Fast food image

Low-energy X-ray inspection technology said to produce fast, highly-detailed images of food products and packaged goods while still on the production line. Siobhan Wagner reports


An X-ray inspection technology using low-energy radiation can produce fast, highly-detailed images of food products and packaged goods while still on the production line, one of its European developers claims. The images are then scanned with inspection software that can automatically detect irregularities.

The technology, which is the result of the EU-funded Modulinspex project, was led by Innospexion of Denmark, with partners Zenon, Cavendish Instruments, Detectronic, AJAT and the University of Latvia.

Until now food producers have used high-energy X-ray technology similar to that used to scan luggage at airports. While these systems can find a tiny pebble in a package, they lack the resolution to image such things as a grain of sand in a bag of flour.

Low-energy X-ray technology is capable of imaging these irregularities but has not been used before on the production line because it requires longer exposure times, which slows the rapid pace of modern processing and packaging plants.

Jørgen Rheinlænder, managing director of Innospexion, said his group found a way to speed up the imaging by simplifying the process.

‘Other detectors first convert the X-ray image into a sort of TV image before feeding that information to an electronic device,’ he said. ‘We removed the optical link and directly attached a semiconductor to the crystal that detects the X-rays.’

The new detector, he said, is capable of taking 300 images/sec, sufficient to capture a crisp image of products moving on a conveyor belt at 0.5m/sec.

The images have a resolution of 0.1mm, which Rheinlænder claims is 16 times better than existing high-power systems. However, he said these systems are not designed to replace them.

‘Our system is aimed at a completely different market not yet covered by other technologies,’ he said. It can be used to check seals on food wrappers, locate packaging defects and find foreign particles of any size in any kind of food.

Rheinlænder said most people would probably be surprised by how common it is to find foreign bodies and packaging flaws in current food packages. ‘You can buy many products where you see the seal is contaminated,’ he said.

In some cases, he added, bacteria may spread on poorly-sealed produce and go unnoticed by consumers until they are taken ill.

While there are many important applications for the detector in food production, Rheinlænder said many of Innospexion’s customers are in other sectors. In the UK, the system is being used by one company to inspect filters delivered by an outside supplier. In Denmark it is being used to check the quality of fur used to make coats.

‘The market for this technology is enormous,’ he said. ‘In the food industry alone we can expect growth rates in excess of 20 per cent. we also see a market for using it in manufacturing — to inspect seals on car components, for example, or check for counterfeit products.’

The group has recently received interest from companies in the UK, Sweden and Norway which would like to use the technology to inspect food pouches.

Rheinlænder foresees demand for the technology in the food sector being driven not only by producers who want to offer better-quality products but also by increasingly stringent food safety regulations.

‘It’s a new product and a new market so it will take a little time before it picks up,’ he said.