Researchers have developed technology using millimeter waves that could allow food manufacturers to examine finished products through packaging and give advantages over x-ray detection, the current preferred method.
The Fraunhofer Institute's recently developed StandAlone MilliMeter wave Imager (SAMMI) uses wave sensors to see through all non-transparent materials.
The technology can test whether food products, have been properly filled and pick upon any impurities. It can also assess whether plastic seams on items have been packaged correctly and detect harmful contaminants.
The machine contains a transmitting and a receiving antenna on two opposing rotating plates. A conveyor belt transports an item between the antennae, while these send electromagnetic waves in a high frequency of 78 GHz. Different areas of the item absorb the signal to different degrees, leading any differences in composition to show up in images.
Fraunhofer's current device is no larger than a compact laser printer, but is not yet ready for industrial scale inspection. At present it can only see real time images and inspects small items no higher than 2cm. It also takes around two minutes to inspect a single item, but Fraunhofer are hoping develop faster machines for industrial use.
The development would take place in the next year and a half and a larger machine would be ready within a year that could can at up to six metres per second.
Fraunhofer has a small contract with Proctor and Gamble to detect contaminants in nappies, but despite exhibiting at a number of trade shows has had little interest from food manufacturers who are perhaps waiting for an industrial scale machine.
SAMMI machines would not be expensive for food companies as the parts used were readily available components from the automotive industry. For the small machine that has already been developed, costs are expected to be between €30,000 and €40,000. When an industrial machine has been developed, food companies could expect to pay around €50,000.
An x-ray machine would be almost three times more expensive on an industrial scale and companies must also take additional precautions that are not necessary with SAMMI machines.
Source: Fraunhofer Institute