When you brew coffee, there are oils in the coffee that will break down and give the coffee a bitter flavor after about 18 minutes of being heated. I can only imagine that reheating cold coffee will produce the same or similar result.

I dislike coffee that's been kept hot - to me it tastes burnt. I think it tastes better if I let it get cold and nuke it as I need it. But it tastes even better to use the espresso machine and make one cup at a time.

I have only ever reheated coffee once and it tasted odd,so i have never done it since:)

Supposedly the longer it stands the stronger it gets. So if it is cold and reheated, it might be too strong/or bitter and not as pleasant as a freshly brewed cup of coffee.:)

Never heard that before, but there is nothing like freshness !!! Nice to see you J!

I've been thinking. Who says not to reheat coffee? I suspect it's folgers/maxwell house/hills etc.. They would all much rather you threw away cold coffee and made fresh. There is no profit in reheating cold coffee.

They say it can make it bitter, but I reheat my coffee and it always tastes the same.

There is a saying in Austria. "Kalter Kaffee macht schön", which means "cold coffee makes you more beautiful". That's is usually the reason why people encourage others to drink it cold. I had lots of cold coffee in my life...and it's working...lol

It is said the benefits of coffee are best within 15 minutes of being brewed. I reheat mine a lot. I don't drink it for health.

It changes when you reheat it and never tastes as good as when it was first brewed. It breaks down and gets bitter and the oils separate. But if you just made instant coffee, go for it.

Because it tastes like bitter crap !! :)

I can't see any harm in it except that it gets really nasty tasting when reheated. Fresh coffee is the best kind. (any brand)

I was told some components oxidize but I do not know if it is true.

Hi -Freedom Issues-, Taste aside, as suggested above, another reason that people may say not to reheat coffee (especially in a microwave) is that it cannot boil. Thus when reheated, coffee can in fact become much hotter than it appears, as it has no way of dispensing that heat as would normally occur when a liquid boils.

It tastes terrible.

Because it develops the taste and consistency of toxic waste. :-)

I don't think it's hazardous to do so, and it becomes even stronger, however it will certainly taste like corpse. But, don't reheat it if there's milk or cream in it already...

I HAVE BEEN REHEATING COFFEE FOR YEARS. WHEN I WAKE UP I HIT THE BUTTON ON THE COFFEE MAKER TO HEAT UP THE LAST 2 CUPS I LEFT IN THE POT THE DAY BEFORE - I DONT PUT IT IN THE FRIDGE - I FIGURE IN 20 MINUTES SITTING ON THE BURNER IT GETS HOT ENOUGH TO KILL ANY BACTERIA THAT COULD GROW IN THERE... THESE TTOO CUPS ARE STRONGER - MAYBE A LIL MORE BITTER - BUT THEY WAKE ME UP - AT LEAST ENOUGH SO I CAN START A FRESH POT... I DRINK COFFEE ALL DAY UNTIL ABOUT 5 OR 6 - 5 HOURS BEFORE I GO TO SLEEP. USUALLY ABOUT 12 8 OZ CUPS A DAY. I DON'T BELIEVE I HAVE EVER GOT SICK FROM DRINKING COFFEE - THAT SAT FOR A DAY THAT I REHEATED. BESIDES - IT MAKES YOU APPRECIATE THE FRESH COFFEE EVEN MORE - BUT I JUST DONT WASTE MONEY... I DONT THROW OUT ANY FOOD - EXCEPT THE MAYBE THE BONES I BOIL TO MAKE SOUP AFTER A FEW MONTHS. YOU CAN SAVE HUNDREDS AF DOLLARS A YEAR - I EAT EGGS ORANGES COFFEE ORANGE JUICE WHOLE CHICKENS RICE BEANS PEANTUT BUTTER OATMEAL TEA TUNA BREAD POTATOES ONIONS... MY MAIN WASTE IS COFFEE GROUNDS ORANGE PEELS AND EGGSHELSS - ALL GREAT FOR THE GARDEN AND ATTRACKED BIRDS. BY EATING THE FOOD ABOVE - I HAVE LOST WEIGHT AND AM EATING MUCH HEALTHIER THAN WHEN I HAD MONEY TO BUY OUT , DRIVE THROUGH - AND TV DINNERS. I PROBABLY HAVE CUT MY FOOD BILL DOWN FROM 600 A MONTH TO ABOUT 100 I USE THE COFFEE CONTAINERS - I GET FOLGERS AS STORAGE CONTAINERS. I USE THE BAGS THE GROCERIES COME IN AS MY GARBAGE BAGS. TRY NOT TO WASTE ANYTHING. I AM CURENTLY CONSTRUCTING A LAUNDRY BAG OUT OF THE RED PLASTIC MESS BAGS THE ORANGES COME IN. I LEFT THE CITY AND MY $1500 A MONTH HOUSE PAYMENT FAR OUT INTO THE COUNTRY. THE BIRDS ARE AMAZING. CARDNIALS - BLUEBIRDS - HUMMING BIRDS - RED TANAGERS - I CAN SEE COWS FROM MY WINDOW. THE AIR IS FRESH AND CLEAN. ITS BEAUTIFUL. MY RENT IS $270. I SELL MY WORN CLOTHING TO PEOPLE ONLINE THAT HAVE A FETISH - AND IT PAYS FOR MY FOOD AND RENT. PLUS I NEVER HAVE TO DO LAUNDRY AND AM ALWAYS BUYING NEW CLOTHES.

Never heard of it. I reheat coffee all of the time in the microwave. I shut it off right after I make it so that it doesn't get strong and bitter.

I did not know that as I di it a lot.

It changes the taste dramatically. Especially, if you reheat in the microwave. Its either fresh or none at all.

It just doesn't taste as good

to me it does not have that same fresh taste, however i have learned to like unfresh coffee. I reheat my coffee all day, because i drink coffee all day and can not afford to make a fresh pot or buy a fresh cup everytime my coffee gets luke warm.