The safest way to check products for foreign bodies is to inspect them when they are in sealed primary packaging. As a closing mechanism, metal clips pose a special challenge. Mesutronic’s X-ray inspection systems have been the solution for the Austrian company Rudolf Ölz Meisterbäcker GmbH & Co KG in Dornbirn.

This is how we bake today

Nestled against the Breitenberg mountain in Dornbirn, it is one of the most modern and sustainable bakeries in Europe. The family-run company’s new plant, which will be completed at the end of 2022, will produce high-quality baked goods. The sustainable business philosophy of Ölz der Meisterbäcker does not just involve optimised energy management, for example, by using photovoltaics or recovering baking heat. In the interests of animal welfare, the company also practises conscious use of raw materials. It was the first European baked goods brand to take the bold step of switching to certified free-range eggs, at around 25 million per year. To reduce additives and improve flavour, Ölz toast and sandwich breads are baked entirely without preservatives and packaged in a clean room after cooling. However, using metal clips for sealing pushes the conventional foreign body monitoring programme to its limits.

Ignoring metal and yet still detecting it

After the bag packer process, toast packages are fastened tightly with a clip. This step consists of two metal wires being connected by a carrier material, usually plastic. The shape of the clip, and its position relative to the package, are always subject to fluctuations that range from minor to major. This variability, along with the material used, makes it impossible to carry out a guideline-compliant inspection with a conventional metal detector. The detection accuracy to be achieved would be far above the acceptable standards.

Residual risks with early inspection

One way of avoiding this problem would be to inspect the bread before the primary packaging step. Inspecting the bread after it has cooled would provide reasonable detection accuracy. The inspection of baked goods with a metal detector is a valid option for minimising risk, especially for uncut products.

For sliced products, such as toast, this would mean a high residual risk because metal fragments could get into the product – for example, if the cutting tool breaks. If no secondary control stage is integrated, such fragments would end up reaching the end user without being recognised. The sealing system mentioned above can also introduce wire fragments into the outer packaging due to broken clips and machine malfunction. This specific issue of broken fasteners cannot be resolved satisfactorily even by using simple X-ray technology. The basic obscuration caused by the clips prevents parts of them from being recognised as foreign objects. That is why both options were out of the question for Ölz.

Safety with added value

For over twenty years now, the company of choice for all foreign body control requirements at Ölz der Meisterbäcker has been Mesutronic GmbH from Kirchberg im Wald in Bavaria. “The excellent collaboration, continuous further development, and the good price-performance ratio of their machines make Mesutronic the ideal partner for us,” said Walter Maurer, Production Manager at the Dornbirn-Wallenmahd plant. The easySCOPE X-ray inspection systems manufactured in Lower Bavaria fulfil all requirements for user-friendliness and detection accuracy. In addition, in collaboration with Ölz, the software function for clip masking and completeness inspection has been optimised in order to still be capable of detecting wire fragments reliably. Other contaminants are also detected – from metal or glass to dense plastics. These contaminants pose a risk even in the best production environments. There is also monitoring with respect to the presence and correct shape of the clips . Faulty products are removed from the product line safely and fully automatically using a special double air-jet reject.

These systems are integrated into the company’s own network structure, which is used to record production data during operation and to save all product images for seamless traceability. This ensures the highest possible level of safety for customers and consumers.

Partnership pays off

A trusting and long-standing collaboration makes it possible to continually take steps forward, provided that the parties involved are going in the same direction and share a drive to develop. “As companies, we are linked both by our long history of collaboration and by our shared values. A sense of responsibility is at the core of Ölz and Mesutronic – responsibility for our customers, our company and, first and foremost, for the work we do every day,” said Christian Boxleitner, the foreign body control specialist’s CEO. That is how both companies are constantly breaking new ground to improve the quality of their sustainable products.