Alan Mutch, business manager for quality control equipment at Ishida Europe, explained: “Current inline systems typically apply pressure to the pack and measure the resistive force.”
But as he made clear, this could potentially damage product or the way it is arranged inside the pack. Where the gas pressure in the headspace was lower than normal, it could also trigger false rejects.
Where a ready meal or other product has been flushed with carbon dioxide, if any gas escapes from the pack, Ishida’s AirScan will detect its distinctive signature based on the reflected IR beam. Importantly, it is a non-invasive system. The current configuration cannot be used for any other MAP gases.
Mutch said the system could monitor lines running at up to 180 packs a minute and would detect leaks down to half a millimetre in size. “It can be positioned straight after pack sealing, or else just after other quality control equipment such as X-ray or checkweighing,” said Mutch.
As well as ready meals, Ishida listed poultry, some other cooked and uncooked meats, seafood and cheese as examples of products commonly using carbon dioxide as a protective atmosphere.
Mutch said the leak testing unit had been alpha and beta tested on manufacturing sites, but had not yet been installed at a customer. “We know of no-one else using this technology in this application,” he said.
Ishida said it had a long-term partnership with the technology company which originally developed the system, but which it declined to name. It stated that the technique had first been applied to other industries.
Honeywell Analytics has an IR-based gas monitor for refrigerants, including carbon dioxide, which is also called AirScan.
The PPMA show runs from Tuesday September 29 to Thursday October 1 2015 at the National Exhibition Centre, Birmingham.