When to stop fermentation ...

[Old_Skool]

So every beer style has suggested FG range -- when I started brewing I would let the wort in primary ferment until it was in the suggested range - then rack to secondary for a week and then bottle. This seemed to work well and I brewed many a balanced and malty good brew.

Then another brewer acted quite surprised that I didn't let the wort sit on the for at least a week or so and let the yeast ferment until they were done.

So for the past few batches I've done that with the difference being that my FG's are consistently down around the lowest ranges of 1.009 or 1.010 where in the past for say a basic amber ale my FG might have been 1.015 when I stopped fermentation on hitting the FG range ----- its now down around 1.009 or 1.010

Any consensus on this ? I know that the lower FGs are going to be higher in alcohol and the beer is supposed to be drier in taste. I prefer my beers balanced (more or less) and malty .... what to do ?

[Stinkfist]

FG's should be adjusted with Mash temps, not sure how racking to a secondary would stop it from continuing to ferment...or do you just not take another reading after you rack? cuz I bet it continues to go down..

[Nyakavt]

FG's should be adjusted with Mash temps, not sure how racking to a secondary would stop it from continuing to ferment...or do you just not take another reading after you rack? cuz I bet it continues to go down..

+1. Most brewers are not going to stop the fermentation prematurely, that would lead to sweetness not maltiness, as well as acetydehyde and diacetyl in some cases and bottle bombs in others. We already have ways to get more body or more malt flavor without the negatives of prematurely ending fermentation. If you want more body, mash at a higher temperature. If you want more maltyness, use a 'maltier' malt (like english pale ale malt instead of 2-row, or munich/melanoidin/aromatic malt).

All that said, wine/mead makers do stop fermentation, but they've got a different product all together that I don't totally understand. Either way I don't think it really works in beer.

[BrianL]

Jamil's advice has worked for me. Ferment until you see no more signs of activity and then wait a couple days. Those are some low finished gravities...maybe you're getting some wild yeast in there?

[Hale Brew]

Those gravities seem normal. It really depends on a combination of factors. Yeast, ferment temp, mash temps, etc. 001 or 1056 can easily get down to 1.010 and regularly do for most of the beers I do with them.

[TheTodd]

FG's should be adjusted with Mash temps, not sure how racking to a secondary would stop it from continuing to ferment...or do you just not take another reading after you rack? cuz I bet it continues to go down..

+1 on adjusting the mash.

Additionally, are you varying your yeast selection? If you always use a California ale yeast, you're almost always going to finish in the 1.006 to 1.010 range. Try a less attenuative English yeast if you want to end up around 1.012 to 1.014. Unless your OG is 1.070 or above, I would think that 1.015 is going to be too sweet. A lower FG doesn't mean you lose maltiness, it just means you gain a drier finish that helps make those malty beers go down easier.

[ajdelange]

Stopping fermentation is one thing. Taking the beer out of the fermenter is another. Just becuase you rack the beer to a keg or fill it into bottles doesn't mean fermentation has stopped. Check the SG on one of the beers you packaged in the days when you took the beer off early. It will probably have continued to ferment.

In lager brewing the beer is taken out of the fermenter when it has 1 - 2 °P left to go. This extract is consumed by the yeast in the lagering tank gradually (months in traditional lagering practice).

If you do manage to halt fermentation (e.g fill into bottles before the yeast are finished and then Pasteurize) you will have done yourself a disservice. The beer will not be as good as it could be.

If you find that your FG's are consistently lower than what the yeast supplier suggests are typical (Example 10 °P wort; normal ADF range 75 - 80 %, FG 1 °P) then something isn't kosher. There is too much raw sugar, the wort isn't dextrinous enough, contamination with a hyper-attenuative strain or bacteria, etc.

[Bokonon]

Checking the hydrometer against distlled water is a good idea also