I've had a couple of brews recently that won't seem to go below 1.013 . I use safale 04 yeast fermenting in a water bath at 19c. I left the last one for 3 weeks in the fermenter.
The finished beer tastes fine but obviously the abv is ending up a little lower. I also no chill, would that make a difference.? I only do English ales out of Mr Wheelers book around 4%. I also always rehydrate the yeast before use.
Any ideas?
1.013
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IronBlue
Re: 1.013
What is your mash temp?
(Ignoring the decimal - focus on last 2 digits) If you get say 75% (apparent) attenuation from S04 at 66C mash, it means it will attenuate from 1052 to 1013 at 66C mash. (It has lost 39 gravity points which is 75% of the 52 OG)
If you make a 1040 OG beer in exactly the same way with S04 it should finish at 1010, as it has lost 30 points or 75% of 1040....
If your 4% beer started at 1040 and ended at 1013 it will have an attenuation of 67.5% for whatever your mash temp was, that's quite low for S04 if it was 66C - are you mashing on the 'warm side' of 66...?
There will be some minor variations due to grain bill, pitching quantities and yeast health, but that is the essence of it. If you mash warmer you will get less attenuation, if you mash colder you will get more. But it will always be a % of your OG.... Each yeast will have an attenuation %, and by recording your OG and FG and mash temp (the way you measure it) you can start to build up an idea of what is going on....
(Ignoring the decimal - focus on last 2 digits) If you get say 75% (apparent) attenuation from S04 at 66C mash, it means it will attenuate from 1052 to 1013 at 66C mash. (It has lost 39 gravity points which is 75% of the 52 OG)
If you make a 1040 OG beer in exactly the same way with S04 it should finish at 1010, as it has lost 30 points or 75% of 1040....
If your 4% beer started at 1040 and ended at 1013 it will have an attenuation of 67.5% for whatever your mash temp was, that's quite low for S04 if it was 66C - are you mashing on the 'warm side' of 66...?
There will be some minor variations due to grain bill, pitching quantities and yeast health, but that is the essence of it. If you mash warmer you will get less attenuation, if you mash colder you will get more. But it will always be a % of your OG.... Each yeast will have an attenuation %, and by recording your OG and FG and mash temp (the way you measure it) you can start to build up an idea of what is going on....