to pick up quickly on the geometry part of brewer design, it’s been something i’ve been thinking about for a few months now and i’m convinced that what the numbers show in terms of evenness is down to the elongated base of the Melitta style brewer.

I’m convinced that the longer more barrow-like shape of the extraction bed seems to lend itself to a evenness more consistently rather than the cone-sphere (is there a better name for this) shaped bed of the V60 or Chemex.

My initial thoughts are that the shorter transit length through the grinds from top of the bed to the egress has an influence on the extraction, much work still to do though.

Mat

A fine experiment, and I agree: Scott Rao’s book is essential. It has changed my thinking on the elements of brewing, especially with the concept of agitation.

I agree with Rasmus on the kettle thing; it’s much easier preinfusing with it than right from the boiler, I would think.

As I surfed the online tutorials on v60 brewing, I noticed many of them agreed on making that hole in the coffee grounds before preinfusing. Perhaps that leads to a more even extraction—more to the bottom than what came in your result. I couldn’t imagine any other purpose for making that hole…

If I remember correctly, Scott Rao puts quite an emphasis on keeping the volume in the chamber as low as possible while brewing. I can’t reference the book now because I’ve already borrowed it to a friend of mine (never again!). You on the other hand almost fill the chamber (i.e. use the v60 like a Melitta), both in the stirred and unstirred brewing version. Which is not necessarily wrong; as an experiment, where most factors should be under control, these two brewing styles show extremes in both directions.

I think we all have our individual idea of a mixed method of the stirred and the unstirred. Pouring over with the kettle I find more and more akin to espresso making; keeping a slow-but-steady flow requires the same consentration as tamping the coffee evenly on the portafilter.

I hope I make some sense, if any. I just want to say that this experiment is very inspiring. I guess people are still realising the massive influence this experiment will have; and many, I think, have had the same idea, but never carried it out.

Looking forward to seeing new results in the future!

— Tumi