When drinking soda, it always burns if you drink too fast. But when it gets flat, the burning goes away. What is it about the combination of air and sugar water that creates the burning sensation??
Carbonated water is carbonic acid, chemical formula H2CO3. I’m not sure if it burns because it is acidic, but that may be the case. Someone else can give a better answer.
There’s a bit of carbon dioxide at the very top of your Coke can waiting to escape. The CO2 also mixes with the soda during canning and becomes carbonic acid, which affects the flavor, giving it a bubbly feel and biting taste to it. When you pop the top much of this escapes, and if you give it enough time, most of it will, and you’ll have a sweeter, flatter soda.
Not to hijack the topic, but is this acid (and it’s burning) only present in the dissolved liquid state, or is it the gas? Is this the same reason for the wasabi-like burn when a soda burp comes out the nose? Why does the burp only burn out the nose and not the mouth?
It is the carbonic acid that ‘burns’ or produces the biting taste.
When you burp or belch up some free CO2 it disolves in the moisture in/on the lining of the nasal cavities and the resulting weak carbonic acid also produces the same buning sensation. Your mouth has become accustomed to the bite or burn so doesn’t notice the burp or belch as much.