McDonalds french fries are made from potatoes that have been washed, steam peeled, blanched, dried, then par-fried, seasoned, and frozen. So, they are fried twice. This is the first frying prior to freezing.
French Fries:
Potatoes, vegetable oil (partially hydrogenated soybean oil, natural beef flavor (wheat and milk derivatives)*, citric acid (preservative), dextrose, sodium acid pyrophosphate (maintain color), dimethylpolysiloxane (antifoaming agent)), salt.
Notice the parenthesis (shown in red). This shows that all those additives are in the oil and not put on the potato. Thus, we really only have three ingredients. Potato, oil, and salt. But let’s look at the whole list anyway.
Potatoes are simple.
Now for the oil:
vegetable oil (partially hydrogenated soybean oil) - Soy bean oil that has had hydrogen added to it to make it a partially saturated fat. This makes it solid at room temperature and more stable with a longer shelf life. It’s a trans fat and is used to fry the potatoes the first time.
natural beef flavor (wheat and milk derivatives) – animal proteins for flavor, think powdered beef bullion. This is added to the oil and not the potato.
citric acid (preservative) – an extract from citrus fruits. As a preservative, it acts as an antioxidant and it is added to the frying oil, and not the potato itself.
Dextrose – sugar, it’s added to the oil and not the potato.
sodium acid pyrophosphate (maintain color) – another antioxidant (preservative) that is added to the frying oil and not the potato itself.
dimethylpolysiloxane (antifoaming agent) – this is antifoaming agent that changes the surface tension of a liquid preventing bubbles from forming. This is useful when frying as you don’t want the oil to boil over. This is added to the frying oil and not the potato itself. This chemical is also used in medicines that treat you for flatulence and intestinal gas.
And finally, the third ingredient - Salt = sodium chloride....this is put on the potato after frying.
So, we have potatoes, fried in oil, then flavored with salt. Technically, not too different from the way anyone makes a french fry at home – fry it, season it, and serve it.
The only exception being the preservatives in the oil......and those things may be in the oils we’re using at home anyway. Not to mention that those preservative items can be found in citrus fruits, baked goods, and gas relief medicines.......all very common things.
This is the second frying in the restaurant:
Prepared in vegetable oil ((may contain one of the following: Canola oil, corn oil, soybean oil, hydrogenated soybean oil, partially hydrogenated soybean oil, partially hydrogenated corn oil with TBHQ and citric acid added to preserve freshness), dimethylpolysiloxane added as an antifoaming agent). *CONTAINS: WHEAT AND MILK (Natural beef flavor contains hydrolyzed wheat and hydrolyzed milk as starting ingredients.)
So again, it's just oil. And the last part is a * note from above.
The oil is a blend of regular unsaturated oils and unsaturated oils that have had hydrogen added thus turning them into trans fats (a partially saturated fat) so that they are solid at room temperature and have a longer shelf life.
So, what we have is a special oil they use for frying. It’s an oil that has preservatives in it to help it last longer, it has flavoring added to it, and it has been treated so that it will not foam up.
In that oil, a regular potato is fried and then seasoned with salt. So, the only real ingredients here are Potato, Oil, and Salt. Not that weird really.