PET Food Processing - June 2018 - 37



Inline detection equipment offers more benefits than product safety.
By Jennifer Semple |


Foreign body contamination in pet food or pet treats can
have far-reaching effects. Metal detection and x-ray systems are most often employed at the end of production to
inspect finished, packaged product, but the additional use
of this technology further upstream protects more than
product safety. Catching metal and other foreign objects
early can protect expensive processing equipment from
damage and eliminate an item before it's fragmented into
smaller parts that are more difficult to detect and remove.
Inline detection upstream can also identify contaminants
before more processing resources have increased the value of the product.
"If you catch a metal contaminant in its largest form
at the start of the processing line, you are eliminating
it at the cheapest part of the process," explains Steve
Gidman, president of Fortress Technology, Toronto,
Canada. "Pushing the inspection solely to the end of the
line, any contamination will be caught at the most expensive part of the production process where an entire
batch of product could potentially be contaminated with
unidentifiable metal fragments. At this point, the cost
to a business and brand reputation could be considerably higher." Upstream detection complements the endof-line systems by rejecting the metal and often smaller
quantities of product before it's fully packaged.
Large-bag inspection systems for fully packaged
products are commonly used for dry, kibble applications. Upstream, pipeline metal detectors work best for
processed liquids, pastes and meat slurries, and x-ray
systems can inspect metalized packaging and detect
non-metal contaminants such as glass or bone.

as they contain added vitamins, minerals and colorants
with oxides," explains Ray Spurgeon, product manager,
Eriez Magnetics, Erie, Pennsylvania "In sufficient levels,
these ingredients create conductivity and what is called a
'product effect,' making foreign metal objects more difficult to detect." This is also the case with wet products
because moisture equals conductivity.
Packaging materials common in pet food and treat
processing also challenge inline detection technology.
"We are seeing an increase in metalized film packaging,"
says Robert Rogers, senior advisor for food safety and
regulation, Mettler-Toledo, Lutz, Florida. "X-ray inspection systems can be used for these types of packages as
well as for metal cans."
The vast majority of inline detection applications in
pet food involve post packaging inspections. "Package
styles are diverse, and many of our products are aligned

Conducting performance
tests on pipeline metal
detectors that inspect wet
pet food can be challenging and time consuming.
Fortress Technologies

Needle in a haystack
Metal detectors create a balanced electrical field and
look for a very subtle change in that field. "The challenge
is pet food and treat products can often be conductive | June 2018 | PET FOOD PROCESSING


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