You may have read that we like to play with water. Lacking an agenda for the weekly tea seminar, I bought a bottle of Gerolsteiner, the sparkling water with a hefty 2527 total dissolved solids, and resolved to brew tea with it. I heard they were doing this in the next Jackass movie.
I was a little worried about boiling sparkling water. The internet reassured us that the water would simply lose its carbonation, which was desirable in our case. If you lean over the kettle while it’s boiling carbonated water, do you inhale carbon dioxide and pass out?
So yeah, it was god-awful. We tried boiled Gerolsteiner with a heavy-roasted Ali San and a Nan Nuo pu-erh. Our throats positively constricted and our stomachs hurt. Looking in the kettle, we were treated to the sight of precipitated minerals. The evening wrapped up pretty quickly.
Thankfully we had tried some other things first. I discovered a spring water bottled in Jeju island, Korea, a region noted for its tea. You should definitely check out the water’s website if only for the preposterous bar graph purporting to prove Jeju water as the wellspring of longevity. I couldn’t find the complete chemical analysis on the website, but hey, it’s on the bottle!
We used the Jeju water to brew Tea Gallery’s Tenryu Sencha. Brandon comes from a tradition of brewing sencha with relatively cool water, to maximize the umami. I prefer more of a leafy taste than a soupy, and I always press him to brew it hotter. We talked about my hypothesis about brewing parameters: namely, that hotter water brings out astringency-causing catechins, and cooler water emphasizes mouthfeel-contributing amino acids. Brandon made an apt analogy, realized in clip-art form, to the “triangle of photo exposure”: there are multiple variables influencing the final product, and increasing one of them can be approximated by scaling back the other two. Behold:
I tend to think of the tea variables as tripartite also: water temperature, leaf ratio, and infusion time. I don’t see minerality–minerals added to the process by water or vessel–having a dynamic effect on other variables in the infusion process. Rather, they’re an extra later that influences the resultant taste. But I could be wrong; perhaps certain minerals can inhibit the solubility of tea’s component chemicals. This would be more plausible at extremes, at concentrations of minerals high enough to be disgusting and toxic.
Also, brewing vessel is too complex a variable. This could include subtractive effects due to the vessel’s porosity, additive effects from the vessel’s material makeup and residue from brewing history over time, and heat loss profile. But let me not to the marriage of true minds admit impediments. Thanks, buddy.