Stuck Ferment....Pitch more yeast?

Hello All,
I’ve got an extract IPA that has stopped fermenting at 71% attenuation(1.072-1.020). I’ve had a stable gravity reading for a full week now. I know there may be many reasons for why this occurred and at the moment am not trying to get help with figuring out why. I have already tried raising the temp(up to 69 degrees) and gently swirling the yeast back up into the beer and this hasn’t seemed to do the trick. My question is, would repitching another packet of yeast have any effect? I originally used two packets of S-05 and have another one ready to put in but wanted to get some feedback first. Are there any downsides to repitching? If I do it, is there anything I need to do besides rehydrate and pour it into the fermenter? I’ve had batches that stopped at 70-72% attenuation before and really don’t like the extra sweetness that I get. Any tips would be much appreciated!

[quote=“bpinon”]Hello All,
I’ve got an extract IPA that has stopped fermenting at 71% attenuation(1.072-1.020). I’ve had a stable gravity reading for a full week now. I know there may be many reasons for why this occurred and at the moment am not trying to get help with figuring out why. I have already tried raising the temp(up to 69 degrees) and gently swirling the yeast back up into the beer and this hasn’t seemed to do the trick. My question is, would repitching another packet of yeast have any effect? I originally used two packets of S-05 and have another one ready to put in but wanted to get some feedback first. Are there any downsides to repitching? If I do it, is there anything I need to do besides rehydrate and pour it into the fermenter? I’ve had batches that stopped at 70-72% attenuation before and really don’t like the extra sweetness that I get. Any tips would be much appreciated![/quote]

How do you know it’s stuck and not done? If you already pitched 2 packs of 05, I doubt there are any fermentables left.

I’m not sure I would expect this to ferment anymore. 70-75% is very common for that yeast. Any higher usually comes from a very fermentable wort. If drier beer is your wish you should focus more on creating a more fermentable wort (simpler sugars) by substituting some of your malt extract for table sugar. Since you aren’t brewing all-grain this is about the only tool you have to change the fermentability of the wort you produce.

It’s been in primary for 3 weeks now. The recipe included 7lbs LME, 1lb DME, 1lb of dextrose and some grain for steeping. I’m surprised it hasn’t fermented further even with the dextrose. I just started brewing this summer and out of 6 kits, I’ve only had 2 batches get an attenuation that was in the mid-range of what the yeast is expected to get. Over the past few months I’ve spent hours reading forums and John Palmer to see how I can improve and now I hesitate to buy any more extract kits because it’s so hit or miss. I feel like I am doing everything per best practice. Would jumping to all-grain give me some more control and allow for better attenuation?

It absolutely would. Are you set up for doing a full boil? If so, all-grain BIAB really only requires a large mesh bag and a good thermometer.

Yeah this was why I made the jump to all-grain after only 4 batches. I was so annoyed by high FG beers or beers too thin in body cause I added too much sugar.

I did recently get a 10 gallon pot and a burner for full boils. Sounds like I will be looking into BIAB. Unfortunately I have an extract kit on the shelf waiting to be brewed and a crapload of overly sweet beer already in bottles that I’m going to need to work through.