WHY does the water in the glass change its taste overnight?The first thing that affects taste is
temperature. Most of the time, people fill themselves with cool water, and
when it gets to room temperature, it doesn't taste as "fresh". However, it is an indirect cause, the main factor in the unpleasant aftertaste of water from the glass is
the gases that dissolve in the water overnight. That's why if you pour water in a bottle, it will taste less unpleasant.
Interestingly, the higher the temperature, the better the solubility. Mostly carbon dioxide enters the water, and when it dissolves it forms carbonic acid, which can lower the pH of the water.
In addition, acetone gases and aldehydes can dissolve in water.
Scientists say that even
in 30 minutes the water can get an unpleasant taste. But if you forget a glass of water for a few days... you'll get all sorts of germs in it.
