Fast food has undoubtedly taken over the world as an omnipresent food source for billions, but what’s happening inside people's stomachs with each bite of burger and fry? UK chemistry professors from the University of Nottingham decided to put a cheeseburger to the test inside their laboratory, and the results are stomach-churning.

The video “A Cheeseburger in Hydrochloric Acid” shows one of the University of Nottingham’s chemistry professors unwrap a newly purchased McDonald’s cheeseburger and dip half of the burger into the hydrochloric acid in order to mimic the stomach.

The University of Nottingham has over 64 million views on its YouTube channel “Periodic Table of Videos,” and the most recent of its over 500 videos about each element on the periodic table is hydrochloric acid.

"As you're watching me, churning away in your stomach is acid, which is one of the first stages in which food is broken down into usable components to give you energy or to make you fat," Martyn Poliakoff, a chemistry professor at University of Nottingham, said in the video. “Because hydrochloric acid is found in everybody’s stomach and it’s part of our digestive process.”

Hydrochloric acid is a strong compound naturally produced in your stomach designed to break down food, and it's strong enough to eat right through a piece of wood if you dropped it into a concentrated vat. The reason the stomach doesn’t digest itself is because it’s protected by epithelial cells, which secrete a rich solution to coat the stomach walls. The continuous supply of solution protects the stomach and keeps a balance in order to avoid the overproduction of acid.

Hydrochloric acid is a strong mineral acid used in many industrial fields as a chemical to remove steel, neutralize water, process leathers, purify salt, and balance pH levels. It’s highly corrosive, which is why it’s a surprise to find the burger won’t break down inside the laboratory. After three and a half hours hovering halfway into the concentrated hydrochloric acid, the container became thick with black liquid from the burger but was not fully broken down.


It takes about 24 to 72 hours for most people to digest food. However, because hamburgers are a fattier food, it can take up to three days to fully digest, according to research by Dian Dooley, an associate professor of Food Science and Human Nutrition at the University of Hawaii at Manoa. A fruit salad, on the other hand, only takes 30 minutes to digest because it’s easier for the body to break down water-laden fruits and veggies.

Demonstrating the indestructibility of the McDonald’s burger has become an Internet fad, with experiments like the Happy Meal Project, which prove McDonald’s burgers and fries maintain their original condition after six months.

It’s the fat inside the burger patty and cheese that preserves the food and keeps it in pristine condition. High-fat concentrations means it doesn’t have a lot of water, unlike the easily digestible fruit salad, so it doesn’t break down or give mold anywhere to grow.

The University of Nottingham professor confirms such biochemical science when he observes the end result of their experiment. He said the fats weren’t going to dissolve very well because in the body there’s bile acids used to break down the fats, meanwhile they only used pure hydrochloric acid to mimic digestion.