Was fooling around with a Boston Lager clone last week. After fermentation slowed I cold crashed for a couple days. The fermentation was slower than usual so I decided to bring the temp back up to 60 deg or so to see if fermentation would start again…it did. I let it go for a couple more then cold crashed again. I am sipping on one right and it is very good and remarkably crisp. Diacetyl rest might not be the right terminology for an ale, but the beer is very good, clear too. Anybody try this before?
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Yeah I try and raise the temp at the end of fermentation for all my beers. Diacetyl rest is the right Terminology ales produce diacetyl also.
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I’ve only done the “rest” twice, once on a lager and on this ale. What the correct procedure? Typically use US-05 and ferment around 65 deg. and use O2 before pitching. Thanks for your help. The flavor and mouth-feel of this batch is awesome!
Typically a d rest is performed after 2/3 of fermentation has been completed. This means doing math and taking gravity readings.
For example, if you had a beer that was 1.050, with an anticipated FG of 1.010 2/3 would be approximately 26 gravity points. So, when the beer hit 1.024, you would want to start the rest.
Gravity readings with a hydrometer equals wasted beer. Gravity readings with a refractometer post fermentation means adjusting for the presence of alcohol.
This is more ideal for Lager than ales. All yeast produce diacetyl, some more than others. More so, some styles benefit from some diacetyl.
To keep it easy, low to mid OG beers (up to 1.050) you could start ramping temps after 3-4 days of ACTIVE fermentation. For 1.051-1.090 start after 4-5 days. 1.090+ wait at least 6 days. Of course, the cooler the fermentation the longer you would wait. So for ales in the low 60° maybe add a day. For lagers add a couple days.
These are my general guidelines. Feel free to take your measurements but these seem to work best for me without wasted beer. And doing math.
