Turns out, there are real spuds in the fries. As for that 17 number, that's a myth.
There are really 19 ingredients.
In addition to different oils, the list includes several chemicals that perform various functions, including ones that adds flavor, an anti-foaming agent that keeps oil from splattering, another aimed at keeping "the potatoes from going gray" and preservatives, Imahara explains.
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Imahara also takes a tour at Simplot, which supplies potatoes to McDonald's USA, with Koko Neher, a production planner there.
Whole potatoes travel on a conveyor belt before being shot through a high-pressure water tube through a grate at 60 to 70 miles per hour.
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Next up is the "ingredient dip."
"This is the ingredient dip, where we control the color, and we're adding dextrose – all natural sugar – to make sure that we get a consistent color no matter what time of the year it is," said Neher, adding that it also puts in sodium acid pyrophosphate to control "graying after freezing."