We seem to spend a lot of time and effort chasing brew water of a perfectly stable temperature. I’ve seen people demonstrate to me at great lengths that their machine is fantastically stable. This is all well and good – it gives us consistency in the cup, removes a variable from the process but in all this it leaves one question unanswered:
Does one brew temperature satisfy every coffee? More and more places are interested in varying their coffees – be it week to week or even day to day. Single origin shots in particular seem to be taking off in a big way.
In my experience it would make sense for different coffees to have different perfect brew temperatures. Temperatures function is to liberate the solubles created in roasting and bring them to the cup. Control over temperature gives us selectivity.
For me its a part of blending – having chosen the coffees, roasted them and blended them I then taste the blend through a variety of temperatures. The joys of a digitally controlled boiler! Just one degree centrigrade can right the balance of a lopsided single shot, or expose the real sweetness of blend. It never fails to amaze me how often this is ignored.