Spring Temp Swings

Northern Brewer General
1

These can be troublesome times around here for my temperature regulating.
I have a fermentation chest freezer on a temp regulator for the hot months. A week or so ago
we were hitting the 80s, so I stuck an IPA (primary) in there at 66 deg and she chugged along for a week or so. Then the bottom dropped out and it was in the 60s with temps falling to the low 40s at night. This fermentation ‘chamber’ is located in the not very insulated tool shed. Obviously it works great when the temps are high, but I know I’m getting some sizable ambient temp swings in there due to the colder weather…which supposedly ends tomorrow.

So the question is, what negative effects can colder temp swings have on beers outside of a stuck fermentation?
In this case never rising above 66, but dipping down in the 50s and back up and back down again over
a week or so…
thanks in advance!

2

ideally you really don’t want it to drop much. If it does, the yeast go to sleep or get lazy (start flocculating). The constant back and forth isn’t ideal for a good clean fermentation - and attenuation could suffer. Plus, I believe that this can result in some unfavorable flavor compounds (diacetyl and so forth).