Field Reports
Upgraded metal detection recovers 5-10% more product from false rejects
The Thermo Fisher Scientific Sentinel Multiscan metal detector uses five frequencies to ensure product is free from foreign material.
Photo courtesy of Thermo Fisher
Cebro Frozen Foods, Newman, Calif., a bulk producer and supplier of organic, kosher and conventional individually quick frozen (IQF) vegetables to the industrial and food service industry, was founded in 1993 and is operated by third-generation grower and owner Patrick Cerutti.
About 95% of its primary crops, including broccoli, tomatoes and zucchini, are grown within a six-mile radius of the processing plant on the 6,000 plus acre farming operation.
Cebro handpicks its produce, and the team is trained to manually inspect products to catch any potential foreign material in the field and remove those materials before they make their way to the plant. Cerutti says that the manual inspection provides “an extra layer of due diligence” to the inspection process.
The fresh-picked produce arrives at the plant where it is immediately flash-frozen—a process where products are frozen very quickly at extremely cold temperatures to retain freshness and as many nutrients as possible. It is then that the product undergoes inspection with metal detectors before the bagging process begins.
Because metal detectors can deliver false positive results when products are wet, it’s important that the inspection process happens soon after freezing to avoid product effect issues resulting from thawing.
Need to Upgrade
Cerutti says he realized that Cebro needed to upgrade its metal detection technology to identify increasingly smaller metal foreign objects as a result of more stringent requirements from customers. He was also experiencing a problem with a new repack line where plant noise was interfering with the metal detectors, essentially “tripping” them and generating false rejects.
He reached out to Thermo Fisher Scientific to explore new metal detection options, and that is when he decided that the Sentinel Multiscan metal detector was the solution for Cebro’s needs. The Sentinel’s ability to inspect using five frequencies at a time provides the detection of metal foreign objects, including any potential issues with product effect.
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This is a common issue in a plant with many possible noise sources (e.g., large motors turning off and on, production equipment vibrating, etc.), which can disrupt the metal detector’s electronics and software.
The Sentinel is designed to change a particular frequency that may be susceptible to noise. It also addresses noise challenges with metal detector coils or antenna that are designed to cast in an extremely rigid material so they do not move in relation to the stainless steel case, which means there are no small, false signals created.
Additionally, the internal electronics are protected by multiple levels of shielding, ensuring fields from the outside do not get inside, affecting detection. The power supply rejects noise in the electrical supply, and a software filter is run on the detection signals to remove noise entering the aperture that is not at the frequencies of interest.
Since the Upgrade
Cerutti says the Sentinel’s multiscan technology and its ability to control the interference of noise during processing is enabling Cebro to optimize its inspection process, virtually eliminating false rejects and yielding a significantly higher percentage of saleable product. The company also is confident that its products are free from foreign objects, protecting consumers and the brand.
“We’re recovering an additional 5-10% of our products thanks to the Sentinel,” says Cerutti. “I’m loyal to Thermo Fisher Scientific and its guidance to help identify the right solution for our metal inspection needs.”
For more information, visit www.thermofisher.com
