High FG in primary fermentation

Question

I am doing a Diabolo beer from this kit

First, my OG was 1.070 (vs 1.075 recommended).

Now, after 9 days (they recommend 10 days in primary fermentation), the FG is 1.018. The recommend value is 1.010. I will not do the secondary fermentation, and currently I don't see any activity in airlock. After the read of the FG I decide to wait some more days to bottle. However, the temperature in the start of fermentation is 25ºC and now only 16ºC (A sudden drop in temperature in my area). I don't have any way to control the temperature.

The only idea I had was to roll a blanket to the fermenter to raise a little the temperature. This makes any sense?

My question is, if the FG remains around 1.018 can I bottle anyway? Or can be dangerous when priming (explode bottle)? What should I do to low the FG?

Answer 1

"Wait a bit longer, prime and bottle anyway" - is my minimal advice. Leave for some months to condition the beer in the bottle

I personally would try racking off the brew into a secondary fermentation vessel and leave for some more days. 10 days is not long in fermentation terms. I always leave my beers to ferment for 14 days and often bottle at 21 days or more. So there is nothing abnormal in what you see. Starting at 25ºC and now fermenting at 16ºC is OK. I would consider 25 too warm for long term fermentation but the first few days might produce a richer flavoured ale. 16ºC is not a bad temperature for standing/final fermentation and clearing.

I would suppose that after some longer conditioning this beer will be fine. Good luck.

Answer 2

It kinda depends. You have to know a little about your yeast.

Fermentation achieved 74% apparent attenuation, which is about average for most yeasts. Is yours capable of more?

The ABV of your beer is about 7.5%, which might be on the medium-high side. What's the alcohol tolerance of your yeast?

Judging by the beer stats alone you are probably okay to proceed with bottling. The beer might pick up a little extra CO2 over time.