[2muchcoffeeman]

The pressure build up can be quite a lot from fermentation. I’ve accidentally fermented drinks in glass swing top bottles. And upon attempting to open the bottle the pressure ripped the stopper and the metal parts right off the bottle at high speed.

If you were purposely fermenting something, you could build enough pressure to pop the bottle.

[christophilus]

Yep. I once had half a bottle of kefir end up all over my kitchen ceiling. After that, I always opened them outside, pointing away from anyone.

[lioeters]

> half a bottle of kefir

I also found this the hard way, once you open a bottle of kefir or yogurt and then close it again to drink/eat later, the fermentation process speeds up due to the additional oxygen, building up pressure until you open it the next time. Fortunately no one got hurt.