The fizz in the drinks are from carbon dioxide.
Carbon Dioxide
Carbon dioxide gas is used to put fizz into fizzy drinks. When pressure is released, the gas bubbles out, creating the sparkling effect in the drink.
Fizz in fizzy drinks is dissolved carbon dioxide (CO2) coming out of solution. That's all that is in fizz.
Fizzy drinks are not fizzy in space as there is no oxygen to fizz the bubbles. The fizz in fizzy drinks is carbon dioxide coming out. In a vacuum the liquid would "boil" because of the water vapour coming out, and would probably freeze because of all the heat removed with it. Oxygen plays no role in this at all.
The carbonation in fizzy drinks cause them to fizz.
The carbonic acid decomposes, causing water and carbon dioxide - you see the carbon dioxide as bubbles.
Fizzy drinks fizz because they contain carbon dioxide gas that is dissolved under pressure. When the pressure is released, the gas escapes in the form of bubbles, creating the fizzing sensation.
carbon dioxide
its all the fizz
CO2
carbon dioixide makes drinks fizz