By Yuan Ren For Mailonline
Published: 18:16 BST, 23 May 2019 | Updated: 18:56 BST, 23 May 2019
There's more to a coke can than meets the eye, a whole inner tube of plastic in fact.
A shocking video from " frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen has revealed the secret plastic coating inside aluminium cans after the metal is dissolved away with detergent.
The film is there to act as a barrier against the corrosive effect of acidic drinks on the reactive metal.
High levels of anything that has reacted with aluminium is a potential threat for bone and brain function in humans and this prevents it getting inside people.
Experts told MailOnline that the film is 'negligible' and makes up a tiny percentage of the can and is destroyed before the metal is recycled.
Fizzy drinks are filled with carbon dioxide gas, which is what gives them their bubbles.
The carbon dioxide gas dissolves in liquids forms an acid, which gives bubbling drinks like Coca Cola a high levels of acidity.
The acid responsible is normally phosphoric acid in coke and citric acid in juice based drinks like Fanta.
If this acid was in direct contact with the metal aluminium it would react with the metal and corrode it, creating an aluminium compound known as aluminium phosphate as well as hydrogen gas.
High levels of aluminium in the body can be toxic and excess levels can cause bone and brain abnormalities.
The plastic liner forms a barrier between the product and metal, providing protection against food-borne diseases.
According to Aluminium Association's website, the plastic coatings in coke cans forms a barrier between the product and metal.
'These coatings have been critical to improving food and beverage safety since being introduced more than 50 years ago,' it wrote.
These films have also been 'critical' to improving food and beverage safety since their introduction 50 years ago.
Matt Meehan, from The Aluminum Association, told MailOnline what happens to the plastic during the recycling of