Beersitting Instructions

[Clinton Ebadi]

Greetings,

These are directed toward Steve, but perhaps may serve as a general
guide to watching over our friends the yeast who turn our hard work
mashing and brewing into beer.

One nice property of five or six gallons of liquid is that it contains a
lot of thermal mass and therefore inertia. As such, unless you have OCD
(I might) about such things, the influence on internal temperature from
the external environment must only be adjusted once or twice a
day. Within this there is an implied curse that you can only exert force
upon the temperature in multi-hour movements.

In the case of Nowruz, primary fermentation is in full effect presently
and will probably continue until late tomorrow afternoon at full
tilt. This produces a lot of heat, and so the water tray must be filled
all the way and the fan set all full speed due to the unfortunate
reality that the ambient temperature upstairs during the day time is at
best 76F as well.

As such when I depart in the morning the fan will be at full speed and
the fermenter hopefully around 64F (the evening cools the air and so by
leaving the fan at full power overnight I can drop the temp by 3-4F).

This gives a temperature margin of +/- 4F before either undesirable
flavors are produced or the yeast fall asleep and sink out of solution.

In the evening one of two situations will exist:

 a. (Probably) primary fermentation will be on the downswing. Airlock
    activity will be around 1/(2s). In this case, the fan should be
    turned down to 1/3 since the yeast will produce less heat and so
    overcooling is risked. Luckily, lower yeast activity implies the
    ester/phenol production phase has ended and so overshooting
    temperature is not really a problem.

 b. Primary fermentation will be at near peak levels (possible, primary
    can last anywhere from 24h-72h and I've tended S-05 only once
    before). In that case, 2/3 is probably a good idea to maintain the
    temperature.

Saturday, in the case (a) is true the fan will probably just need to be
cut off and some water added. In the case of (b) ... we'll see...

In any case, Steve, when you check in on the beer give me a call and
I'll tell you what to do based on the observed beer conditions. I'll sms
you before I leave with instructions on how to enter the house without
terrifying my Grandmother and being savagely attacked by a sheltie.


-- 
Ethan: i'm working on myself
Ethan: the self is the most important thing
Ethan: i learned this from a packet of tea
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