The European Union has backed DNA testing in the wake of the horsemeat scandal.
All 27 member states will carry out the tests on meat labelled as beef to look for traces of horse DNA.
The examination of some 2,000 samples will start immediately and last at least one month.
However, testing can be extended by an additional eight weeks if EU nations agree.
Scientists will also check horsemeat to check for residues of a harmful drug.
They will look for traces of the veterinary drug phenylbutazone, also known as ‘bute’, in some 4,000 samples.
Bute is an anti-inflammatory treatment, but is considered unfit for human consumption.
It is banned from entering the human food chain in the EU because it can cause cancer and other lethal effects.