How I use ISO standardized sessions to make better tea

ISO, thoughts

I drink every tea reviewed here on Form Follows Tea the same way,* following this iso standard (yes, it is a real thing) with a few of my own specifications (e.g. pre-warming the pot, using a specific type of water. Full details here.) I use a tasting set (the less sexy cousin of the teapot), very hot water (98C), and a lengthy steeping time (6 minutes).

I’ll be the first to tell you that drinking tea like this is usually not ideal. Everything comes into the cup at once, and for a lot of teas this means too bitter, too unbalanced, too astringent for typical drinking. I’m pretty used to it by now, but if I’m just sitting down for a relaxing cup of tea, this is not what I do.

So why do it? Why torture myself with bitter tea and unglamorous vessels? Well, half of the answer’s in the title – to make better tea.

This sheng puer leaf from the Bulang region sure is sassy.

Simply put, steeping the crap out of a tea shows me its limitations. Knowing the limitations of an individual tea gives me a starting point from which I can trace back my steps and arrive at a steeping method that highlights the good and de-emphasizes the bad.

This part takes some experience but it isn’t rocket science: too much bitterness? Try high temperatures, flash steeps, and a low tea:water ratio. Excellent high notes, but a thin body? Use a ceramic or glass brewing vessel to retain the high notes, but use water with a higher TDS to fill out the body. Again, it just takes some experience to gain an intuition about the ideal steeping method for a given tea, but these are things I never would have learned if I had been afraid of “ruining” some tea by pushing it too hard.

And frankly, if you’re paying for good tea, you’re not getting your money’s worth if you treat it with a delicate hand. Oftentimes I’ve found the most exciting element of a tea lies at the very edge. You’ll never reach the edge if you always steep at 85C for short steeps. (That, and it’s sort of an open secret that the better grades of tea won’t get bitter when steeped hard.**)


 The second reason for steeping tea following a standard procedure is the more obvious one – to establish a repeatable benchmark by which I can test all teas evenly. This is done because, like a lot of curious humans, I have a strong desire to know what is Good. If all my tests are run in the same way, I find it a lot easier to convince myself that I am capable of judging this. Whether it matters is another matter entirely.

*due to the form of some teas (matcha is an obvious one, but also large unbreakable tea balls), there are some cases where the standard can’t be applied.

**Depends on the type of tea to a certain extent, but the most obvious (and perhaps, surprising) case is green tea. I’ve even drank gyokuro and sencha (both Japanese styles of broken leaf green tea) steeped in ISO fashion with no bitterness.

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