Different times of the year

It's an interesting idea. I guess it could have to do with temperature and humidity. I noticed that a medium fire Jīn Fó (金佛) that's usually at least decent tasted kind of acrid / sour to me yesterday, so maybe you're on to something.

I think your taste buds also change from day to day (I certainly notice this a lot myself), and what you eat makes a HUGE difference. I love flavorful, spicy food, but I've noticed that tea, especially certain types of tea, tastes awful after a meal that's laden with garlic and spices. I tried drinking a medium roast / medium oxidation Tieguanyin recently after such a meal, and the taste was absolutely awful. There's a reason that food tasters eat food that's pretty bland for a day or two before they have to do any serious tasting.

The thing is that when this happens I can usually find a tea that will come out fine (sometimes even a tea of the same type, like yancha), it just takes a few tries. It doesn't affect every tea at the same time (sometimes it can even just be one TGY or baozhong over another), so I really don't think it's just my own tastes. Some just simply won't come out well at all.

Now when it's really hot and humid it just makes sense. On those days I just can't get much aroma until I go into an air conditioned room. Air conditioning does resolve those issues on the very hot and humid days, so that just leaves the days that aren't hot and humid but simply produce insipid cups.

The main thing that bothers me about these times is the amount of tea I end up wasting just to find something that will work.

Don't worry, I'm not beating my head against a wall; it's just an intriguing mystery :) When I encounter a phenomenon like this I just feel compelled to investigate. That's how I got into tea in the first place :)

I get that as well.. there are days that I just can't brew a good cup to save my life. As in Stephane's response below, I've also noticed this with my mood. This phenomenon becomes even more strange, however, when you use a Zoji. With the Zoji you can be absolutely sure that so many things remain exactly the same when the results come out so differently. The water temp is kept at the same temp, the brewing vessel is in the same spot underneath, just sitting on the tray and not being held, and so on.

Yes indeed. I think I may have come across this as well, however I only ever attribute things like that to my own brewing skills.

Since starting this I've paid a bit of attention, and while it seems to happen more on hot and humid days, heat and humidity do not seem to be the determining factors. I had it happen a few days ago, but the heat and humidity were the same as later when it came out just fine. I'm tempted to find a college professor that would understand the physics of things like aroma. I have actually noticed that on these days the same can happen with the aroma of some foods as well. I'm not a "foodie," though, so it doesn't make as much of a difference to me.

Very hot and humid days, though, do sometimes make a large difference. During the hottest times of the summer I don't even bother with my good teas and just make iced tea instead (with something that has more flavor than aroma). Anything with a delicate aroma just doesn't come out. This is pronounced for me when I brew something in my kitchen on these days and then walk back to my air-conditioned [home] office (I use in-window AC, in the office and living room only) - I'll smell nothing but the very slight veggie-protein aroma in the kitchen, but then as soon as I walk into the air-conditioned room I can smell the whole range. I've also noticed that some teas seem to do much better in brewing vessels that breathe, rather than something like a porcelain pot or gaiwan with a water seal (or vice versa). I think some teas need a certain amount of evaporation during steeping to bring out the aroma, which would be reduced on hot and/or humid days. So in other words I don't think heat and humidity can be ruled out entirely, but they don't seem to be the only cause either.

One other thing that I suspect may change is water quality. I use filtered tap water, so it's very possible that they do something different with the water at certain times every year - such as adding some chemical to fight off various organisms that may hatch at certain times. I don't think that this accounts for everything, as some of these people (like Lisa) use bottled water, but I think it may be one factor. I am thinking about finding a decent bottled water to keep around for these times to test it out. I'm also heavily considering a 4 or 5 stage filter pitcher that does a much better job than a Britta, but more importantly only needs filters replaced once or twice a year, which would probably make up for any differences in water treatment.

I also need to get a master test kit for my aquarium soon, and so I'm thinking about keeping a log of the changes to the tap water. While this may seem a little anal, I am really supposed to be doing frequent tests of the tap water for my aquarium anyway (so I can be sure of which readings are due to my care and which aren't, such as nitrates in the water, hardness, pH, and so on), so it would just be a matter of writing them down. Then I could test again on these days to see if there's any difference. Nitrates could very well be a factor.

I've also been wanting to get one of those weather stations (thermometer that also shows inside and outside temp, RH, barometric pressure, etc.) for other reasons, and soon, so perhaps that will shed some light.

A response to the question from Stephane: