If you found this in your teenage niece’s closet, it’s understandable that you stopped and wondered what on earth you were looking at.
At first, it looks almost like someone turned a bottle of apple juice into a bizarre science experiment.
And honestly, that’s not far from the truth.
The setup in the photo—a bottle of juice with a balloon fitted tightly over the opening—is commonly associated with fermentation.
So What Is the Balloon Doing There?
During fermentation, microorganisms such as yeast can consume sugars and produce carbon dioxide gas.
