Anyone have results from stirring up yeast cake?

[McGlothan]

Hi,

I have an IPA I made a little over 2 weeks ago. OG was 1.084. Fermentation took off like a rocket and had vigorous fermentation for about 1 1/2 weeks. After it slowed, I checked gravity at exactly 2 weeks and it was 1.022. This is slightly higher than what I was expecting from the recipe. Now against all advisement against it, I took the mash paddle handle and stirred up the yeast bed (GENTLY) to rouse the yeast into suspension again. Today it looks as if there is slight activity again. I know about negative effects from oxygenating fermented wort and I know someone will respond advising against it. I have also read many threads about it but can't seem to find results from anyone who has tried this before. Im also aware my beer might not have been finished but all signs were pointing to fermentation being complete. So in short, Has anyone had results good or bad from trying this?

Thanks,

Shawn

 

[BigFloyd]

Assuming that your mash paddle handle isn't made of wood (which is pretty much impossible to sanitize), I don't think you did anything harmful since you were careful to not splash it around. I've done it and coaxed another 2 points from a coffee porter recently. Before the gentle stir, did you raise the temp up to about 70-72*F?

You do realize that, considering your high OG, getting to 1.022 was about 74% attenuation, right? Depending on the strain you were using and your mash temp, that may be a reasonable FG.

 

[Chadwick]

I've had great luck shaving points off the gravity by rousing the yeasts. I have also found that doing that a couple of times along with allowing 4-5 weeks in the primary can get the FG down some more.

Since this is an IPA, you have the benefit of really laying the dry hops to it as well. This will cut back on perceived sweetness quite a bit. I expect you will have a very nice IPA in the end. You just need to wait it out and let it do its thing.

 

[ArkotRamathorn]

Besides making sure it was sanitized and you didn't play Marco Polo in the beer with your mash paddle it should be all good. Had a 1.095 BDSA, checked it after a week and it was at 1.025, I knew if I left it another week in primary it'd probably drop a lot more, but I gave it a gentle stir with a long plastic sanitized spoon. No noticeable off tastes a week later on the hydrometer sample that read 1.012 (I made sure I checked what temp my hydrometer reads 1.000 at so I'm reasonably close to sure it was an accurate reading).

I'm pretty sure there are some commercial breweries that rouse their yeast, Samuel Smith's comes to mind with their huge open fermenters.

 

[mikeoholic]

I've dropped an English ale by .005 with a gentle rousing. I've only had to do it once but it worked.

 

[beersk]

1.084 to 1.022 isn't bad. Depending on your yeast - you're still at 8.1% abv with about 74% attenuation. I roused Wy1469 recently on an IPA that started at 1.065 and stopped at 1.022 and it came down to about 1.018. That yeast needs to be 64F and warmer. But I can't get beers much over about 62F right now since my house is pretty cool, so it makes sense that it finished higher like that.

 

[McGlothan]

Thanks for all the feedback everyone! I planned on letting this sit in primary for a month and I bet it would have continued to drop slowly but I couldn't imagine it getting much lower without a little wake up call. Already today, which has now been 3 days since I roused the yeast, it appears to be settling out again. I am betting I would see a lower FG if I checked now, but I've dipped a little too much into the carboy for my own comfort as it is. I will check it at an exact month (which is about 1 1/2 weeks from now), an post my results. Thanks again!

 

[McGlothan]

Assuming that your mash paddle handle isn't made of wood (which is pretty much impossible to sanitize), I don't think you did anything harmful since you were careful to not splash it around. I've done it and coaxed another 2 points from a coffee porter recently. Before the gentle stir, did you raise the temp up to about 70-72*F?

You do realize that, considering your high OG, getting to 1.022 was about 74% attenuation, right? Depending on the strain you were using and your mash temp, that may be a reasonable FG.

Yeah I realize it's not bad but I used WLP090 (Super San Diego Yeast), which Ive heard is a monster and pitched an adequate starter. I also used 1 lb of dextrose in the boil to achieve this OG. I am just really trying to dry this one out.

 

[gwapogorilla]

I do it all of the time...with a wire clothes hanger. I cut it, put a small 3" bend at one end, wash and sanitize it. Stick it through the "bung hole" and spin that 3" section to stir my wort. No splashing, no oxygen getting into the carboy....works great.

 

[McGlothan]

I do it all of the time...with a wire clothes hanger. I cut it, put a small 3" bend at one end, wash and sanitize it. Stick it through the "bung hole" and spin that 3" section to stir my wort. No splashing, no oxygen getting into the carboy....works great.

Great idea! I will try it next time

 

[pjj2ba]

Why not just leave it closed and just swirl the fermenter a little bit? That's what I do. This way you guarantee that no new O2 gets in.

 

[BigFloyd]

Why not just leave it closed and just swirl the fermenter a little bit? That's what I do. This way you guarantee that no new O2 gets in.

That works well for many yeast strains. There are, however, certain ones (like 1968ESB/WLP002) that form a very firm cake when they drop out. You're not going to get those up by swirling the fermenter.

Also, if a person has been popping the lid off the bucket and disturbing the CO2 fog atop the beer, very gentle stirring may actually present less of a risk of oxidation than would swirling/shaking.