We all love a McDonald’s once in a while and let’s be honest, their fries taste great, but how much do you know about what actually goes into them? Former Mythbusters host Grant Imahara travels to the company’s manufacturing plant in Idaho, US, to see the production process from start to finish and finds out.

During his investigation Imahara discovered that McDonald’s French fries contain 13 ingredients, including dimethylpolysiloxane (a form of silicone found in Silly Putty) and petrol-based tertiary butylhydroquinone (TBHQ). He also found out that the fries go through not one, but two rounds of frying.

According to Imahara’s report, there are numerous steps involved in the creation of McDonald’s fries as well as numerous ingredients (thankfully including potatoes).

First potatoes are harvested from fields before being peeled, cut and blanched.
They're then fired through a cutter at up to 70 miles an hour into thin sticks.
After being chiseled into the perfect shape, the strips of potato are sauced with a blend of canola oil, soybean oil, hydrongenated soybean oil, natural beef flavor, hydrolyzed wheat, hydrolyzed milk, citric acid and dimethylpolysiloxane.
Dextrose - a natural sugar - is sprayed on the batons to help them maintain a golden fried color.
Sodium acid pyrophosphate is also added to prevent the fries from going grey.
Last but not least, salt is sprinkled on for flavor.
The fries are then flash frozen at the Simplot factory and transported to McDonald's outlets across the country.
Once they are at restaurants, the potato sticks are fried for a second time.
The oil blend is similar to the factory mix, with the addition of tertiary butylhydroquinone and hydrogenated soybean oil - a manufactured form of trans fat.
And voila! McDonald's World Famous Fries are served.