Self-correction in gaiwan steeping

One of the things that I wasn't expecting about gongfu brewing with a gaiwan is that it's actually pretty forgiving (which, on the other hand, also makes it harder to predictably and significantly alter the results by tweaking variables in the process).

The extremely low thermal retention of thin ceramic (even when preheated) means that there is a rapid dropoff in extraction efficiency over time. Especially since there is also such a small amount of water being used to extract such a high amount of leaf; the more stuff is in the water, the less quickly the rest of the stuff in the leaves is going to be pulled out. So the relationship between time and extraction efficiency is not linear and is significantly different from in western brewing, where heat is lost much more slowly and the water is a more efficient solvent for longer in the process.

I think this may be part of the reason why there's so much variation in advice on how long to steep tea as a baseline when brewing this way. It's harder than you might think to either undershoot or overshoot. But this also means that if one does want to vary the result, bigger swings in the input variables may be needed.

I imagine the temperature aspect of this would be less true when using a thick-walled teapot, although I don't have an appropriately sized one to try currently. It would be entertaining to try using a small double-walled thermos and see how much it messed up my steeping times. I wonder if they even make, like, 200ml baby thermoses.

Non-transferability of results between methods

Another thing that I suspect may create confusion on initial steep lengths in particular is variability in ratio. It seems like most people who are doing gongfu brewing are not weighing their water, even if they do weigh their leaves. This makes it likely that the amount of water used differs substantially from steep to steep as the volume of the vessel occupied by the leaves changes substantially due to rehydration. It can take several steeps for the leaves to reach their peak volume.

(This is also not getting into whether people are actually timing with a watch, casually timing by counting, going by color/smell of the liquor and changing steep time on the fly, etc. For the most part I don't make a significant effort to be precise and repeatable when using a gaiwan either, because it's simply not fun to continually faff with time and weight measurement while you're trying to enjoy your tea. It's different when you can frontload the faffing and get it out of the way all at once, then drink your tea after.)

For me, the main upshot to this is just that the inputs and results in one brewing method may be even less transferable to another brewing method than I initially thought. For context, when I do stacking of different-length brews, I'm using a plastic brewer with less heat loss, and doing back to back steeps with weighed water. That brewer is also a larger vessel (meaning that if the leaves expand beyond the size of a gaiwan, the vessel doesn't create a limit on the amount of water that can be added). It also has some other quirks, like increased retention of steeped tea due to using a bottom dispensing mechanism.

(This thought process also significantly increases the risk that I will end up buying a valved coffee dripper and try to use it to make pourover tea, lol. If that happens I'll also probably end up buying a scale that measures flow rate.)

Why does tea taste better to me in a thermos???

Not directly related (well, probably), but another source of consternation for me when comparing the results of different tea brewing methods is that in many cases, I like my tea a lot more after it's sat in a thermos for 30 to 60 minutes. Hard to say why. It's not just a temp thing, or else I'd get the same enjoyment by cooling tea more quickly in a non-insulated vessel. (Which does certainly make tea taste better than when it's scalding hot.)

It could certainly be psychological, I may just derive more enjoyment from nursing a large drink over a long period. Other than that, my best guesses would be

• reduced loss of aromatic goodies due to being covered and having a proportionally much smaller surface area exposed to air
• gradual continuing extraction of small leaf particles
• some additional chemical stuff going on amongst the junk that's been extracted? seems unlikely