Isotopic fingerprinting may provide a unique way of combating fraud in international meat markets, where the New Zealand brand carries a premium.

Drs Doug Mackie and Russell Frew (Department of Chemistry) are exploring whether the unique isotopic signatures of fertilisers used in New Zealand are reflected in our meat.

Frew says current traceability systems are open to counterfeiting. "So we are looking at ways of utilising the inherent chemical properties of the product itself by looking at the natural trace elements and geochemistry that it derives from its environment."

There is a chance that other areas of the world may have a similar geochemistry, so Frew and Mackie want to utilise New Zealand's unique farming practices to see if they provide a unique signal.

"New Zealand soils are deficient in some areas and there has been huge investment in redressing that trace element imbalance," he says. "We want to see if farming practices have disturbed the natural geochemistry enough to provide that signal."

They are particularly focusing on isotopes as a way of distinguishing between substances that are chemically identical. For example, selenium will be different depending on whether it is derived from the soil, fertilisers or animal remedies.

Frew says they hope to detect, in the meat, the unique isotope ratio of the selenium that has been added through fertilisers or animal remedies.

"Once you have established that signature, it should be relatively simple to check whether a piece of meat is genuinely from New Zealand, or not."