Re-using Yeast

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hazz20

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Hey all, just wanting to know how to re-use yeast from the fermenter or bottle. Any help would be awesome.

Cheers,

Hazz
 
Ok there are a number of ways.
Re-use the yeast cake, some ppl put the new wort directly on the top of the old yeast cake left in the bottom of the fermenter, some harvest the yeast cake into sterile stubbies etc.
Pour the cake into a stubbie and fill to the top with sterile water. This is especially applicable if you spent $5 on a decent yeast.
Some ppl harvest yeast from commercial brews such as coopers. Beware that some companies use one yeast for brewing and a different for bottle conditoning so the yeast in the bottle may not be the yeast for brewing, therefore possibly the wrong yeast for the brew you want.
Either way, there is a lot on here about harvesting, washing and multiplying yeast.

Word of warning try to match your yeast harvest to your new brew in strength, ie, don't use a stout yeast cake in a weiss or lager.
 
Straight away (same week) - sanitise a container (something with an airtight lid is best) and scoop out or pour out 1/2 a cup of the sludge at the bottom of the fermenter. Tip this sludge into your next beer.

Or you can bottle the same volume of the sludge (I do it into stubbies), cap, and then stick in the fridge. I hear this way can last a few months before needing to build a starter. You can tip this sludge straight into your next beer.
 
I have bottled yeast cake for 3 weeks in the fridge with no problems and don't see longer periods as an issue, i just raise them closer to room temp while i prepare the wort and pitch directly into it. It will work differently than a dried yeast in terms of timing but will work fine.
The yeast cake you use will influence the flavor of the brew.
 
Ive been considering doing this recently 2 as i've started using better yeasts in my brew. I generally leave a brew in the fermenter for 2 weeks(ales) and was wondering if it is ok to re use or will the yeast be dormant by then?

Would i be better off racking to a secondary after a week and then try and salvage it? :beer:

Cheers.
 
Yeast farming guide here by Chiller. This is one way to reuse yeast and store it for a period of time. works great.

Cheers
Gavo
 
I have a stubbie in my fridge which originally contained the cake from my last brew, then I popped it in the fridge for 2 days, poured the liquid into another stubbie, discarded the solid matter left behind and have since been pouring off some of the liquid at the top and topping with cooled boiled water..

That said, i have just realised my next brew day won't be for at least 2 weeks from today... I may be in trouble, given I racked on thursday...
 
Here's a method I posted in another topic.

I have a Morgan's Stockman's Draught with US05 at the moment and I racked to secondary after 4 days and are waiting for it to finish so I can harvest the cake as below.


"QUOTE"

I plan on harvesting a yeast cake soon, maybe a Wyeast 1272 or something similar.

I have read most of the yeast harvesting thread on this forum and others and ran them past my LHBS guy.

He suggested a different way to harvest from the cake and I've decided I might give it a try.

I hope I get this right :huh:

Please note there are many different ways to harvest yeast, and this one seems the easist way for me.

And I quote

" 1) Put down a dark, hoppy brew with intended yeast

2) Let brew for 3-4 days

3) Rack to secondary and throw away original yeast cake

4) Let brew finish and bottle or keg as normal, except leave an inch or two of beer above the yeast cake

5) Swirl to mix yeast cake with remaining beer

6) Bottle into STERILE stubbies, 4 or 5 you be the judge, add appropriate amount of priming sugar and let carb up as per normal, refridgerate once carbed

7) When ready to use, pour off beer into a glass and top up 3/4 with room temp boiled water, recap and shake up.

8) Smell and taste beer poured off, if OK, pitch yeast onto wort


The theory is the beer and CO2 pressure protect the yeast from nasties.

Haven't tried yet.

Will post my results :)

"END QUOTE"
 
There was a discussion a few weeks back that the yeast count in the secondary was lower and the yeast less active, i don't know the truth of it.
I have only harvested the yeast cake twice from the primary and it was successfully pitched both times.
 
I have a stubbie in my fridge which originally contained the cake from my last brew, then I popped it in the fridge for 2 days, poured the liquid into another stubbie, discarded the solid matter left behind and have since been pouring off some of the liquid at the top and topping with cooled boiled water..

That should be quite fine Pollux as what you have described it much the same as chillers article on yeast farming, only you have one sample instead of three or four. Just make sure that you bring its temp up to match the pitching temp and proof the yeast first or make a yeast starter.

Cheers
Gavo
 
I have found recently that the use of just one tablespoon (sanitised spoon) of the yeast cake is enough for a 23L batch of wort.

No ill effects, all good.

My 2c.
 
All sorts of ways of harvesting and re-using yeast, and all of them work to some extent. Rather than rehash all this, as it's a very commonly talked about point, just search and you'll find heaps here.

A couple of general points:

- try to avoid frigging around with harvested yeast, each time you muck with it you potentially damage and/or infect it

- there is some science behind yeast metabolism, so go read a good text like Fix (Principles of Brewing Science) rather than listening to heresay. Like people saying you can pitch on a whole cake - you can, and it will work, but it's the final beer you should be worried about and there are sometimes reasons why you wouldn't overpitch (use too much yeast). And then, sometimes it's good...
 
My idea was to bottle my pale ale brew, pour out a cup of the sludge at the bottom of the fermenter into a sterile stubbie, cap and chuck in fridge, then within a few days have another pale ale brew ready and pour in bottled yeast as I would a normal packet. The thing I'm worried about is any adverse effects. What's the worst it can do? Don't want to steep grain boil hops etc, then stuff it all up by putting in the harvested yeast. If I have to buy another yeast to chuck in because it hasn't worked I can handle that, but to wreck the whole brew, not happy.

Hazz
 
There's a lot of science that has gone into yeast washing etc etc etc.
I agree a small amount of yeast such as a tablespoon will be enough, yeast multiplies, but the lag time could be too long leaving a chance for infection.
Too much yeast may cause your brew to take off like a jet and spout through the airlock.
Yeast will also affect the flavor so using an old yeast cake from a porter is going to greatly affect the blonde you were making.
I can only use my experiences as a guide, i stored my yeast in a sealed sanitized bottle, i took yeast cake sludge and beer to the top of the neck.
Took it out of the fridge an hour or 2 before pitching to let it warm up a little, poured off the beer on top but left enough liquid to swill it around and get most of the sludge suspended in liquid, then poured in.

Whats the worst? Could be dead, have to repitch. OR
Could be infected... spoilt brew and then you need to pay attention to cleaning the sterilizer, but the infections can come from anywhere and i have heard infected yeast smells bad and you will know it when you open the bottle.

Take the risk, it's worth it as it is one more step in making a custom brew. I've enjoyed tasting a hybrid beer that i thought of and engineered by mixing yeasts with kits, i may not be full AG but i'm doing something more than straight K&K.
 
Inspired by a post ages ago on the forum I've invested a few bucks in six urine sample containers you can get from the chemist, sterilized them with sodium met, rinsed with sterile water, poured liquified yeast cake into them, sealed, double bagged each in a freezer bag and fridged in my brewery fridge. Nice and compact and currently living at the back of the fridge just below the rear element in the coolest spot.

specimens.JPG

PS It's a $11 soon to be $15 liquid Wyeast so hopefully this will spread the cost out somewhat ;)
 
Umm just a point Bribie but i wouldn't want to reach into the fridge during a heavy night and find one of those...i may be tempted to give a sample.... ;)

On the serious side i am starting to use Maggi Stock powder containers, about the same size and screw top lid.
 
Umm just a point Bribie but i wouldn't want to reach into the fridge during a heavy night and find one of those...i may be tempted to give a sample.... ;)

That would be perfect to do a VB clone :p
 
Ahh all those youthful years where VB was a constant stream from my nether regions... that's when Swan was exotic and beer was rarely shipped INTO Victoria (always out).
Thank god for Redback brewery....
 

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