Silicone and petroleum found in McDonald’s fries | March 22, 2025

“Potatoes, thank goodness! That’s a good start,” exclaims former Mythbusters host Grant Imahara, before listing the 13 other ingredients that go into a humble McDonald’s French fry mix. (Source: Dailymail)

The TV star visited the fast food chain’s potato processing plant in Idaho, USA, to study the manufacturing process from start to finish.
During his research, he learned that the potatoes were fried twice.

He also discovered that dimethylpolysiloxane – a type of silicone normally found in modeling clay – was used in the production of McDonald’s fries, as well as a petroleum-based chemical called tertiary butylhydroquinone (TBHQ).

For safety reasons, dimethylpolysiloxane is added to prevent foaming in the cooking oil.

Tertiary butylhydroquinone (TBHQ) is a food preservative.

Another surprising ingredient: sodium pyrophosphate, an additive (found in household detergents) that can cause digestive problems in high doses.

There is also a beef flavor. While this ingredient is not a problem, you may be wondering what it is doing in fries. Is it used to mask an unpleasant taste? Also, the presence of this additive carries the risk of scaring off vegetarians who thought they were eating plain potatoes.

Grant explains that there are many steps involved in making McDonald’s fries.

We first harvest the potatoes in the fields. The tubers are peeled, cut and blanched.
They are then driven at over 110 km/h through a cutting grid, which gives them the shape of their stem.

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