Demand for detection

A number of metal detection systems have just been installed at a major food processor in Holland. The eight Lock MET 30+ metal detectors now up-and-running at King Cuisine's facility in Udenhout will help the company meet stringent inspection criteria.

King Cuisine supplies salads, tapanades, sandwich fillings and ready meals in consumer and retail packs to supermarkets and food service establishments. Metal detection forms an integral part of a company-wide HACCP programme, which provides customers with assurances of strict quality control.

The diversity of King Cuisine's product portfolio means that a number of different inspection challenges have to be met, such as varying product signals, container sizes and different packaging materials.

Lock specified the MET 30+ metal detector with its proprietary ADC software - a versatile system, capable of achieving consistently high sensitivity in the face of these variables. ADC acts as a 'window to the detection envelope', taking signals from the metal detector and displaying them on-screen in graphical format.

The software's easy-to-interpret images allow the user to fine-tune the detector settings from a remote laptop to match the product being inspected - so the tiniest contaminants can be detected - whatever the product or packaging.

The high moisture content of such fresh products poses a further challenge as it can cause interference with the detector coil current. Equipped with an automatic product compensation facility, the MET 30+ records the profile of conductive products, then automatically tunes the detector to recognise the presence of metal contaminants, overcoming the problem of the signal given out by the product itself.

The metal detectors are positioned towards the end of each line, to detect any contamination while products are still in individual containers and before they are labelled and packed into crates, as this increases detection reliability.

"We've been working with Lock for some years now and have established a strong relationship, largely because as our business has grown, their pragmatic approach has provided us with flexible and reliable detection solutions," said Rien Braat, King Cuisine technical manager.

"If, as we hope, our turnover continues to grow, our requirement for metal detection will certainly rise too."

Lock Inspections Systems operates in a dynamic sector of the food equipment market, where innovations are continually being launched onto the market. The company recently unveiled the MET 30+ 3f, Waferthin and Vertical Fall metal detectors, which are designed to deal with inspection challenges faced by confectionery manufacturers.

Lock claims that the equipment is the first metal detector on the market to automatically operate at three frequencies - high, medium and low. The detector will automatically shift between frequencies as it recognises the profile of each product, allowing polywrapped and metallised film packaged product to be inspected on the same line using one detector.

Sitting above the vertical form-fill and seal-bagging machine, the MET 30+ Waferthin detector provides in-line inspection, policing the point at which the confection drops into the packaging. A multi-head weigher is used to weigh the product, which is then dropped into the bags by the bagging machine and sealed. In the event of contamination, sealing can be stopped and a double-length pack produced. A compact Waferthin, 25 per cent smaller than the standard model and measuring just 5 inches (12.5cm) top to bottom, is also available for installations where line space is tight.

The MET 30+ Vertical Fall detector is used to screen incoming ingredients - such as raw or processed carob and cocoa, sugar, peanuts and flour - at the start of the production line. Inspection at this stage affords significant cost savings as lower value ingredients rather than finished product and packaging are rejected.