hist-brewing: ancient methods

pwp at cs.cmu.edu pwp at cs.cmu.edu
Tue Apr 14 12:46:29 PDT 1998

< On Tue, 14 Apr 1998, Mark and Eylat Poliner wrote:
< > Does anybody know how medieval brewers estimated temperatures without
< > any measurment devices?

To which bjm10 at cornell.edu replies:

< The first does not require a great deal of fire control.  Bring your 
< water to a boil and let it sit.  The moment that the steam no longer 
< completely obscures your reflection, it is cool enough to add the 
< grist--but add the grist quickly, with much stirring, so it will cool the 
< water properly to mashing temperature as it comes in.
< The second method requires better fire control.  Heat the water until the 
< steam completely obscures your reflection, and NO MORE HEATING.  Add the 
< grist.

Well, I don't do it often, though I have tried it a couple of times.

I've been taking a somewhat different approach, based on an
observation (on building good heat-sinks for audio amplifiers) by
Nelson Pass:

   Anyway, here we are with 330W to dissipate in our heatsinks, and we
   have made it a rule of thumb not to exceed 55 [deg] C on a
   heatsink. Human skin has the remarkable characteristic that we think
   40 [deg] is comfortable, 45 [deg] is hot,

   50 [deg] is very hot, and 55 [deg] is untouchable. This expanded
   temperature sensitivity has a lot to do with injury prevention, and is
   also very convenient for judging whether or not heatsinking is
   adequate. If you can't touch it, it's too hot.


So first off, I've found that, using a 10 G. Gott cooler, and mashing
at a bit over 1 qt. per pound of grain (US measures), 165 deg. F
of water _in_the_Gott_ is too cool to get a decent strike.  So I
usually try to start at 170.

Now that said, if I start with about 85% boiling and 15% cold tap
water, both poured into the Gott and stirred to mix, and then add the
grain.  Then add half quarts of boiling water until it both "looks
right" and is _just_ too hot to stick my fingers into the top inch of
mash, it is about right in the body of the mash.

Of course, this involves a certain willingness to burn one's

On the other hand, if you aren't interested in burning your fingers,
and aren't totally wedded to making English-style beer, one can
_easily_ do a double decoction method mash with only your hand as a
thermometer.  For this, start with the water just above good hot-tub
temperature (the hottest that is comfortable to swirl your hand around
in for long periods of time).  Now dough in (stiff), and add enough
boiling water to raise the mash temp to the hottest level of

For the first decoction, take out 40% by volume of mostly grain, and
_slowly_ raise it to a boil, etc.  For the second decoction, take out
30%.  I've found this technique to be close enough to "spot-on" that I
don't actually need the thermometer at all.

		--Paul Placeway

To unsubscribe from this list, send email to majordomo at pbm.com containing
the words "unsubscribe hist-brewing". To contact a human about problems, send
mail to owner-hist-brewing at pbm.com

More information about the hist-brewing mailing list