X-ray inspection machines are being moved up the production line in some food factories, according to Eagle Product Inspections.
The firm said customers are seeing the technology and the different things it can do besides contamination testing and thinking about moving it closer to the source of production.
Kyle Thomas, strategic business unit (SBU) manager, said x-ray machines have traditionally been placed at the end of the line.
“They have been the final quality control and assurance check before product goes onto the truck but customers are realising they do more besides contamination, like quality attributes of the product you have,” he told FoodQualityNews.com.
“Customers see the technology and the different attributes and say ‘maybe I can move the inspection point closer to the source’.
“If there is a problem, this gets it off the line before it becomes a big problem and if it is a non-contamination issue such as weight it can go back through a re-work lane.”
Thomas said the closer to source move, places more demands on machine to machine and machine to control integration and the data handling side to feed quick business information to make processes better.
“It is generally done when a line is configured or re-configured for new products or a new packaging style such as paperboard to pouch.
“On an existing system with four walls and not much space there is less chance to do this.”
X-ray can check a variety of things other than contaminants, said Thomas.
“It can do missing component detections, for example if you are supposed to have five items in a pack and it could only see four it would be rejected. If there is inconsistency in the product, it is damaged or mis-shapen it will spot that.
“The product should look like the picture on the package, if it shows a cookie the product should look like a cookie.
“It quickly attributes other things included in the package, we do a lot of work with the fruit and veg industry with salads that have a lettuce leaf, kit, croutons and salad dressing in the pack.
“It looks for the kit inside the package and checks if the integrity is right for the number of products and if the different items are there and in the right place.”
A fine line
He said there is a fine line between throughput specifications wanted by customers.
“The tolerance between items is being tightened, for example a firm wants to run 400 packs per minute but wants half a millimetre on aluminium that is a challenge because if you had a slower system you have more scan time with the product but that is the trade-off between speed and sensitivity.
“There is also the issue of physics, a rule of thumb is if it floats in water you won’t detect it in x-ray, such as plastic, rubber and low calcified bone in poultry or fish bone present challenges. That is the holy grail and some can be detected if you slow the process down but then it is not economically viable.”
He said the firm’s dual energy process goes a long way to addressing difficulties.
“I go back to the salad kit, it has romaine lettuce and is a busy image, making it difficult to determine where the kit is.
“MDX technology uses chemical values to discern between organic and inorganic matter.”
He said work was being done to expand Material Discrimination X-ray (MDX) technology to different applications.
Thomas compared MDX and single image x-ray to the difference between regular and high definition television.
He said its Fat Analysis business was a focus of resources, application expertise and development work.
The business features equipment designed for the meat industry to test for fat content, chemical lean contaminants, calcified bone in cartons and in bulk mass.
Thomas said it was a huge area of development and the firm was working with channel partners to provide them with the tools and training needed for customers.