Ishida’s AirScan inline system for detecting leaks in modified atmosphere packaging (MAP) has helped enhance quality control procedures for a new snack product from M-Back GmbH in Germany.
Being produced for dairy giant Meggle, the Ofenschnecke is a small puff pastry product filled with a combination of feta cheese and fresh herbs or spinach. The rolls are packed in thermoformed trays with fill weights of 180g and 300g. When the delicate pastries are packed, it is not uncommon for product traces to get into the sealing area of the trays. This can result in leaks, which may cause protective gas to escape and draw in moisture.
In rare cases, external factors can also cause holes in the film. If such defective packaging is not withheld from distribution, the shelf-life can be significantly reduced and the product appearance can suffer.
Head of the packaging department at M-Back Marcel Schwebler says: "We used to perform a visual inspection of smaller batches.
"However, this process was no longer practical, as output had increased significantly. So we looked for a fully automatic quality control solution that is 100% reliable."
Ishida AirScan uses laser technology to detect leaks of carbon dioxide (CO2), which is used in many MAP applications. The high-performance system checks each individual tray in less than 20 milliseconds for traces of escaping CO2. It can reliably find holes with a diameter as small as 0.25mm, at breath-taking speeds of up to 180 packs per minute.
Users will improve their product quality without any adverse impact on products, as the inspection process does not exert any pressure, unlike conventional inline seal testers, and is therefore completely non-destructive. The inline system can be integrated into existing packing lines in a few minutes, without requiring any modifications to existing conveyors.
The Ishida AirScan at M-Back has been placed at the end of the packing line, between other control systems and a labeller. Since its installation, quality assurance has reached new levels. About 3% of packs are identified as having a leak. These are eliminated using an air reject mechanism and transported to a collection chamber for subsequent repacking.
M-Back’s specification was to reliably identify leaks with a diameter of 0.4mm or above and compliance with this is regularly monitored by inserting a needle of the relevant size into packs and testing them.
Marcel Schwebler reports: "But we definitely find even smaller holes.
"By way of illustration, if you immerse the packs that have been found to be faulty in a water bath, you won’t see any gas coming out. In a laboratory, however, we can detect changes in the composition of the gas mixture."
In a two-shift mode, the Ishida AirScan checks 3,500 packs of Ofenschnecken per hour, which equates to a belt speed of 30m per minute.
Marcel Schwebler says: "There’s no alternative to the AirScan system when it comes to speed."
He also highlights the system’s user-friendliness and availability, pointing out that it is very easy and safe to operate and requires only minimum maintenance. No changes to settings are needed for product changeovers, only the height-adjustable control arm with the sensor head that needs to be adjusted to the different pack heights. Dry cleaning before and after each production batch is completed within ten minutes.
The production data collected can be printed out as shift reports. M-Back also wants to connect the Ishida AirScan system to production analysis software in future.
As well as the improvement in quality there is a significant reduction in labour costs, as the two employees who were previously required for visual inspection are now available for other tasks.
Marcel Schwebler’s verdict is correspondingly positive: "The Ishida AirScan inline leak detection system is worth its weight in gold to us!"
M-Back GmbH has its head office and production site in Gebesee near Erfurt. As a manufacturer of baked goods, the company produces a perfectly coordinated range of frozen and chilled products that can be heated before consumption, offering a high-level of convenience.
M-Back was established in 2009 and is majority-owned by the dairy products group Meggle, which is also one of the company’s main customers. With over 300 staff and state-of-the-art systems technology, the company produces several hundred million baguettes and bread rolls each year for delivery to wholesalers and retailers, as well as to food service outlets. M-Back does not operate under its own brand, but produces goods for its customers’ brands.