My main quibble is that I think people overemphasize exact temperatures, and underestimate personal taste preferences, experimentation, and the process of learning. I also think, at least compared to what I like, which is likely not what you like, is that I have found people tend to chronically under-estimate optimal brewing temperatures. On average, I like steeping it hot, although there's one exception that I'll mention below.
Yes, I have used a beverage thermometer to check my temperatures. But you do not need one if you just want to drink tea or brew it for others! The only reason that I bought (and use) this thermometer is so that I can get an objective read on temperature for sharing with others when I write reviews or post on this blog on on other sites.
Some Observations I've Made about Brewing Temperature:
Figures are given in Fahrenheit; a useful tool in case you're curious may be this Fahrenheit to Celsius Converter.
- The temperature of the vessel you're pouring into is important in determining the brewing temperature: if you don't warm it up ahead of time, the water will immediately cool down as it enters the vessel.
- Looking at the bubbles forming on the bottom of the pot or kettle can be a reliable way to assess temperature, but only after you've gotten to know each pot. I have two similar-looking Revereware pots, and one of them forms bubbles at a lower temperature than the other; I don't have a good understanding of why. This caused me to brew some green teas with water that was too hot, the first few times I used this pot to heat water. The bubble formation also depends on how I'm heating the pot--I had to relearn the bubbles as I moved and went from a gas to electric stove.
- I find that people tend to underestimate the temperatures required for brewing tea properly, at least, according to my own tastes. I find that this is particularly true of white tea, which I tend to find less sensitive to high temperatures than green tea, but also true of green and oolong tea, and some Darjeeling black tea.
- Green teas I find to be most sensitive to brewing temperatures, and, along with Darjeeling oolongs, the only teas that will ever be outright unpleasant if brewed with water that is too hot. But even then, there are some green teas that are drinkable when brewed with boiling water. One thing that I have read about that I have found rings true in my own experience is that Gyokuro demands lower-temperature water than other green tea. But I find that even with green teas, people's estimates for optimal temperatures seem to be on the low side. I think 160F for a typical green tea is too low, unless you want a very mild cup. 180F is the target I shoot for, but 160 for Gyokuro.
- A lot of oolongs don't taste good to me unless you brew them with boiling or near-boiling water. A lot of sites recommend 190 or a range of 190-200. I think 190 is too low. This has even been true for me of many greener oolongs. Most oolongs, when I brew them at 190, strike me as bland. An exception are Darjeeling oolongs, which I find typically demand a lower temperature, often to the point of being unpleasant or even undrinkable if they're brewed with boiling water. With a Darjeeling oolong I aim for 160-180F for starters.
What happens when the temperature is "wrong" or "off"?
This varies hugely based on both the type of tea and the individual tea. Trends I've noticed:
- Pan-fired green teas often become extremely harsh: bitter, sour, and astringent, if brewed with water that is too hot. The most sensitive teas in this arena have been the ones with a smoky aroma (strong or slight), such as chun mee or gunpowder. Of all the things that can go wrong based on brewing temperature, this one is the worst, as it often renders the cup undrinkable to me.
- Steamed green teas often look different if brewed with water that is too hot. They often obtain an unpleasant "overcooked vegetable" aroma. In my opinion, compared to the pan-fired teas, they are more drinkable when they go wrong in this manner, but some can still be unpleasant or undrinkable.
- Darjeeling oolongs become both harsh and obtain the overcooked vegetable aroma if brewed with water that is too hot. These teas can become highly undrinkable.
- Black and oolong tea brewed with water that is too cool often seems very bland and with a weak, flat aroma. However, it's never undrinkable, just bland.
- Some white tea can obtain the "overcooked vegetable" aroma if brewed with water that is too hot, but some can also be too bland if brewed with water that is too cool.
- A few teas, including green, white, and some oolongs, lose some complexity to their aroma when the water is too hot, even if they do not acquire any unpleasant characteristics. I find that the teas for which this is the case are a tiny minority of the teas that are out there. More often, though, complexity is lost if the water is too cool--the reason to avoid hot water usually is that it results in unpleasant characteristics into the aroma or flavor that you would rather avoid.
What do you think? What are your experiences with brewing temperature? How do they agree with, or deviate from, the mainstream advice you find floating around out there?