Stalled Fermentation

Australia & New Zealand Homebrewing Forum

Help Support Australia & New Zealand Homebrewing Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

shimple

Well-Known Member
Joined
17/8/08
Messages
99
Reaction score
0
My Porter startedat 1.051, fermented using US05 for 6 days at 18'c and then stopped. Gravity is currently 1.021.

So i gaveit a shake and bumped it up to 23'c andwaited 2 days. Still 1.021.

Should i throw in another pack of US05?
 
Mash temp? expected final gravity?

More details on the recipe?

Cheer SJ
 
expected final 1016.

Mash temp - 68'C

Reciepe:

Pale Malt 62%
Flaked Barley 10%
Flaked Oats 10%
Crystal 140 6%
Chocolate 6%
Munich 6%
 
You say the current gravity is 1021. How many days has it been at 1021?
 
Hi Shimple,
68c is the higher end of the mash temps to produce fermentables (tends to produce flavoursome malty deliciousness rather than thinner dextrinous sugars that are easy on the yeast -I don't know anything more technical than that). I did a basic pale ale on the weekend mashed at 64c... this one fermented out from 1.044 - 1.009 using US-05 at 18c in 4 days (I am leaving it to relax before racking). I was blown away as this is the first time I have mashed so low (and am now more familiar with my setup).

The two brews before that were mashed at 68c and 69/70c respectively (while trying to get to know my set up a bit more intimately - I was aiming for 65c and 67c), and they both only dropped about 25 - 30 gravity points each. I tried the "fast ferment" idea by drawing some off into a grolsch stubby etc but there was nothing left to ferment out...I added a teaspoon of malt out of interest and this caused a good solid ferment within 5 hours so my yeast was fine, but I am positive that due to my higher mash temp the yeast had done all it could with the fermentable material that the mash had produced.

Of course I am inexperienced at all this, but this is one possibility to conisder...(you could try drawing off a small amount like I did to do a mini experimental ferment and that will maybe give you your answer).

Regardless, good luck with it all!
 
I was having the same probs as Lecterfan, my brews kept coming up a few OG points short, and tasted quite sweet.
You could consider getting some enzyme to help the yeast out, or pitching some more yeast.
 
Pull out a sample and try some. if it tastes too sweet for you to drink, then you have nothing to lose in adding more yeast. You may want to re-hydrate the yeast then pitch to a 500ml to 1L starter to make sure it is active and able to cope with the alchohol already in the beer.

I had a stout with an OG of 1051 just finish at 1013, with my hopping of 43 IBU it has a nice balance on the dry side. So denpends on how you hopped it, whether it may be cloying..

If that dosn't work, then it is likely fermentability issue with your wort and perhaps the percentage of flaked grains...

Hope this helps.
 

Latest posts

Back
Top