2.5 gallon batches = faster fermentation?

[jgaepi]

Curious as my 2.5 gallon batch has slowed down considerably after day 2, do 2.5 gallon batches have a faster fermentation period? With less liquid and overall volume, does this speed up fermentation? Thanks.

 

[CoreyD]

I do 2.5 gallon batches exclusively, and always leave it for at least 2 weeks. I have had a 1 gallon that wasn't done after 2 weeks. And that was with no temperature control, around 70 with US-05. I don't think batch size has anything to do with fermentation time.

 

[IslandLizard]

Fermentation can slow down due to many factors, only a gravity reading can shine light on how far it is done. Beer can be done actively fermenting after 2-3 days, but there is a period of conditioning afterward that is just as important for many beers to come into their own, only few exceptions noted. Batch size has little to do with that, but yeast pitch and vitality does.

I've had certain beers gone from grain to glass in as soon as 5 days, including a 3-4 day dry hop and be perfect (NEIPAs). But that's more an exception than rule. Allowing a week after active fermentation comes to an end for yeast to clean up (condition) and clear (flocculate out) is common, but many beers benefit from a longer time, some as long as months or even years.

 

[S-Met]

Possibly, but more likely the reason is a greater pitch rate. The yeast:wort ratio is greater in a 2.5gal vs a 5 gal unless you are carefully calculating your pitch.

 

[jgaepi]

I pitch a whole dry yeast pack into the 2.5g. Makes up for lack of growing out my yeast. Fermentation is still happening, albeit much slower now, but I was just wondering if overall period could be quicker.

 

[dmtaylor]

I've been brewing small batches for many years. They take just as long to ferment out as bigger batches. No perceptible difference.