Something weird happened the other day.
We had a 2 liter of grape soda in the fridge, only 2/3 full.
No one had touched in for a while.
I opened it, and the lid went shooting into the air quite violently with lots of mist happening.
What on earth could’ve caused that?
We didn’t drink it.
soda terrorists?
Thank you for your helpful answer.
:dubious:
Soda goes foamy suddenly for many of the same reasons that beer does. Here’s a table of many of the physical causes of wild beer: too much CO[sub]2[/sub]: too much pressure, not enough pressure, opening the container wrong, too high a temperature etc. It’s not listed, but contamination of the beer or soda can also cause wildness. Proteins, yeasts, dust, or even a bit of powdered charcoal can all make the carbonated beverages go wild. This used to be a big problem for brewerys that shipped their beer in the days before refrigeration. One brewery, Karlsburg I believe, even went so far as to compile a periodic table of the elements, listing each element’s capacity to cause foaming. Carbon dust was particularly good at making beer go wild. Filtration technology, and good quality control pretty much eliminated the problem, but still, a bad bottle slips through once in a while.
Hey, I figured someone who had a clue would get to you eventually.
I was just keeping the thread high up on the board to make sure they’d see it. Yeah, that’s it. Keeping the thread high. Not just being a smartass. 
Chances are, when you opened it, a wild yeast got into it and started fermenting, in spite of the preservatives in the soda. Try squishing most of the air out of the bottle, put the cap back on, put it in a bucket with a towel over it and leave it out for a few days, and see what happens.
There was no foam.
We threw it out!