Thermo Fisher Scientific Celebrates 65 Years Of Food Metal Detection

65 Years of Food Metal Detection
2012 marks the 65th anniversary of food metal detection. The basic principle of operation for the common food metal detector is based on a three-coil design. This design utilizes an AM (amplitude modulated) transmitting coil and two receiving coils, one on either side of the transmitter. The design and physical configuration of the receiving coils are instrumental in the ability to detect very small metal contaminates of 1mm or smaller. Today modern metal detectors continue to utilize this configuration for the detection of tramp metal.

The coil configuration is such that it creates an opening whereby the product (food, beverages, pharmaceuticals, etc.) passes through the coils. This opening or aperture allows the product to enter and exit through the three coil system producing an equal but mirrored signal on the two receiving coils. The resulting signals are summed together effectively nullifying each other.

When a metal contaminant is introduced into the product an unequal disturbance is created. This then creates a very small electronic signal that is amplified through special electronics. The amplification produced then signals a mechanical device mounted to the conveyor system to remove the contaminated product from the production line. This process is completely automated and allows manufacturing to operate uninterrupted.

It is difficult to think what damage could have been done to both consumers and food manufacturers if the metal detector had not been introduced to the food industry 65 years ago.

How Metal Detection Started
Toward the end of the 19th century, many scientists and engineers used their growing knowledge of electrical theory in an attempt to devise a machine which would pinpoint metal. The goal was to find ore-bearing rocks and this new invention could give a huge advantage to any miner who employed it. The German physicist Heinrich Wilhelm Dove invented the induction balance system, which was incorporated into metal detectors a hundred years later. Early machines were crude, used a lot of battery power, and worked only to a very limited degree. Physicist Alexander Graham Bell used such a device to attempt to locate a bullet lodged in the chest of American President James Garfield in 1881. The attempt was unsuccessful because the metal bed Garfield was lying on confused the detector.

The Metal Detector's First Patent
The modern development of the metal detector began in the 1930s. Gerhard Fisher had developed a system of radio direction-finding, which was to be used for accurate navigation. The system worked extremely well, but Fisher noticed that there were anomalies in areas where the terrain contained ore-bearing rocks. He reasoned that if a radio beam could be distorted by metal, then it should be possible to design a machine which would detect metal, using a search coil resonating at a radio frequency. In 1937, he applied for, and was granted, the first patent for a metal detector. His designs were soon put to the test in a practical way, as they were used as mine detectors during World War II. They were heavy, ran on vacuum tubes, and needed separate battery packs, but they worked. After the war, there were plenty of surplus mine detectors on the market; they were bought up by relic hunters who used them for fun and profit. This helped to form metal detecting into a hobby.

Goring Kerr Introduces Metal Detection For Food
One of the first metal detectors used for the food industry was pioneered by Goring Kerr in 1947 for Mars Inc. They used the Goring Kerr metal detector to inspect the Mars Bar. Goring Kerr was founded by Bruce Goring Kerr and David Hiscock (pictured on right). It was the first company to incorporate digital signal processing (DSP) technology in metal detectors, setting the standard for detection sensitivity.

Goring Kerr was spawn from a project for the British military. The founders decided that it would benefit the food industry to utilize a metal detection device to find hidden metal contaminants. This simple idea was inked in Goring Kerr's tag line "Seeing The Unseen." These metal detectors were truly capable of seeing what people couldn't and for the first time consumer safety was able to be realized in the modern food production environment. Food metal detectors such as the DSP 3 from Thermo Fisher all seek to find reliably the same thing, metal fragments.

Goring Kerr Becomes Part of Thermo Fisher Scientific
In 2008, Thermo Fisher Scientific (previously Thermo Electron and before that, Ramsey Engineering), celebrated the 60th anniversary of its flagship metal detector brand, Goring Kerr. Every model of the Thermo Scientific Metal Detectors provide the ideal QA means to implement your HACCP plans and incorporatesthe hygienic standards required in the food industry. Backed with 65 years of experience, the once Goring Kerr metal detector systems will assure your product to be contaminant-free, and protect your brand.

Goring Kerr Model History
1947: First food metal detector introduced by Goring Kerr for MARS in the UK

1961: First vacuum tube metal detector with launch of Goring Kerr 7M/7L vacuum tube metal detector

1963: Goring Kerr SJU – Mark II was the first transistor metal detector

1969: Goring Kerr SJU – Mark III introduced

1974: Goring Kerr Meltokate was the first modular system metal detector with five circuit boards: RF, LF, self check, timer and power supply boards.

1975: Goring Kerr SJPT is the first pharmaceutical metal detector

1978: Goring Kerr P1 is the first portable metal detector

1980: Goring Kerr Tekamet is first auto-phase metal detector for dry products

1988: Ramsey Metal Scout is the first fully potted head metal detector

1989: Goring Kerr Tek family introduced: Tek 21, Tek 21F and Tek 21C. The Tek21C was the first programmable metal detector.

1991: Goring Kerr DSP1 was the first metal detector to have Digital Signal Processing (DSP)

1992: Graseby purchased Goring Kerr

1996: Goring Kerr DSP2 introduced

1997: Goring Kerr DSP2S launched

1998: Audit-check added to Ramsey Metal Scout IIe was a patented feature that reduced need for production operators to manually test metal detectors

1999: Thermo Electron acquires Graseby Goring Kerr

2001: Goring Kerr DSP3 launched with Audit-check feature

2005: Thermo Scientific APEX 500 uses DSP technology and a unique multi-coil design to improve singal levels

2006: Thermo Electron becomes Thermo Fisher Scientific and APEX product line adds the APEX 100 and APEX 300

2007: APEX 300 Drop Through and APEX Pipeline metal detectors launched

2009: New integrations added to APEX product line. Thermo Scientific Intellitrack XR (IXR) is a unique patented product signal compensation feature for APEX metal detectors. APEX 500 Rx is the first pharmaceutical metal detector for the APEX family. The IP69K rating was given to the entire APEX metal detector family. This rating allows the metal detectors to be used for high pressure, high temperature wash-down applications.

2012: Thermo Fisher Scientific celebrates 65 years of innovation in metal detection

For more information on legacy Goring Kerr and new Thermo Scientific Apex metal detectors, visit www.thermoscientific.com/detect.