It's easy to see on a product pack its nutritional content, but can you know this when it's about meat? And especially the fat content?

Now, New Zealand food industry use a breakthrough x-ray based technology to ensure that beef exported to make American beefburgers obeys the US fat content regulations. These regulations stipulate that in the final product the fat content must not represent more than 22.5 %.

The IsoScan technology, made at the Institute of Geological and Nuclear Sciences (GNS), could turn into a widespread use to the point were food items like olive oil, fruit, milk and meat could all soon be x-rayed before reaching the supermarkets. The devices could eventually be employed by the consumers as hand-held scanners to investigate meat for tenderness when choosing it.

"The x-ray technology had scope to be used on a wide range of foods. A tenderness-measuring technology is in the works, and GNS is also investigating ways to scan fruit before it is packed for sugar content and color," said Rob Archibald, research and development manager at ANZCO, a company that processes and markets meat and which has been working with IsoScan since 2004.

"IsoScan use the same principles as machines that scann luggage in airports and did not affect food. It's non-invasive... Nothing breaks, you don't destroy the product." said GNS scientist Joe Manning.

"Although hand-scanners were a long way off, they were feasible, and so was the idea that most food would eventually be scanned before it was sold. IsoScan was used to check the density of timber and the fat content of meat, and meat tenderness was next on the to-do list," he added.

"The IsoScan machines could handle about 15 cartons of beef, weighing 27.2kg each, every minute and were accurate to 1%." said Archibald.