Is Drinking Day Old Coffee Bad For You?

How long does your coffee stay good or bad? Is drinking day old coffee bad for you? There are some coffee drinkers who keep old coffee in the fridge for quite some time and then microwave it before drinking.

Coffee is usually made in the morning and if there’s something left, it is being stored either in fridge or heating it in the microwave. It is one of the widely most consume beverages in the world. But coffee doesn’t stay good forever, it goes bad too. But how long does your coffee stay fresh or let’s just say safe to drink?

Your coffee stay fresh for only 30 minutes when stored in an airtight thermos. Why so quick? Because coffee continues its oxidation process even after brewing. Its freshness also varies on the beans being used. Once you ground your coffee beans, it starts to oxidize more quickly. When there is too much contact with air, your roasted coffee beans continues to oxidize. This oxidation process causes deterioration of its flavor. Thus, when roasting your coffee make sure to store it properly so that oxidation process slows down and your coffee remains good even after a week. On the other hand, when your coffee ground is in contact with water, it will begin releasing its aromatics, oils and acids into the water. As water can absorb flavors from its environment causing change in flavor. When coffee oil goes bad, it loses its flavor and alters its taste. So your day old coffee may become more acidic. Your coffee starts to go bad after about 30 minutes when it gets cooled and eventually loses its favor and becomes more acidic.

In addition, when you leave your coffee for too long, hydrogen and oxygen reacts with each other causing rise in the pH level of your coffee giving it a bitter or stale taste. Stale coffee is not dangerous to drink but it is unpleasant to taste. But if you put milk in it, it is advice not to drink it after two hours.  So, don’t ever leave your coffee in a brewing pot for a long period of time or if you can’t drink it makes sure to store it in an airtight thermos bottle.

When it happened that you added some dairy on you coffee and leaving it unrefrigerated overnight, you should throw it away and never drink it. Why? Because dairy or milk has only less than of two hours at room temperature. So if your coffee has dairy make sure to drink it fresh. But if you refrigerated your left-over coffee without adding dairy to it, it will last for at least a week.

So, is drinking day old coffee bad for you?

It is also not advisable to reheat your coffee in the microwave though it kills some bacteria but the microwave won’t reverse the flavor of your coffee. So, is drinking day old coffee bad for you? Well, it depends. A day old black coffee is safe to drink as long as it’s refrigerated but it possibly won’t taste good. If you added some dairy in it, well better make a fresh one. If you have some leftover make it better if you’ll refrigerate it and drink it as soonest possible.

Did you know that as your coffee sits, bacteria and molds begin to grow? Yes, the presence of molds and bacteria is not only the reason why your coffee tastes bad. As your coffee sits longer, its chemical reaction changes, breaking down its delicate compounds giving your coffee a bad taste.  

Over-extraction can also cause bitterness so to avoid it, make sure that your grind size is not too small and you are not brewing your coffee for too long. Keep it in mind that coffee is like any other foodstuff, it doesn’t last forever. The older your coffee grounds are, the more it is oxidized. Old coffee grounds don’t have a rotten smell but it doesn’t have any scent. If you can’t help but make coffee more than enough for yourself, better invest in a good storage like thermos which can prolong its quality for a few hours.

These are some of points to consider if drinking day old coffee is bad for you or not. The important thing to keep in mind is there’s no health threat when drinking such old coffee but it has such unpleasant taste not comfortable to drink.