Seperated yeast?

Share your experiences of using brewing yeast.
Post Reply
tourer
Hollow Legs
Posts: 479
Joined: Sun Oct 11, 2009 9:09 pm
Location: spitting distance of the Beacon hotel, home of Ruby red

Seperated yeast?

Post by tourer » Sun Jan 29, 2017 12:06 pm

Greetings all, this has never happened to me before that I have noticed. Using a US05 pack of yeast and monitoring the ferment. After about a week it appeared that it was still fermenting "it wasn't the fermentation was done" the yeast had separated from the wort leaving about half inch floating on the top. I gently stirred it back in as I was about to transfer to a secondary. The next day transferring to the secondary the yeast mixed/dropped into the beer. After transfer I salvaged the slurry for possible future use. Left it in the fridge with the secondary at 1c and the yeast has separated again thick at the top, beer underneath and below that milky yeast. I have used Seymours Citra recipe but using East Kent hops "some of my own home grown for the boil" and LHB for dry hopping. Anyone got any ideas.
Thanks

Chug

Re: Seperated yeast?

Post by Chug » Mon Jan 30, 2017 1:15 am

It sounds like it's still fermenting, you say the fermentation was done, what was the final gravity reading?

User avatar
Kev888
So far gone I'm on the way back again!
Posts: 7701
Joined: Fri Mar 19, 2010 6:22 pm
Location: Derbyshire, UK

Re: Seperated yeast?

Post by Kev888 » Mon Jan 30, 2017 11:46 am

It may still have been going slowly after a week, but sometimes the krausen/foam on top can persist after fermentation too. It will usually sink to the bottom given time, or else you can rack from under it.

Stirring it into the wort wouldn't have been my first choice immediately before racking, partly due to the extra yeast that would be carried through, and partly because there can be undesirable flavours in the foam. But these will usually settle out again so no harm done; if the fermentation had been closed there would be little likelihood of flies/spores etc floating on top.

Rather than yeast, this could also partly consist of other matter - e.g. that made it through from the kettle. Sometimes infections cause unusual deposits to form on top too, so be a little suspicious of your harvested slurry, just in case.
Kev

User avatar
john luc
Lost in an Alcoholic Haze
Posts: 669
Joined: Thu Jul 08, 2010 11:04 pm

Re: Seperated yeast?

Post by john luc » Mon Jan 30, 2017 12:19 pm

I had used US05 for 2 brews,pitched into first one and then reused some of the slurry to pitch again. I also use a conical to collect the yeast and had drawn off the yeast and washed it in sterile water and put it into the fridge. After a few days I took it out and was planning to give some to a friend so cracked open the jar,no CO2 build up in it but after a few minutes the yeast cake split and half rose to the top of the jar. Assumed it was CO2 but never had that happen to me before.
Deos miscendarum discipule
http://www.nationalhomebrewclub.ie

tourer
Hollow Legs
Posts: 479
Joined: Sun Oct 11, 2009 9:09 pm
Location: spitting distance of the Beacon hotel, home of Ruby red

Re: Seperated yeast?

Post by tourer » Mon Jan 30, 2017 11:14 pm

Thanks for the replies, checked it this morning and there's no sign of of floating yeast. As already been suggested it may be matter carried forward and i did suspect that but i wanted others with more knowledge/experience to give an opinion. fingers crossed the beers OK and i wont be making bombs. Another lesson learned. when dry hopping always break up the hops as they will stay in a lump if just chucked in [-X .
thanks again

User avatar
Kev888
So far gone I'm on the way back again!
Posts: 7701
Joined: Fri Mar 19, 2010 6:22 pm
Location: Derbyshire, UK

Re: Seperated yeast?

Post by Kev888 » Mon Jan 30, 2017 11:46 pm

Yes, for loose dry hopping then a slight bit of stirring in can also help to disperse and submerge them - gently so as not to aerate, and of course with a well disinfected stirrer. With whole hops I usually get a mixture of some sinking and others floating when it comes to racking time. Some people dry-hop in a (boiled) and sometimes weighted bag though, so breaking up beforehand is even more important then. Pellets tend to break apart and disperse a little more easily, and I quite like them for this purpose, but not everyone likes them as much.

WRT the yeast, one thing sometimes overlooked is that flocculation only really implies clumping together, it says nothing about sinking. Sometimes even after clumps are forming they can continue to float for quite some time, and no doubt trapping CO2 or other buoyant particles would contribute.
Kev

tourer
Hollow Legs
Posts: 479
Joined: Sun Oct 11, 2009 9:09 pm
Location: spitting distance of the Beacon hotel, home of Ruby red

Re: Seperated yeast?

Post by tourer » Tue Jan 31, 2017 9:50 pm

Kev888 wrote:Yes, for loose dry hopping then a slight bit of stirring in can also help to disperse and submerge them - gently so as not to aerate, and of course with a well disinfected stirrer. With whole hops I usually get a mixture of some sinking and others floating when it comes to racking time. Some people dry-hop in a (boiled) and sometimes weighted bag though, so breaking up beforehand is even more important then. Pellets tend to break apart and disperse a little more easily, and I quite like them for this purpose, but not everyone likes them as much.

WRT the yeast, one thing sometimes overlooked is that flocculation only really implies clumping together, it says nothing about sinking. Sometimes even after clumps are forming they can continue to float for quite some time, and no doubt trapping CO2 or other buoyant particles would contribute.
Hi Kev, i was chilling down the secondary and then had a thought because the the beer was that cold 1.5c the hops just stayed as i left them. so i upped the temperature to 20c and lo behold the beer is as clear as bell and the hops dispersed. I bottled today it smells good and crystel clear. so we'll see. I have a fair few pellets but i need some bags to contain them in the boil/secondary (i'm not a big fan)
Thanks

User avatar
Kev888
So far gone I'm on the way back again!
Posts: 7701
Joined: Fri Mar 19, 2010 6:22 pm
Location: Derbyshire, UK

Re: Seperated yeast?

Post by Kev888 » Wed Feb 01, 2017 3:54 pm

Room temperature (~20c) wort is probably better for extracting dry-hop oils and aromas, so this is quite a common choice, but I wasn't aware of the hops dispersing more easily so thats interesting to hear. (I suppose if the oils are partially holding the compressed hops together then warming and dispersing them could help loosen things). Though there isn't universal agreement on temperature and some people prefer to do it cold (usually for a bit longer) instead. Either way, warmer beer also loses aroma more quickly, so storing it cool afterwards is no bad thing.

Chilling the beer for a little while after fermentation helps things to drop out, but if then warmed up again it can actually seem to clear further, since chill haze will no longer be apparent.
Kev

Post Reply