why does bottled water have an expiration date?

Answer 1

Volatile plasticizers and odors absorbed by the plastic leach out into the water, giving it a chemical taste after many months. You can buy reusable Nalgene (Lexan) bottles that don't that do that, but they are too expensive for disposable packaging.

Answer 2

Water is not chemically pure as you would think of it. Although the main substance is H20, it is actually a solution of water and other subtances that either were in the water originally and not remomved by a filtration process or were added (such as floride or sodium benzine). Distillition, or the process of boiling water to extract its more pure form, often removes nearly all biological material in the water. However, there is some air in the bottle and mold and fungus can multiply in the right conditions. This is how water aquires a stale taste.

Answer 3

This is more of an engineering question. A seal is not perfect. There is a reasonable expectation that there will eventually be a breach in a seal. The breach would be enough to allow bacteria, germs, etc in after a certain amount of time. The expiration date is the date that you could have a reasonable expectation that nothing would get in if it was consumed by that time.

Answer 4

maybe because of it being in a little space, if you leave it too much time on a normal temeperature the organisms on the air inside the bottle will settle down in the water and start growing, and that is when the water tastes like: yuck!

Answer 5

It contains micro-organisms which consume the o2 dissolved, as well as other nutrients, and excretes co2 and other substances like nitric excretions (urine is the human being´s nitric waste) which can alter the water´s taste and also be bad for your health.

Answer 6

It's just a sell by date.

Answer 7

Churning is good for sales.