Overnight brewing, good or bad?

[Muadeeb]

Being in a hurry last night to get home and start handing out candy to the trick-or-treaters, I left a teapot some Shan Lin Xi brewing overnight at work. I gave it a taste this morning, strong but only a little bitter, not bad. Any reason I should avoid drinking a 15-hour brew? I know some of you enjoy it. I don’t think bacteria would have a chance to take hold, but I’m curious to hear some thoughts.

The other, more interesting thing I noticed is that the long brew added some slight but noticeable patina to the inside of the pot. I’ve been using this particular pot for 6 months pretty much every day and it’s developing nicely, but maybe this is a way to season it even faster. When I season a new pot, I boil it with tea for an hour and then leave it sitting on the stove overnight so I guess it’s the same thing as that, but it also feels like cheating a bit.

[entropyembrace]

If it tastes good it's probably ok

Even if there are bacteria growing in it (there most likely is) they're probably not pathogenic.

[yalokinh]

I do it with coffee all the time!
If you aren't getting fatally sick, then I think its ok haha

[Evan Draper]

Sure, I do it occasionally, but only to get the very last bits out. When I've overbrewed a tea earlier on in its "infusion cycle," it may not taste bitter so much as give me a stomachache.

[wyardley]

I've had people tell me that it's Ok for certain teas but not for others, but none of them have really elaborated. Probably depends a bit on the tea, as well as how hot / humid the environment is, in terms of the possibility of mold / bacteria growth.

I don't think it's likely to be bad - and I've done it before, but personally, I like to drink my tea hot, so I don't usually do it unless the tea is really rare or special.

[Poohblah]

I've had people tell me that it's Ok for certain teas but not for others, but none of them have really elaborated.

Two summers ago I experimented quite a bit with room-temp and cold overnight brewing with the goal of having a cool brew of tea in the mornings. I would say the same thing that you mentioned here: "It's good for some teas but not for others." However, this seemed to depend on the particular tea and not the type of the tea. For instance, a particular medium-roast TGY that I had at the time always turned out quite well, strong and flavorful, but I couldn't always coax the same result out of other green oolongs. Usually the green oolongs just made the water slightly sweeter. Black teas were all over the map: some ok, some offputtingly bitter, some barely flavored the water at all. Whites and greens usually turned out bitter unless I started with used leaves.

In the end, I found the whole process to be too much of a hassle, because it involved remembering to start a brew the night before I wanted it, and because it took a lot of effort and many nights of brewing just to figure out which of my teas worked with overnight brews and which didn't.

In general, I've found that overnight brews with used leaves, whether the water starts out hot or cold, rarely turn out bitter, but often rather flavorless. Starting with fresh leaves, you are more likely to get a flavorful brew, but also much more likely to end up with something bitter or unpleasant. And, as always, higher quality leaves means better tea, even if it's long/cold brewed.

[tingjunkie]

It's very rare that I don't overnight brew my teas (after many previous rounds of course). The only teas that are sometimes not so great this way are cooked puerhs or cooked liu an. Health-wise, there won't be any problems though.

[chrl42]

depends on the teas, the clays of pots and which season.

I'd trust my or your sense and body reaction if to judge the situation tho.

[Neist]

I'd like to think it's like eating leftover pizza the next day.

It's probably not the wisest of ideas, but everyone does it, and I've never heard of anyone dying from it.