Isotope testing for British pork

Why is isotope testing important?

SIRA acts as both a deterrent and an early warning system. We cannot test everything, but we can test enough to discourage bad actors.

Regular testing means we can quickly discover whether a product is or is not consistent with British origin and find out why.

The AHDB SIRA scheme, which has been running since 2009, aims to protect:

• Our ‘British’ brand
• AHDB 
• The BMPA’s Quality Pork Charter
• Producers and processors from bad actors
• The price premium of British pork
• Consumer confidence in British pork

The pork sector is on the front foot in driving the use of this technology, underpinning its reputation and protecting itself against food fraud.

How does SIRA work?

Fresh and cured pork products are purchased from retailers. A detailed record of each sample is kept, including where and when it was bought, its use by date, health mark and sample type.

The samples are then sent to a laboratory to be tested. Auditors also periodically collect samples directly from abattoirs and processing plants.

The levels of several isotopes within the samples are measured. The ratio of these isotopes is then compared to a reference database, which contains more than 1,400 samples of known origin.

The likelihood of a sample being British is based on how closely it matches the reference database.

A sample with less than 40% chance of being British is classed as a ‘warning’ and requires investigation.

Samples with 40–60% chance of being British are classed as ‘monitor’ samples, suppliers with repeat monitor samples are also investigated.

The test is accurate and correctly classifies over 90% of warning samples. It can also distinguish between British and Irish pork.

What if a sample has a low likelihood of being British?

If a sample is flagged as a warning, it is investigated by the British Meat Processors Association (BMPA). They conduct a full traceability investigation to find out why the sample is a warning.

It is important to remember that the testing cannot discriminate intent. A warning sample does not automatically mean fraud.

A sample might come back as a warning because:

• It came from an unsampled area, so there is no matching sample in the reference database; if this is the case, the area can be sampled and added to the database
• There has been a change in production method
• The sample is not from where it claims to be

If there is no satisfactory explanation of why a sample is flagged, there could be increased testing on that supplier or increased scrutiny or alertness of auditors during site visits.

How to get involved

The larger the reference database, the more robust the testing will be. If there are fewer unsampled areas in the database, we will see fewer samples being flagged because they come from an unsampled area.

We therefore urge all food business operators to get involved in collecting reference samples.

You can collect the samples yourself using a remote witnessing process operated by Food Forensics, the laboratory that conducts the testing.

Alternatively, auditors or Food Forensics staff can collect samples on your behalf.

If you have any further queries or want to get involved, contact Siobhan Slayven.

Further information