Metal detection solution for Rea Valley Speciality Foods

Rea Valley Speciality Foods recently commisssioned what is arguably the most advanced metal detection solution yet to be installed by a UK food manufacturer.

Dedicated to producing meats of the very highest quality, Shrewsbury-based Rea Valley provides the finest grade tongue products for both the delicatessen counter and pre-pack market and maintains a product inspection routine that far exceeds any existing industry standard. As part of this inspection regime, the company is committed to providing a product as free from metallic contamination as possible and has previously purchased various metal detection solutions from another equipment manufacturer.

Wishing to invest in a solution capable of successfully detecting the presence of minute metal particles and slithers of metal in frozen meat products weighing up to 25 kg, and dissatisfied with the level of service and support provided by their existing supplier, Rea Valley asked Mettler Toledo Product Inspection to provide a solution that would not only offer the highest levels of metal detection, but would also accommodate such large product sizes.

Before creating a metal detection solution for Rea Valley, the Metler Toledo technical team first had to consider a number of key factors:

Firstly, in order to accommodate such large pack sizes, it was clear that a system with an extremely large aperture would be needed. Across the product inspection industry, it is widely accepted that the smaller the aperture, the greater the level of detection sensitivity. In its “R-Series Profile” range of metal detectors, the company offers unrivalled levels of sensitivity, performance, ease of use and reliability from machines with conveyor apertures of up to the size needed to inspect Rea Valley’s products.

Secondly, in order to provide the highest levels of metal detection (animal tongue in particular can pick up metal fragments as a result of grazing), and to compensate for the “orientation effect”, a state where a non-spherical particle of metal is easier to detect when passing in one orientation compared with another, it was decided that a solution containing three metal detectors – one straight and two angled at 40° would be required, as this would provide the very best opportunity of detecting as much metal contamination as possible, irrespective of its position (orientation), within each frozen block.

Prior to building the full-sized solution, Mettler first supplied a trial unit to Rea Valley for exhaustive testing procedures. Delighted with the levels of sensitivity and detection provided, Rea Valley then commissioned Mettler to build a full-size conveyorised product handling, detection and rejection solution based around the proven technology offered by their Profile system.

Integrating three R-Series Profile metal detectors onto a 6m conveyor line - and each with its scanning head positioned to provide unrivalled levels of combined detection capability and minimise any chance of the orientation effect occurring - the solution supplied to Rea Valley has now been in place for several months.

Rea Valley's Factory Manager, Mark Jones said: “We have been delighted with not only the three-headed metal detection system which has performed better than our expectations, but also by the way in which Mettler Toeldo Product Inspection looked at the application. They covered off all our areas of concern, and tested and researched the application before agreeing to accept the order, instead of simply saying “yes” - something that often happens when an order is being dangled in front of potential suppliers."

“Our solution has not only further improved metal detection levels for a customer who already works to the highest standards and views metal detection as an essential part of the production process, but has also enabled an increase in plant productivity by successfully accepting and testing larger pack sizes. In creating this new triple head solution, we have developed a new industry benchmark for those organisations requiring the ultimate levels of metal detection,” said Mike Bradley.