Tech Update: X-ray & Optical Inspection
www.foodengineeringmag.com/articles/90662-new-types-of-foreign-material-and-product-flaws-detected

New types of foreign material and product flaws detected
X-ray, camera and laser sorting technologies are coming of age in new configurations and applications that improve productivity and reduce false rejects while detecting harder-to-find flaws.
May 13, 2013

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For food products, advanced hardware and software recognize visible imperfections such as discoloration or deformation; spot “hidden” faults based on a measurement of the content of water, oil or chlorophyll present; and “see” invisible flaws ranging from Aflatoxin on nuts to softness/bruising in blueberries to the presence of sugar ends and zebra chips in potatoes. Identifying transparent contaminants like glass and low-density materials including plastic is a new development.
For the packages containing finished product, optical inspection systems outperform traditional checkweighing systems that don’t venture beyond an analysis of the aggregate product weight. The newer technologies can examine a multi-ingredient product such as a ready meal and confirm that all components are present in the correct proportion and position.
X-ray systems are diversifying from single energy beam configurations to include several multiple beam styles in new configurations. These include the use of two energy beams that operate at different kilovolt levels at the same point of inspection and dual energy beams with similar energy levels operating in tandem, where the first beam diverts suspect product to the second beam for inspection. The product is rejected if there is a defect or contaminant. However, if the product is stuck together or on top of one another, it is diverted for reworking and then reintroduced to the inspection system for checking. An X-ray system can weigh a packaged product and detect metal, as well as inspect additional user-defined parameters simultaneously.
Industry drivers
Retailers are no longer just mandating metal detection or product weight; they are asking food processing companies to add an extra measure of inspection protection—such as X-ray, camera or laser systems—to remove contaminants and identify damaged or missing product. “We are writing codes of practice on product fill/underfill, conformity, missing product, the gamut,” says Laura Studwell, Loma Systems North American marketing manager. “Several firms have in-house standards that exceed their HACCP protocols, not only to protect themselves and ensure quality to their clients, but to differentiate their product from competitive items in the market and to meet future, more stringent regulations,” Studwell says.
Ray Spurgeon, product manager at Eriez, says he is seeing calls from major retailers mandating their suppliers put X-ray on their lines. “It started as a subtle admonishment, and now it is more of a corporate edict. We booked an order for 27 systems last year from one customer for that reason alone,” Spurgeon says.
Productivity is another driver. “Yield is a big motivator. We’ve developed a field potato sorter [FPS] that removes stones and other contaminants as the product comes from the field, to maximize the storage of good product,” says Bjorn Thumas, Tomra Sorting director of food market development.
“We also developed a new sorter and technology that can detect softness in fruit. [Shipments of products can be rejected if the percentage of soft fruit exceeds a set amount.] Our machine takes out the soft fruit, reducing the chance of a recall to near zero while enabling harvest of previously uneconomical fruit,” says Thumas.
Premium packaging is also challenging processors to stay ahead of the food quality curve. “Metal detection is ubiquitous as a first level of inspection, but if the processor has new detection requirements for even smaller bits of metal, they can have difficulties meeting those levels with a metal detector,” says Todd Grube, Heat and Control product manager, inspection systems. According to Grube, this can be more challenging if the product is not dry and neutral but wet or conductive, which decreases the sensitivity of the metal detector. “Examining a product contained within a metalized film brings another level of difficulty. These factors are convincing more processors to seek newer solutions,” states Grube.
Robert Rogers, Mettler-Toledo Safeline senior advisor of food safety & regulations, says each technology has value and should be examined carefully. “It all goes back to the customer’s original [HACCP or qualification] plans. It is not just about using any or every technology out there, but designing a good program around the correct selection of technology, making sure the process is documented, maintaining control over rejected product and understanding the risks with reworking a project or having an unsecured reject area. Users of an inspection system have to use effectively what the system is telling them,” Rogers says. “Metal detectors won’t detect stone or glass, and X-ray technology is still challenged to detect low-density metals like aluminum. The technology and system it is running under needs to run production successfully and also identify the smallest possible contamination, day after day,” says Rogers.
Dual energy X-ray inspection advances
Anritsu Industrial Solutions USA is expanding its X-ray product line with a new dual energy system that targets harder-to-find low-density contaminants. “Detecting minute pieces of glass or chicken bone, or even plastic, which is the holy grail of X-ray technology today, are some of the more difficult applications that challenge traditional single energy systems,” says Christopher Young, Anritsu Industrial Solutions business development manager.
Anritsu’s new dual energy system was introduced last year as a focused product targeting the poultry industry. The company offers nine different single energy models, including a new high-definition X-ray system for the inspection of lightweight dry products and products in small bags. The firm has more than 7,000 single energy units installed globally, but sees dual energy equipment as the next frontier.
“A single energy system might spot a low-density contaminant like a chicken bone in meat, but it may not see it all the time. You are always on the edge of detection if the contaminant does not have a lot of density. If you are looking for a defect that may be close in density to the product, or does not have a lot of signal, that could generate a high false reject rate if a traditional single energy system is set too tightly. Therefore, this type of application needs a different type of technology to find the imperfection yet keep false rejects low,” Young adds.
Anritsu’s dual energy X-ray system generates a low-energy and a high-energy image from a single X-ray generator. The system generates two separate images to enhance detection capabilities. “Items like a chicken bone react differently to different energy levels, so the image of the bone may show up better at 30 kV or at 60 kV,” Young says. Two points of data allow the system to determine concretely if the object is truly a contaminant.
Anritsu’s dual energy system works best on poultry products that are two to three in. and thinner. If the dual energy X-ray system is set up for a thicker product and realizes the dual energy isn’t adding additional benefits, it automatically switches to a traditional single energy system that looks only at the high-energy image.
All of Anritsu’s X-ray systems use very small high-definition diodes for image generation and offer a standard 0.4mm diode that can detect contaminants as small as 0.4mm diameter. The physical size of the diode is similar to pixels on a flat-screen television: the smaller the diode, the sharper the image. Anritsu also offers an Ultra HD diode that can detect glass and stones as small as 1.0 to 2.0mm in diameter.
Loma Systems created and installed three customized dual X-ray systems for the world’s largest manufacturer of chicken nuggets, where the second X-ray inspection operates as a second tier of examination, downstream from the first check.
Loma’s X4 single beam X-ray technology is at the heart of a complex line designed to meet a Six Sigma standard (four false rejects out of every one million inspections) while maintaining high productivity. “The most common form of false rejection is when two chicken nuggets become stuck together during the production process,” says Nicolas Prompt, commercial director at Loma Systems.
Loma designed the system so the first X4 unit analyzes the product for density, broken pieces, damage or malformations using the company’s 3-D modeling and image processing programs. If the first X-ray senses variation to set parameters, that product is directed to a second X-ray unit for additional inspection.
“The second unit provides a second opinion, where the operator can look more closely at the product and determine why it triggered a reject response from the first X-ray,” says Studwell. If the product is stuck together, it is redirected after the second X-ray to a special recirculation/reworking path, sent through the system again and diverted to the proper accept/reject conveyor.
Eagle Product Inspection offers two related dual energy technologies, according to Simon King, global head of sales, service and marketing. Material discrimination X-ray (MDX) targets general food processing applications. Eagle’s DEXA dual X-ray technology, designed specifically for fat and lean analysis determination in meat, uses two separately generated high-energy spectrums to evaluate material content. “The technologies look at the degree of energy absorption by the material. Different materials have varying absorption rates depending on their density; the higher the atomic number and density, the more X-ray energy is absorbed. We are able to look up on the atomic table what the reference of a material is and determine the composition of the material,” says King.
Both X-ray approaches rely on Eagle’s SimulTask software to process the data. The software allows users to set parameters and tolerances, and spot defects down to 1.2 to 1.5mm, a range where many manufacturers increasingly set their tolerances, says King. Eagle has extended the capabilities of the software to provide more detailed analyses of product throughput and quality-related issues. Line operators can tie the analysis to traceability software to achieve a more seamless view of product management flow. The new TraceViewer enhanced analysis package is scheduled to be made commercial in the Spring of 2013, says King. The software can be programmed to identify every product coming through, including products having several different ingredients with differing requirements, such as panettone bread or a ready meal.
The company will introduce a new Multi-Bulk product that will allow users to run multiple lines of product to and through a common X-ray inspection control point, or handle higher volumes of product. DEXA can measure all the densities and contrasts in the product, allowing for much higher contaminant detection. Pack 400 HC, a new sanitary unit for use with Multi-Bulk applications, is designed to eliminate potential food collection points while providing ease of disassembly and washdown.
Single X-ray beams
X-ray units have the ability to perform density-based inspection to check the weight of a product and more. Loma Systems says the X-Weigh software and the Box Erosion algorithm for its X4 technology solved a problem a well-known confectioner was experiencing with fruit snacks sold in packets of six to a box. The confectioner used checkweighing and hit its target weight accurately and repeatedly. However, customers were complaining that only five packets turned up in the box. Now Loma’s Box Erosion feature allows the X-ray to see through the box and past the metalized foil film of the packet, while the X-Weigh system confirms the product meets weight requirements, says Studwell.
Loma also wrote a special algorithm that helps a cheese wheel producer in Wisconsin inspect the wheel for holes without slicing it open. The number of holes and the size of the holes in the cheese determine its quality. The moment the wheel is cut, its value drops significantly. “X-ray will not reveal the age of the cheese, but it can provide the data to determine its quality,” says Studwell.
Heat and Control has rolled out an economical line of single beam X-ray units. The IX-EA series complements the fully featured IX-GA series the company offers from its Ishida Co. division. The unit is configured as an entry-level unit that handles a limited range of products compared to the company’s higher-end models, says Grube. “It won’t find the smallest contamination, but it can help processors meet several requirements they were not able to achieve with metal detection or checkweigh.”
Eriez added to its product line a new X-ray inspection unit that detects foreign objects, product fill level and item presence in upright, non-glass containers. Its new E-Z Tec XR-SS unit provides side shoot scanning of missing or broken product and conducts mass inspection of metal, glass, stone, bone and some plastic contaminants. Product count, seal integrity, weight, shape, item position and presence/absence of product also can be detected. Other features include tool-less disassembly for cleaning ease, a low-profile design with compact 60-in. overall length and an auto-learn feature to quickly set operating parameters. The model joins the Eriez E-Z Tec X-ray line for packaging, meat, poultry and sanitary applications, and bulk flow materials.
Eriez has also developed a novel masterbatch additive for plastic products that make them metal- or X-ray-detectable. “Many major restaurant chains are mandating that food manufacturers use metal- and X-ray-detectable plastic and rubber articles as part of their HACCP programs,” says Eriez’s Spurgeon.
The additive is designed to detect and reject unwanted plastics that get into the food stream, including parts of scrapper tools, cable ties, pens, pallets, scoops, O-rings and belting. Eriez offers the PolyMag Beige XRD for X-ray detectable applications that require a high level of X-ray contrast and PolyMag Gray HSCP and PolyMag Black HSCP for metal detection and darker color pigmentation and black applications, respectively. The PolyMag additives applications are regulated by FDA for use in single- and repeat-use food contact plastic and rubber. Plastic molders typically include the additive at a 10 to 20 percent loading. Eriez says test cubes made with a 10 percent PolyMag loading were similar in detection to a 1mm mild steel sphere.
Mettler-Toledo Safeline launched a new energy-efficient single-beam model targeting small and medium-sized packaging inspection. The new X3310 X-ray inspection system employs a lower wattage generator that does not require cooling, reducing its power consumption by 20 percent, according to Rogers. The unit is offered with beam widths of 300 or 400mm. Although the system uses less energy, it can still detect an array of contaminants. “The imperfection does not have to be more dense than the product per se; it just needs to stand out within the image enough for the software to key in on it to understand it is a variation,” says Rogers.
Hyperspectral highlighted
Laser sorting can be used in applications to spot defects similar in color, structure, size and shape to the product. UV, IR and NIR ignore the color and look at how the product interacts with light, whether the light is absorbed, diffused or reflected. The basic premise behind the technology has been unchanged for decades, but its capability has evolved.
Hyperspectral technology is one of the more intriguing developments in inspection technology today. It examines the product by evaluating it through the electromagnetic spectrum, collecting hundreds of data points from multiple wavelengths in the NIR spectrum. The imaging systems divide light into hundreds of narrow bands over a continuous range that covers a vast portion of the electromagnetic spectrum. The data points are combined, creating a profile, signature or fingerprint unique to each product. The hardware and software program has to be capable of processing the hundreds of data points. Similarly, multispectral technology scans the same wide range of the spectrum, but it does not look at every single piece of the wavelength. It generates a less complex fingerprint.
Key Technology says a new era of digital sorting is arriving with the development of hyperspectral systems with new sensor technology and greater software-driven intelligence. “Key Technology continually develops more capable software and algorithms that enable the sorter to make new kinds of intelligent decisions,” says John Kadinger, market manager at Key Technology.
Key has developed “smart sorting” solutions that combine hyperspectral imaging technology with proprietary algorithms included in its software. Its BioPrint hyperspectral technology targets processors of potatoes, nuts and dried fruits. “With hyperspectral imaging, the sorter is not looking at the contrast between good and bad. It looks at a multitude of data points that define the overall product to tell you what is good. Any inspected item that does not exactly match the parameters for that product is considered bad,” says Kadinger.
Sugar ends and zebra chips are quality control issues in potatoes that cannot be detected reliably with traditional trichromatic cameras or lasers. Products processed from sugar end potatoes exhibit undesirable dark brown areas that only become visible after the product is fried. They are caused by a higher concentration of reducing sugars caramelizing. “Other technologies like UV cannot detect the reducing sugar because there is not enough contrast between the sugar and the flesh of the potato. Our BioPrint technology shows tremendous potential in detecting sugar end potatoes and other invisible defects,” says Kadinger.
One new example of higher sorting intelligence is Key Technology’s Sort-to-Grade function for French fries. The Sort-To-Grade function, part of the company’s KeyWare control for potatoes, considers the size and color of each defect and how passing that particular defect will impact overall final product quality, in comparison to product specifications. It evaluates major and minor imperfections, always removing major flaws.
“However, if the sorter encounters a minor flaw that is surrounded by good product, the technology decides whether to let it pass or reject it. It may not eject the minor flaw at the risk of also ejecting good product,” says Kadinger. Sort-to-Grade notifies the operator to take corrective action when it is not possible to maintain final product quality due to the quality of the incoming product.
Key says technology and software enhancements like these move processors away from the traditional sieve approach, where operators subjectively adjust accept/reject thresholds to make grade while staying within acceptable limits of minor and moderate defects. “The sieve approach results in too many defects being expelled, along with inadvertent ejection of good product, translating to a significant loss in yield,” says Marco Azzaretti, Key Technology advanced inspection systems product manager.
Visys NV, a supplier of sorting equipment now merged with Key Technology, applied its hyperspectral technology in a reverse sorting application featuring a high incoming defect load. It removed 98 percent of the walnut flesh left in a waste stream of walnut shells and membranes. Last year, Key Technology introduced a new three-way sorter that divides the product into good produce, foreign material/rejects and a co-product or rework stream. The system, now an option for its Optyx and Manta sorters, lets the processor recover product that is not in grade with the premium product but useful in another application. For example, walnut processors use three-way sorting to sort out pieces from unbroken halves that command a premium price, while also removing shells and foreign material.
Best NV, an optical sorting technology supplier acquired by Tomra last year, launched its Slidex sorter, which relies on NIR hyperspectral imaging to detect foreign materials such as plastic or wood. Features of the unit include a 1,000mm inspection zone, detection capacities up to 4 tons/hr. with efficiencies as high as 98 percent, depending on the incoming product.
Tomra has delivered a new sorter it says can for the first time recover almonds from the reject stream at the cracker process. The solution uses hyperspectral technology Tomra commercialized less than two years ago. Almond hull and shell pieces create a lot of debris, but 1-3 percent of the almonds are discarded with them. “There was no optical or mechanical solution to recover the almonds from the reject stream of shells in an efficient way until now,” says Thumas. Tomra has also delivered sorting technology that can detect worms in native pecans. “The hyperspectral scan is so specific that it creates a unique fingerprint of the almond. It pulls the nut from the reject stream in a reverse sort,” says Thumas.
A new field potato sorter (FPS) launched in December by Odenberg and Best—part of Tomra Sorting Solutions—utilizes multi-spectral NIR technology to remove soil clods, stones, rotten potatoes and foreign materials at rates up to 80,000kg/hr. It is the first offering by the company into the unwashed potato market and replaces difficult-to-recruit human labor for this task.
Catching chlorophyll
Sorting product based on the presence or absence of chlorophyll is a new and novel approach to sorting contaminants from peas, green beans, spinach and leaves on fruits. A patented laser fluorescence technology developed by Best— through research with the University of Brussels—creates high contrast to detect color and texture differences.
Best’s Fluo laser technology can determine the level of chlorophyll in a product and can spot objects or parts of objects—such as rotten spots or leaves situated in between product—that also contain chlorophyll. Fluo results in high detection and low false rejects, says Thumas.
Key also offers a fluorescence-based laser technology that determines the presence or absence of chlorophyll. “The presence of chlorophyll in corn may indicate the husk or shank is there, so you can find it and remove it. The technology can distinguish between the pea pod, which has chlorophyll, and the pea, which does not, and reject the waste,” says Kadinger.
Detoxing nuts
The detection and removal of Aflatoxin in nuts and dried fruit is area of development in optical inspection. Aflatoxin, said to be one of the most toxic substances known to man, is invisible, making it tougher to validate its removal from the product. Tomra’s Detox sorter subjects the fungus to a particular wavelength of energy and then captures the extremely low intensity of light reflected by the toxin. “It reflects light with a distinctive pattern or biological fingerprint. The laser system recognizes the biological signature of the Aflatoxin, even though it is invisible to the human eye, and can remove the contamination from the product at high flow rates,” says Thumas.
SWIR for frozen fruits
Detecting contaminants in frozen fruit and vegetables based on water content is the targeted application for a unique laser-based technology that employs shortwave infrared. The SWIR technology, offered by Tomra, identifies the large contrast between good product and contaminants based on how the wavelength of the shortwave energy is treated. Water-based products such as frozen fruit absorb the light, whereas defects such as wood and plastic reflect it. Contaminants of glass, cardboard or metal can be detected and rejected by combining several wavelengths with SWIR.
Camera system in review
Mettler-Toledo CI-Vision says its camera-based technologies continue to add new techniques for label identification, label location and imaging styles. The company has developed a new method for 360-D inspection that can make accurate measurements of label position using four cameras set at 60° angles to get images of the complete container surface.
Mettler’s software stitches the images of the bottle together into a full image and then flattens it, creating a 2-D panoramic view of the inspection surface. “In the past systems, you could not accurately tell label position because the bottle may have shifted while it was on the conveyor,” says Aaron Poppleton, Mettler CI-Vision technical writer. Using the stitching algorithm, the resulting image can be measured to ensure labels—even multiple labels—are positioned correctly on the surface of the container.
Mettler-Toledo CI-Vision also offers a paneling or “mosaic” technology for 360° inspection, which employs six cameras and is designed to capture every angle of the bottle to obtain a complete image of the label. Regardless of how the bottle comes into the system, Poppleton says the machine can show operators if the label is printed correctly, is valid and is free of any rips or other defects.
Poppleton says new camera lens options also allow for the examination of unfilled bottles with smaller neck openings. Higher-resolution lenses help to produce a sharper image of containers with less distortion. The company is also developing technology that allows for inspection of a tight seal on rigid products with a foil top.
New detection solution designed to meet growing food safety standards
Thermo Fisher Scientific introduced the NextGuard X-ray detection system designed as an affordable unit with features often found in more costly higher-end systems. The new unit helps expand the technology to a wider customer base.
The first model, the NextGuard C330, is designed for packaged product contaminant detection and complements the mid- and high-end Thermo Scientific Xpert and POWERx X-ray inspection systems.
“Based on customer feedback, we’ve found that, traditionally, the total cost of ownership for X-ray systems has been too high for many companies to justify this technology,” says Bob Ries, lead product manager, metal detection and X-ray inspection, Thermo Fisher.
Based on Thermo Fisher testing, NextGuard offers up to 50 percent better detection sensitivity than Thermo Fisher’s previous value-based X-ray system, the EZx.
Features of the NextGuard system include its compact one-meter long size; multiple contaminant detection algorithms to increase detection probability; ability to modify, test and change detection parameters on the fly; wraparound detector intended to reduce ‘blind spots’; on-machine reject image storage for up to 90 days, and a QA check mode that automates operator audits and recordkeeping.
NextGuard’s features have also been driven by a changing industry landscape “where X-ray detection addresses a number of customer concerns, including evolving HACCP standards and requirements from some retailers for X-ray inspected product,” says Ries.
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For more information:
Todd Grube, Heat and Control, 717-519-5240, toddg@heatandcontrol.com
John Kadinger, Key Technology, 509-394-3577, jkadinger@key.net
Christy Miller, Eagle Product Inspection, 813-342-2373, christy.miller@eaglepi.com
Aaron Poppleton, Mettler-Toledo CI-Vision, 630-446-7700, aaron.poppleton@mt.com
Ray Spurgeon, Eriez, 814-835-6298, rspurgeon@eriez.com
Laura Studwell, Loma Systems, 630-681-2055, laura.studwell@loma.com
Bjorn Weyts, Tomra Sorting NV, 32 16 741 906, bjorn.weyts@bestsorting.com
Christopher Young, Anritsu Industrial Solutions, 847-419-9729 ext. 306, cyoung@us.anritsu-industry.com
Robert Rogers, Mettler-Toledo Safeline, 813-342-9138, robert.rogers@mt.com
Bob Ries, Thermo Fisher Scientific, 763-783-2794, bob.ries@thermofisher.com
Mergers and Acquisitions in Inspection Systems
Key Technology Inc., a Walla Walla, Wash.- based provider of belt-fed optical camera/laser sorters, vibratory-, motion- and electromagnetic-conveyors and processing equipment, entered into a merger agreement in February with Visys NV, Hasselt, Belgium, a supplier of chute-fed in-air sorters and advanced laser detection technology.
Vysis will operate as a wholly-owned subsidiary of Key Technology and in the long-term equipment from one company will also be produced in the factory of the other. Frank Zwerts, formerly president of Vysis, is named president of Europe, Middle East, India and Africa for Key Technology. Zwerts will maintain an office at Key’s technology center in Beusichem, the Netherlands.
Vysis offers a fully digital laser sorter, where the light from the laser contacts the sensor and is immediately digitized. Key offers a digital sorter, however its approach processes the reflected laser light through an additional sensor technology before digitizing the image.
Vysis also pioneered work in the development of BioPrint Hyperspectral imaging technology, which uses a broad range of wavelengths within the NIR spectrum to create a unique fingerprint of the product. Key has targeted the potato processor as a primary strategic market with its technology, while Vysis chute-fed systems and technologies focus primarily on nut and dried fruit applications. Both technologies are used to treat wide array of vegetables and fruits.
Tomra Sorting Solutions, Asker, Norway, late last year acquired 100% of the shares of Belgian Electronic Sorting Technology (Best), Kwadraat NV, Belgium, a supplier of laser- and X-ray based free-fall sorting technology. The acquisition brings several advanced optical sorting inspection technologies under a single roof while complementing Tomra’s existing belt-sort solutions based on laser, camera, and X-ray technologies.
The acquisition is the second purchase of a food-focused supplier of optical sorting equipment and technology by the Tomra Sorting Group. In 2011 it purchased Odenberg Inc., a West Sacramento, Calif. - based supplier of optical sorters, graders and peelers. (Odenberg also manufacturers a fat analyzer for the meat industry). Tomra recently sold the chilling/freezing unit from Odenberg to a newly formed company, Power Food Technology Ltd., of Ireland.
Tomra offers its technologies for the food industry under the Tomra Best and Tomra Odenberg brand names. “Best and Tomra Sorting complement each other perfectly in terms of technology and market coverage,” says Best CEO Paul Berghmans.
Mettler Toledo Group, a global manufacturer of precision instruments for use in laboratory, industrial and food retailing applications, in March 2011 acquired Eagle Precision Inspection, which supplies two dual X-ray technologies and a Quad beam approach.
Eagle, formerly known as Smiths Detection Product Inspection, will continue to operate as a separate business entity, and will compete in the marketplace against technology from Mettler Toledo Safeline, suppliers of X-ray technology, and Mettler CI-Vision, which offers camera-based vision systems. Eagle opened a new R&D facility new Wiesbaden, Germany, invested in a new engineering lab and testing/demonstration center at its headquarters in Tampa, Fla., and is establishing a new team of product specialists in Shanghai. Nick Marck was appointed to the post of North American business manager.
Robert Rogers, Senior Advisor Food Safety & Regulations, Mettler-Toledo Safeline
FE: What are the primary drivers behind demand for X-Ray systems? Is it to enhance a company’s Continuous Improvement Program or to better adhere to Good Manufacturing Principles; are retailers mandating its use; to meet compliance with existing or upcoming regulations?
Rogers: Foreign material prevention programs are the key drivers for X-ray inspection systems. Most retailer standards, GFSI recognized programs and food safety laws and regulations require a foreign material prevention program. As most programs contain basic HACCP requirements, physical contamination is a potential hazard that must be considered.
FE: X-Ray can detect metal contaminants or identify missing product in a package. What more can it do, and what do these capabilities mean for food safety and food quality?
Rogers: X-ray inspection systems are becoming more commonplace in the industry. Capabilities to detect not only metal contamination but also other dense foreign material such as glass, stone and bone have increased its use within food safety management programs. X-ray systems can inspect other aspects of the product such as size, count and even verify proper items have made it into the pack. Another use for X-ray inspection systems is product amount such as fill level detection and overall and zone mass capability as a way to verify proper product amount.
FE: Is glass detection the sole application warranting the selection of a multiple beam system over a single beam system?
Rogers: With a single beam system, you have only a single view of the product. There are potentially areas in the product that are hidden from view and could potentially mask contamination making it undetectable. This is often the case when inspecting glass jars, bottles, and canned products, the use of multiple beam systems provides an increased coverage of the product ensuring all areas of the product are visible to the system as well as allowing each area to have independent sensitivity settings increasing detection capability.
FE: What market segments have you been able to penetrate with this technology?
Rogers: X-ray systems are utilized throughout several industries including the food, pharmaceutical, beverage, snack, pet food and packaging material industries.
FE: What is the smallest contaminant detectable with your X-Ray unit?
Rogers: Typically, the limiting factor is the product being inspected. The question is not what is the smallest the X-ray system can detect, but rather what is the smallest contamination the product will allow the system to detect. The best way to set up any inspection device is to successfully inspect production limiting or better yet eliminating false rejects. Ensuring good product is able to pass through the system successfully allows better control of the overall process. Ideally, each rejected product is investigated leading to the source of the contamination allowing corrective action to help prevent reoccurrence. With frequent false rejects the potential losses can add up fast such as product waste, production loss and reworking costs and the fact is it should never have reject in the first place.
FE: Is operating, adjusting and maintaining this equipment easier now than say five years ago? If so, how?
Rogers: Improvements in the user interface and data collection capabilities have certainly improved the ease of use. Older systems might have required a engineer to set up and adjust the system, today’s systems have features such as automatic product set up, automatic performance verification capabilities as well as image capture and other data reporting capabilities making the systems not only easier to use but also allowing easier integration into a robust food safety programs.
FE: Can X-Ray detection be used to track the source of a contaminant or missing product?
Rogers: Detection of contamination is actually the easy part, the identification of the source and preventing reoccurrence is the challenge. True benefits are realized when an organization incorporates inspection systems as a part of a complete food safety and quality program. Locating the source of the contamination and implementing corrective action and revention measures is not only a good practice it is often a requirement in food safety management programs and regulatory requirements.
FE: Are users of your X-Ray equipment including this technology in their HACCP standards?
Rogers: HACCP and HARPC type programs are the leading reasons to incorporate a foreign material inspection device. Not only installing a device but developing a robust foreign material prevention program incorporating its use will help facilities and organizations reduce the risk of detrimental recalls and help to protect the brand image.
FE: Are users of X-Ray technology replacing metal detectors or camera-based optical systems as the primary means of product or package inspection, or combining them? If in combination with other inspection equipment, tell me how they work together.
Rogers: Unfortunately, there is no “Silver Bullet” for inspection devices. There are advantages and disadvantages with both metal detectors and X-ray systems. Metal detectors are unable to detect non-metallic type contamination and aluminum contamination is a challenge for X-rays. A complete and thorough hazard analysis may highlight the need for both technologies to be utilized. Both are also application dependant, some applications are best suited for metal detection and some are best suited for X-rays.
FE: Overall, would you characterize market use of X-Ray as still a nascent technology, one experiencing steady growth, or already at fully maturity?
Rogers: Experiencing steady growth and an increased acceptance for foreign material prevention programs.
FE: What would you say is the biggest impediment to X-Ray adoption today?
Rogers: Cost has been a leading impediment in the past however there are several systems available at several different price points so this is becoming less of a factor.
Laura Studwell, North American Market Manager, Loma Systems
FE: What are the primary drivers behind demand for X-Ray systems? Is it to enhance a company’s Continuous Improvement Program or to better adhere to Good Manufacturing Principles; are retailers mandating its use; to meet compliance with existing or upcoming regulations?
Studwell: Many governing institutions worldwide are requiring food processing companies to implement a documented food safety management program based on HACCP standards and now, the Food Safety Modernization Act. Leading retailers are also becoming more stringent with their codes of practice, requiring food processing companies to add an extra measure of protection against contaminants as well as identify damaged or missing product.
Many retailers and food processors are concerned with protecting their brand identity, which is the major driver behind the demand for x-ray inspection systems. Retailers do not want to represent products that could potentially generate liability. Liability can mean harm to the consumer through contaminated or damaged products or it could mean lack of satisfaction due to missing product or under-filled product. Likewise, food processors vying to put their products on retailer shelves, at an often low negotiated cost of placement, want to ensure they are not giving away product by over-filling. Integrating an x-ray inspection system inline either at the beginning or at the end of the line can negate all of the above potential issues.
FE: X-Ray can detect metal contaminants or identify missing product in a package. What more can it do, and what do these capabilities mean for food safety and food quality?
Studwell: X-ray inspection is the most comprehensive detection technology available on the market. Unlike traditional metal detection systems, the x-ray can detect metal contaminants even for products packaged in foil or metalized film. It can also detect non-metallic contaminants such as glass, stone, calcified bone, high-density plastics, flavor clumps and rubber. In addition, x-ray inspection systems can simultaneously perform a wide-range of quality checks such as measuring density, monitoring fill levels, identifying missing or broken products, counting components and checking for damaged or malformed packaging.
One of the features the X4 x-ray series brings to the market is Loma’s unique algorithm that detects, counts and measures the holes in cheese wheels without actually cutting the product. This feature is significant to the industry because the diameter of the holes determines the age of the cheese. The ability to keep the cheese wheel intact allows the processor to sell the wheel at a higher price on the market.
Food safety and food quality go hand in hand in the inspection industry. Many things can occur that affect the quality of raw material such as location of import and choice of transportation of raw material due to fuel prices. Many factors in the economy will cause changes to where and how raw material is obtained. This directly affects the beginning stages of processing, but with the x-ray being the most comprehensive inspection system on the market, it negates these concerns and allows processors to meet or exceed regulatory requirements and codes of practice.
The x-ray can measure the density of products, even determining if an onion is rotten under the peel.
FE: How many X-Ray units have you installed in the U.S.? How would you characterize U.S. market acceptance of your X-Ray technology?
Studwell: We have over 1,000 x-ray inspection systems installed in the U.S. but our reach extends globally.
Today, metal detection remains as the most familiar form of food inspection. It has roots that go back as far as World War II. Over the past decade, x-ray inspection technology has grown at a steady rate. In the past 3 years, however, the technology has become more recognized and accepted by the U.S. market. Many of the major retailers are specifically requiring x-ray inspection as a second line of defense in their codes of practice. This protects potential lawsuits from consumers regarding non-conforming products.
Product recalls cost the food industry over $7B annually according to the Washington Times. To avoid costly issues, many food processors are proactively integrating x-ray inspection systems in line at either at the beginning or at the end of the line.
We recently performed a case study with long-time customer, St. Clair Foods, based in Tennessee. St. Clair Foods distributes their signature products to restaurants nationwide and also markets their products on QVC, national television. St. Clair Foods proactively implemented an X4 PipeLine system at the beginning of their line to improve the quality of raw materials before entering the processing stage. Since then, they have been able to share inspection results with their suppliers and help them improve their processes as well.
FE: Is glass detection the sole application warranting the selection of a multiple beam system over a single beam system?
Studwell: Detecting glass in an application, such as bulk flow products (cereal, grains, etc.) only requires a single beam system.
However, if you are looking to detect a glass contaminant in a glass bottle, you would need a ‘dual beam’ system.
The X4 series has a unique feature that erodes the edges of packaging via image processing. Eliminating the edges of the packaging allows the user to view only the product and therefore achieve better sensitivity.
FE: What market segments have you been able to penetrate with this technology?
Studwell: From food and beverage to pharmaceutical and even academia and education, x-ray inspection is used across a broad spectrum of market segments. We have had success in the meat and poultry industry, where many processors use the x-ray technology to identify bone fragments.
FE: What functions or features distinguish your X-Ray technology from competing models?
Studwell: Loma has made significant advances in x-ray technology over the past decade. The X4 series boasts the highest sensitivity rates at three times other industry systems. The X4 series utilizes proprietary 3D image processing and modeling software to display clear product images so the operator knows exactly where a contaminant is located within the product.
X-ray tubes are extremely costly and depending on usage rates, need to be replaced frequently. Loma has developed a unique technology that extends tube life at 7 to 10 years. This is more than triple the life of other tubes on the market.
Loma developed a unique algorithm that detects, counts and measures the holes in cheese wheels without actually cutting the product. The algorithm also provides for the package erosion feature, where package edges are eroded so the system only inspects the product on the inside.
Loma’s patented Explorer feature identifies and documents areas of different shades. A cathode ray creates a fan-shaped x-ray beam that scans the product. Grayscale data is collected at scan rates relative to the amount of x-ray energy received. The data is digitized by the software and identifies an area that has a different shade. It has the capability to then focus on that area for further inspection.
X-weigh combines x-ray functionality and check weighing functionality into one system. Check weight and contaminant detection simultaneously using an algorithm based on the density of the application versus the industry standard load cell technology for weighing. X-weigh is unaffected by pack rate, speed, vibration, air turbulence, pack orientation or stability and requires little maintenance unlike a traditional check weighing system. The X-weigh software complies with national weights and measures legislation and automatically calculates the correct reject set points for American Minimum or MAV weight control. A great example is yogurt, as X-weigh can check for contaminants through the foil seal as well as monitor fill level.
FE: What is the smallest contaminant detectable with your X-Ray unit?
Studwell: 0.6mm is the smallest contaminant detectable with the X4 x-ray series.
FE: How well does your system detect low density contaminants?
Studwell: Low density products are hard to detect for the x-ray technology. Many of the low density contaminants processors are looking to identify are plastics. Plastic can be detected depending on its density. The level of detection capability depends on the application itself and product testing is usually required to provide an accurate measurement of detection.
FE: Is operating, adjusting and maintaining this equipment easier now than say five years ago? If so, how?
Studwell: Operating the X4 x-ray system is easier than ever before. It is a Windows-based system with a color touch screen interface. It is a bi-directional, user-configurable system that can be networked to existing plant integration systems. With the capability to store up to 10,000 unique product profiles, the X4 will auto-calibrate and is ready to run in less than 30 seconds. This is great for processing lines or co-packers that have frequent product change-overs.
Secure access prevents unauthorized access with unique password protection. This feature prevents tampering with data and thus improves compliance for both internal and external audit reporting.
The X4 also hosts an icon-driven, context sensitive user manual for easy navigation and troubleshooting throughout the system. User manuals and operator controls come in over 20 languages, promoting operator flexibility.
The operator screen comes equipped with a performance validation countdown timer to assist with HACCP compliance.
The X4 series is flexible, designed on lockable caster wheels for easy maneuvering during cleaning. The entire system can be easily removed from the line for a thorough cleaning as well as individual components for an even more thorough cleaning as typically seen in harsh wash down environments.
The X4 series is built using 304 stainless steel, #4 polish finish and incorporates Allen Bradley controls.
FE: Can X-Ray detection be used to track the source of a contaminant or missing product?
Studwell: With a solid plant integration system such as SCADA and HMI as well as an accurate, detailed data management package, users can analyze batch data to determine the source of a contaminant or missing product. In order for this process to work correctly, the product must be run on a fully integrated line.
Recent enhancements with integrated optical systems can read barcodes to more accurately determine the source of a contaminant or missing product.
FE: Are users of your X-Ray equipment including this technology in their HACCP standards?
Studwell: All X4 x-ray inspection systems are designed and engineered to meet HACCP standards. From the high quality of materials used to the integration of controls and data management, the systems make is easy to conform to regulatory standards.
FE: Are users of X-Ray technology replacing metal detectors or camera-based optical systems as the primary means of product or package inspection, or combining them? If in combination with other inspection equipment, tell me how they work together.
Studwell: The type of inspection used in processing facilities often depends on the application. Metal detection is still the primary means of product inspection. However, we are seeing a trend toward the combination of x-ray inspection with traditional metal detection as a proactive measure of additional protection.
How they work together again depends on the application. Metal detection could be used at the beginning of the line to detect contaminants on unpackaged products. This inspection measure identifies any metal contaminants prior to packaging that may have occurred during raw material transportation or product assembly. In situations where the end product goes through various stages of processing, you may see an x-ray system at a further point down the line, typically for inspection after packaging. You almost always see this when the product needs to be inspected after packaging and all or part of the packaging contains foil or metalized film.
A great example of this is beef jerky. The beef jerky is inspected for metal contaminants then once packaged and the oxygen absorber is added, the entire package is passed through an x-ray inspection system. The x-ray can verify through image processing software that the oxygen absorber is present as required.
FE: Overall, would you characterize market use of X-Ray as still a nascent technology, one experiencing steady growth, or already at fully maturity?
Studwell: Over the past decade, x-ray inspection technology has grown at a steady rate. In the past 3 years, however, the technology has become more recognized and accepted by the U.S. market. It is gaining more and more momentum as officials in the food industry recognize the potential and importance of x-ray technology to food safety and food quality.
FE: What would you say is the biggest impediment to X-Ray adoption today?
Studwell: Perhaps the biggest impediment to x-ray adoption today is the breadth of depth of technology advancements. There are a great many features and capabilities of x-ray technology that far extend past tradition inspection systems. With a variety of support mechanisms available including ongoing training, technical support and integrated user manuals, many food processors are embracing the technology more and more.
FE: What’s next for X-ray or vision systems?
Studwell: X-ray inspection systems have become more reliable over the past decade.
-compliance reporting, suppliers, not just metal contaminants, cost of ownership – scan UPC codes for easy product changeover