After coffee is brewed, how long does the caffeine stay, and how long is it good for?

by Corrine
(Oregon)

QUESTION:

I want to know how long caffeine stays in the coffee once it is brewed. I was told it last only 20min. after it is brewed. Also there was a discuss should or should it not be thrown out after the day it's made. Some say they keep it for a couple of days to avoid waste. Can you please enlighten us.

Thank you for your time.


ANSWER:

To answer your first question, caffeine does not evaporate or otherwise disappear after brewing. There will be as much caffeine in your coffee after five hours as there is after five seconds. Arguably, there will be more caffeine, because some of the water will evaporate, increasing the concentration of caffeine in what’s left over.

As for throwing your coffee away at the end of the day, there are two ways to look at this. If it’s the taste that is important to you, then definitely you should throw it away – and after a couple of hours, not at the end of the day.

If you are anxious to save as much money as possible, you can put your leftover coffee in a sealed container, store it in the fridge, and heat it up again the next day. But don’t expect your coffee to taste as good when it is reheated.