Dissolved gas release from liquid

I wish I could directly embed this video here

https://youtu.be/Syb3MHtjojQ

It can be seen that no external chemical has be put into the bottle, so the bottle content has clearly not been modified.

A friend of mine said it must be capillary action, but it doesn't look like it one to me.

It's doesn't look normal CO2 release either, since it flows steadily for 40+ seconds.

Assuming no battery/pump has been attached to the straw, how can this be explained scientifically?

• you used the experimental-physics tag ... did you actually perform an experiment to determine the cause of the fountain effect? Jan 4 at 20:39