Krausen Dropped Too Early?

[bevdawg]

Hi all!

Quick question...

Made a clone of Sam Smith's Oatmeal Stout. Has all been going very well and early tastes are spot on!

I used Wyeast 1084 Irish Ale, which I had made into a 2ltr starter about 36 hours before hand. Anyway, had a nice krausen on it (pitched on Monday evening) and now, Wednesday evening it's dropped. It's been at 20c the whole time. It looks maybe 75% fallen. Started at 1.051 OG and now it's at 1.024... aiming for 1.012/13...

Has anyone used this yeast before? Can I expect any more from it? Should I shake it up or ramp the temp up a few degrees?

Cheers

 

[beerbog]

Let it run, I've had some drop out early and they are just fine. :beerbang:

 

[dougsbrew]

keep your eye on the gravity readings, as long as its still dropping it should be fine.

 

[manticle]

Long time since I used 1084 but from memory, it's in keeping with most UK yeasts of my experience. Almost every one gets to somewhere between 1030 and 1020 and slows/stops.

Normal rousing tricks get them into line. I wouldn't rely on krausen though - sometimes it fails to drop despite hitting FG and sometimes it drops early while beer keeps fermenting.

 

[dr K]

As you know Sam Smith uses a traditional yorkshire square and the yeast used has over many many generations developed its own unique character which is passed on to the beer. This yeast is (by accounts) very active but also very much a topper, so depite its activity rousing (in the home brew situation unless you want to build a yorkshire square) is required.
With 1084, unless you are sadly lacking in nutrients, have under pitched or use old yeast without a starter you should have no problems, its a bonza yeast, has good fermentation over a wide temp range, usable flocculation, high alc tolerance and of course decent attenuation (70% or more?)
See what happens, if the beer is under-attenuated pay some extra attention to yeast health/conditions next time. If its great, well..drink up.
K

 

[donmateo]

Using 1084 right now in a baltic porter (OG: 1.094), yesterday at last check it was at 1.046 (after 3 days, temp around 16 degC), and right now it looks like it's still going strong. It's amazing the difference pitching rate makes though - this one is on it's third round being reused from two previous porters, so I had a good amount, and it really got off to a good start.
But I think it's better to be proactive and stir it up a bit if it looks like it's puffing out, esp on the home stretch. Still though - in the past at times I've found it pretty tricky to get the FG below 1.020.
Also have had those where krausen dissapears mysteriously, and looks like it's not going - but a closer peek through the glad wrap shows it's still bubbling away.

 

[bevdawg]

Thanks all. Just checked it again, around 20hrs later and it looks like it's around 22, so still moving a little. Fingers crossed it keeps dropping.

What's the best way to encourage?

 

[super_simian]

Warmth (slight increase) and/or agitation (swirling, stirring, racking etc...)

 

[bevdawg]

So it's now almost sitting at 1.018, and it's been 9 days. Don't expect I'll hit 12/13. Just wondering why this has happened. It was the first brew I aerated with a whisk over aquarium pump. Could it have been from lack of oxygen?

 

[dougsbrew]

So it's now almost sitting at 1.018, and it's been 9 days. Don't expect I'll hit 12/13. Just wondering why this has happened. It was the first brew I aerated with a whisk over aquarium pump. Could it have been from lack of oxygen?

show us your whisk..
did you airate the whole lot or just the top surface - whisks are generally small.
big mixing spoon stirred vigorously works well for me.

 

[MHB]

Irish Ale is a pretty solid performer, given that it got off to a good start I would suspect that the wort may be less fermentable than you expect (might want to look at your mash temperatures), another possibility is that the temperature is varying more than you realise. Not knowing what sort of temp control you are using, but if the temp is dropping at night then warming through the day, that might be upsetting your yeast You could take a small sample and warm it to about 25^oC and hold it there for a couple of days and see where it finishes.

MHB

 

[Jazzafish]

So it's now almost sitting at 1.018, and it's been 9 days. Don't expect I'll hit 12/13. Just wondering why this has happened. It was the first brew I aerated with a whisk over aquarium pump. Could it have been from lack of oxygen?

It is a possibility, especially with a 3rd generation yeast. I have noticed most issues related to oxygen amplify down the generations, by this I mean may fall short 1 or 2 fg points in the first brew and then yeast will start to get lazy and hazy as it goes down the line. As you said it started great, this may not be an issue for you.

Is it possible you have over-pitched? This can cause an under attenuation.
Another consideration is mash temp, if it got a little warmer than normal it can have an affect.
Lastly, I find English yeasts rush to flocculate even after a few degrees temp swing.

Either way, if it was my brew I'd sanitise a long spoon and gently break up the yeast cake by lifting it back in suspension. Giving the beer a little stir too but trying to avoid aeration at this stage. I'd also ramp up the temp to 23*C, keep in mind esters are formed in the yeast growth stage. Personally I get better attenuation when I ramp up the temperatures after high krausen by 2 to 4 degrees without the risk of esters (Allow a free rise over the krausen formation if you want extra esters).

I'd also recommend you try another brew using the same yeast in its next generation and let us know how it ferments. Use the mr malty pitching rate calculator and follow your normal aeration and nutrient procedures. If you notice the brew ferments well, then you can assume there was a temperature issue in mashing, pitching rate or ferment control for this particular brew. If the problems amplify, dusty yeast that drops early; assume that the yeast is not what it used to be and look into your yeast harvesting/selection techniques or aeration/nutrient/pitching rates.

Look forward to reading what you find

 

[Phoney]

I've got a "Better Red than Dead" with 1084 on at the moment. After 7 days the krausen disappeared completely and it only dropped from 1.052 to 1022. Now it's been 13 days and it's gone down to the FG of 1.14. Will be bottling tonight. :beerbang:

 

[Jazzafish]

nice post MHB...

 

[bevdawg]

Great info guys, thanks to you all.

OK so I use a elec temp controller, set at 20 connected to a heat pad in my 'office'. Some morning, after those recent cold as crap nights I've gotten up and it's been on 19, so I think the only temp variable the whole time would be 19-20. I now have a blanket over the top of it all to try and keep the temp on 20. Might crank it up a few degrees today?

My whisk is small, but it's not the size that matters... no hang on, it is in this case! I prob only aerated the top half of the wort now I think about it, sign. Big spoon is going to be used next time perhaps.

Yeast was first gen, I was more worried about too little than too much...

I was going to let it ride out to 14 days and see what happens, but maybe I'll try and stir the bugger up! My last brew had an infection, so was trying to avoid opening this baby up as I really do not want another, but maybe it will be worth it.

Phoneyhuh you give me hope yet!!!

 

[bevdawg]

So I just did another hydro reading and it's dropped another point since yesterday, just... so I guess it's still chugging along, just not at speed