceability. Current traceability, based on mass-balance or paper records, is possible to trick in order to cheat the system, for example, by buying unlabelled barn eggs and labelling them as from an organic farm in order to make a profit.

Organic and conventional stable isotope testing in eggs

Organic eggs can be differentiated from conventional eggs because the chickens eat different food. In order for an egg to be organic it must have been laid by a chicken that has eaten a diet of organic food. Due to the difference in the origin of the nitrogen in the proteins in organic and conventional chicken feeds, organic eggs can be differentiated from conventional eggs by means of analysing their nitrogen stable isotope ratios.


Organic eggs show more enriched nitrogen ratios than conventional eggs (more positive than conventional) this is because they have relatively more 'heavy' nitrogen (15N) than conventional eggs.

Agroisolab offers isotope testing services to determine whether or not organic eggs are organic. Contact us for further details.

Is it possible to verify commercially produced eggs as 'free-range' using stable isotopes or trace element analysis?

Click below to download Agroisolab's paper:

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