McDonald’s has finally revealed how it makes its french fries – and surprisingly potatoes do make the ingredient list.

But it’s not all good news – 14 chemicals are also thrown into the mix, one of which is petrol-based (tertiary butylhydroquinone) and another is a silicone used in silly putty (dimethylpolysiloxane).

Food mythbuster Grant Imahara was allowed access to McDonald’s’ french fry processing plant in Idaho to see the production process himself.


And in a video he reveals that the chips are created from a mix of Russet Burbank, Ranger Russet, Umatilla Russet and Shepody potatoes then are peeled cut and blanched before being fired through a cutting ‘cannon’ at 70mph.



The batons then pass through a bath of sauces, which is a blend of canola oil, soybean oil, hydrogenated soybean oil, natural beef flavor, hydrolysed wheat, hydrolysed milk, citric acid and dimethylpolysiloxane.

Dimethylpolysiloxane, which the television personality assured viewers is perfectly harmless, is used for safety reasons to stop cooking fat foaming when the fires are cooked.

The natural sugar dextrose is then sprayed on the potato sticks to ensure they maintain a gold colour and sodium acid pyrophosphate is added to stop them turning grey.

After the sticks are fried in the factory, salt is added. The fries are then flash frozen and shipped off to McDonald’s restaurants where they are fried again before serving.

Tertiary butylhydroquinone is included in the cooking oil as a food preservative.

McDonald’s french fries as a finished product contain 510 calories, 6 grams of protein, 24 grams of fat, 67 grams of carbohydrate and 290 milligrams of sodium.

UPDATE: McDonald’s in the UK have been in touch to assure readers these chemicals are only used in US stores and not here.

A McDonald’s Spokesperson said: ‘The only ingredients in our UK Fries are Potatoes, Vegetable Oil (Sunflower, Rapeseed), Dextrose (only added at beginning of the potato season) with nothing added except a sprinkling of salt after cooking. Customers can request that their Fries be served without salt.’

Advertisement Advertisement