Yeast slurry

[ManseMasher]

I've just bottled my Harvey's best. There was about a litre of wort/trub left in the primary, which is now in a pet bottle in the fridge. I have MrMalty's calculator. Question is, should I just use slurry or wash the yeast? Normally just buy more yeast but I'm a cheapskate......

 

[clibit]

There's a guy on JBK from the US of A who knows **** loads about yeast and he is against washing it. He says yeast is best kept in its natural home, the thing it wants to live in -beer. So leave a little beer behind in the FV, swirl it around and stick it in a well sterilised container. Then use Mr Malty to work out how much to use next time.

 

[MyQul]

There's a guy on JBK from the US of A who knows **** loads about yeast and he is against washing it. He says yeast is best kept in its natural home, the thing it wants to live in -beer. So leave a little beer behind in the FV, swirl it around and stick it in a well sterilised container. Then use Mr Malty to work out how much to use next time.

There not being an exact description of what the Mr.Malty calculator defines as slurry seems to have lead to confusion as to what excactly slurry is. If you read post 12 of this thread from home brew talk forum the poster has gotten in contact with Jamil, the creator of Mr Malty to get a defininiton of 'slurry' when applied to the calculator

http://www.homebrewtalk.com/showthread.php?t=143058&page=2

It is seems slurry is the washed out yeast alone not the yeast mixed with the trub.

That being said, I fully accept your assertion that you need to keep your yeast under beer - you linked the post from JBK forum with this guy talking about keeping youryeast under beer in another thread, so I read his explanations.. But that presents a problem. In order to measure how much yeast/slurry you've got you need to rinse your yeast out of the trub and it's REALLY hard to wash yeast out of the trub with beer. I know because I've tried it an just ended up with a big jar of trub(Slid tried it too with the same results as me) and the guy from JBK hasn't detailed a method of how to wash out yeast using beer as AFAIK . Therefore I can only assume you wash the yeast out using water then add the 'covering' of beer later

 

[clibit]

He says to not use water at all. I'll post more later. Thanks for that HBT link.

 

[MyQul]

He says to not use water at all. I'll post more later. Thanks for that HBT link.

Hmm. Wonder how you go about rinsing out the yeast then? :hmm:

 

[clibit]

I think you don't.

"All one needs to do is crop about 350ml of thin slurry, store the crop in a sanitized container in one's refrigerator for up to four weeks (after fours week a starter will need to be made using a small amount of the crop), remove the crop from one's refrigerator, decant the supernatant (clear liquid above the solids), and pitch. It's that simple. There's absolutely no scientific basis for rinsing yeast with and storing it under water."

 

[LarryF]

I'm thinking of having my first crack using the trub to pitch in my next brew on Saturday week. I checked MrMalty and it recommends 88ml. I was thinking of using 100ml but now the definition of slurry has been brought into question any idea how much trub to use. It was a Mauribrew yeast with an OG of 1060.

 

[MyQul]

I think you don't.

"All one needs to do is crop about 350ml of thin "

The problem is aquiring the thin slurry as when you slosh the beer and trub about then leave it for 20 mins to settle out - it doesn't.

 

[ManseMasher]

Mine has been decanted from the fv into a bottle. Left for 30 mins in fridge - definite demarcation between liquid, yeast and trub. Decanted again 5 mins ago, already have a layer of clear beer, a white layer and trub. I'll post a pic in a few minutes.

 

[MyQul]

Mine has been decanted from the fv into a bottle. Left for 30 mins in fridge - definite demarcation between liquid, yeast and trub. Decanted again 5 mins ago, already have a layer of clear beer, a white layer and trub. I'll post a pic in a few minutes.

Cool!! What you want to do now then is decant it again and pour the clear beer and white layer of yeast into another bottle and leave as much of the trub as you can behind

 

[ManseMasher]

I'll give it another 20 mins - not a lot of clear liquid yet!

Second pic - getting better!

 

[MyQul]

How thick is the white layer of yeast? I can't quite tell from the piccy

 

[ManseMasher]

About 2mm give or take a tad, it's a 4ltr jar in the pic, so quite a lot of yeast I would imagine.

 

[MyQul]

Hopefully. You can always do a step up or two if it isn't a pitchable amount

 

[MyQul]

Until I can find and effective way to wash yeast with beer I think I will continue to use water. Even though it's scientifically wrong using water does work.

 

[clibit]

Is washing it important?

 

[MyQul]

Is washing it important?

Not sure how your supposed to measure how much you've got, so you can use a yeast calculator, to pitch the correct amount, if you don't wash it out of the trub.

 

[clibit]

I guess it's all about estimation. Pitching slurry is nothing like an exact science, but I'm more comfortable with leaving the yeast alone than trying to wash it myself.

 

[MyQul]

I guess it's all about estimation. Pitching slurry is nothing like an exact science, but I'm more comfortable with leaving the yeast alone than trying to wash it myself.

Your definately right about pitching rates being all estimation. I've read long threads on the HBT forum by seemingly very knowledgable people who dispute the acurracy of (the MrMalty) online calculators. So in the end it really all comes down to guesstimation work

At the end of the day as long as you put 'some' yeast in your wort your almost certainly end up with beer. Trying to pitch the 'correct' amount of yeast is just tweeking one of the variables in an attempt to make the best beer you can

 

[clibit]

Pitching slurry is a rough way of adding yeast. But every method has a degree of inaccuracy, liquid vials depend on age, as to dry yeast packets. This is surely why dedicated brewers make starters immediately prior to pitching, it gives the most accurate measure of active yeast. I'm not organised or fussed enough to do it. There is margin for error, and we learn what works by using the same method repeatedly.