Laser Guards Against Attack of Killer Potoatoes
Word of French fries and potato chips causing cancer may have made the world a darker place, but a bleeding edge spectroscope
uses light to make your fast food safe (ish) again.
by John Hitch
Not all potatoes deserve to be peeled, sliced, and fried. That may sound in- credibly unfair to any dirt-born spuds
with lofty goals of growing up to be golden
brown French fries and being slathered in
ketchup (or mayonnaise for all you metric users). But some of these root veggies conceal
a dangerous secret: cancer-causing agents
that only come out when it’s really hot.
The alleged carcinogen in question, acrylamide, forms when the amino acid asparagine in food is heated above 248° F (120°
C). The World Health Organization can’t say
for certain if it leads to cancer, but tests
on rodents and research relating to breast
cancer suggest a link. And potatoes, when
fried or turned into chips, appear to have the
highest concentration of acrylamide.
This doesn’t mean you’ll have to second-guess your decision to super-size your
burger combo. The Belgians, who thankfully
aren’t remaining neutral on the subject, have
come to the world’s rescue. After four years of
research and experimentation, a team at the
University of Brussel’s photonics lab (B-PHOT)
have produced a non-invasive optical spectro-
scope application that can identify the
acrylamide precursors at incredibly high
speeds and kick them off the conveyor
before being processed.
“The main achievement was the pre-
diction of which raw potatoes would give
rise to excessive acrylamide formation
during frying, instead of detecting the
acrylamide in the French fries them-
selves,” says Lien Smeesters, who de-
veloped the optical innovation at B-PHOT
while working on her doctorate. “It’s not
visible with the naked eye. [Acceptable
and unacceptable potatoes] look exactly
Previous methods to root out the po-
tentially killer potatoes are not as accu-
rate and potentially reject usable food.
“Chemical analysis only screens
After the automatic peeler and slicer has
part of a batch,” says Smeesters of the
previous method, which would accept
an entire batch if a small potion passed
inspection. “We scan all the food products,
because it is non-destructive. And we can
scan a few [metric] tons per hour. It’s really,
The optical scanner has been integrated
into a Tomra peeling and sorting system. The
manufacturer’s equipment processes 75% of
the global fry supply at volumes from 1,000
to 50,000 kg/ hr.
its way with them, a batch of raw taters rides
a conveyor belt before tumbling in a free fall
area. At this point, the laser scanner targets
all fries with spatially resolved spectroscopy,
scattering when hitting bad tissue. When the
system detects a bad potato, a pneumatic
air gun blasts it off the belt into a reject bin.
Presumably, these are then fown to the
Island of Misft Fries, although they can also
be processed at temperatures below the
threshold to become mashed potatoes.
The system is still a few years away from
commercialization, currently between proof of
concept and prototype, Smeesters says. Her
spectroscopy work has also led to the better
detection of carcinogenic mycotoxins. Future
food applications for this include grains, corn,
rice, and nuts.
These detection methods will work best the
earlier they’re used, typically on raw materials
right from the farm, Smeesters notes.
“If it can be removed early in the food
chain, the manufacturer doesn’t have to
spend the processing costs and time on food
that is contaminated.”
Smeesters, winner of the Photonics21
Student Award and a fnalist for the global
Edmund Optics Education Award, hopes the
tech will one day be scaled all the way down
to personal kitchen use.
“One day we envisage a world where tox-
ic French fries will be a thing of the past!”
For more info on this technology, email:
Tomra’s Helius Sorting System