A carbonated beverage is packed full of dissolved carbon dioxide gas, which forms bonds with water. While the soda is in the bottle, the gas is kept in solution by the bottle’s pressurized conditions. When you pour some soda into a glass, some gas escapes and forms foam, but most stays trapped by the surface tension of the water. But all those gas bubbles want to escape, making it no wonder that soda makes you burp!
To create bubbles, the carbon dioxide needs to interact with itself, which means that the carbon dioxide’s bonds with water in the Diet Coke must be broken. A Mentos candy can help with this. Although the candy may look smooth, if you looked at it under a microscope you’d see tiny bumps coating its entire surface. This rough surface allows the bonds between the carbon dioxide gas and the water to more easily break, helping to create carbon dioxide bubbles and cause the classic eruption. The speed at which the Mentos falls through the soda can affect how large the eruption is, and this can be tested by comparing whole with crushed Mentos, the latter of which are less dense.
As the Mentos candy sinks in the bottle, the candy causes the production of more and more carbon dioxide bubbles, and the rising bubbles react with carbon dioxide that is still dissolved in the soda to cause more carbon dioxide to be freed and create even more bubbles, resulting in the eruption.
In March 2004, the FDA proposed to require the full number of calories to be placed on the front of food packages likely to be consumed by one person, like a 20-ounce soda for example (see figure). A 20-ounce soda is 275 calories, not 100.
If Coca-Cola followed that FDA proposal, a label of a 2-liter bottle would have to say 800 Calories right on the front of the package.
This idea got stuck in Bush administration but there’s a good chance the new folks at FDA might take it up again.
The Coca-Cola Company is the world’s largest beverage company, refreshing consumers with more than 500 sparkling and still brands and more than 3,800 beverage choices.
Is Coca-Cola serious about helping people avoid obesity? If so, maybe it could send out a press release distancing itself from those consumer-unfriendly ads run by the Center for Consumer Freedom (see previous post).
Here’s another question: Does Coca-Cola fund the CCF directly or indirectly through the American Beverage Assocation or some other industry trade group? I will believe that they might really have an interest in consumer health when I know they have no connection whatsoever to CCF and its current ad campaigns.