Washing and reusing yeast

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Poshlloyd

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Hi guys,

Quick stupid question.

I want to start collecting and washing my yeast after this batch.

Can I do this after using dry yeast in my brew or is it only following liquid yeast?

Cheers
 
Cheers
I'll recover my Nottingham after this batch, then use a starter with it next time.
 
I did some washing last night for the first time after moving a batch!
This was dried us-05. I collected five bottles worth and will be brewing again this week but will be making a starter.

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I did some washing last night for the first time after moving a batch!
This was dried us-05. I collected five bottles worth and will be brewing again this week but will be making a starter.

The only reason to make a starter is if you a) washed the yeast out over 4 weeks previous to pitching b) you didn't wash enough yeast out for a pitchable amount

Other than that your just making extra work for yourself and possibly overpitching
 
Cheers MyQul
I am interested in this subject as it would be nice to build up a few different strains of yeast and from a money saving point of view.
How do I determine how much of a washed and stored yeast to pitch in a 10 litre batch?
 
Just scoured the how to board and couldn't see one, so could someone post a how to on yeast washing?

I'm fed up of buying yeast esp as I'm mostly doing 10L brews and using a new pack of sa-05 each time. Hardly hugely expensive at £2.50 a pop, but I'd rather keep my own batches running, it will feel a bit more authentic (like in days of yore when then brewing stick was passed from batch to batch).
 
Just scoured the how to board and couldn't see one, so could someone post a how to on yeast washing?

I'm fed up of buying yeast esp as I'm mostly doing 10L brews and using a new pack of sa-05 each time. Hardly hugely expensive at £2.50 a pop, but I'd rather keep my own batches running, it will feel a bit more authentic (like in days of yore when then brewing stick was passed from batch to batch).

1)Boil and cool 1L-2L of water.
2) Rack as much beer off your yeast cake s you can
3) Chuck the 2L of water into the FV
4) Swirl around lots
5) Leave for 20 mins. The trub will have fallen to the bottom and you'll be left with suspended yeast
6) Decant suspended yeast into a sanitised jar.
7) Job Done - you can now put it in the fridge to compact down so you can measure how much yeast you have
 
Cheers MyQul
I am interested in this subject as it would be nice to build up a few different strains of yeast and from a money saving point of view.
How do I determine how much of a washed and stored yeast to pitch in a 10 litre batch?

http://www.mrmalty.com/calc/calc.html

Click on the repitch from slurry tab and move the slider over to 4.5. This represents washed yeast that has been in the fridge for a few days and is compacted down in the bottom of the jar/bottle/etc
 
Thankyou for your reply MyQul your information is very helpful!
As an example then for a 10 litre batch at a OG of 1.050 the calculator comes out at 25ml of yeast needed.
So if I decanted the clear liquid off of one of the bottles I have and then gave the bottle a thorough shake to suspend the yeast I could then pitch 25 ml of that liquid. Does that sound about right? And I am good to go without making a starter for up to 4 weeks after this time a starter should be made?
 
Just scoured the how to board and couldn't see one, so could someone post a how to on yeast washing?

I'm fed up of buying yeast esp as I'm mostly doing 10L brews and using a new pack of sa-05 each time. Hardly hugely expensive at £2.50 a pop, but I'd rather keep my own batches running, it will feel a bit more authentic (like in days of yore when then brewing stick was passed from batch to batch).

Washing the yeast is easy and I've now done 9 brews from 1 bought US 05 sachet.

Did the first brew without the Partial Mash addition, as it adds a LOT of trub material.

Washed the trub from the first kit brew into a 2L pop bottle and then, after a week or so, and another wash, into as many 250ml lemonade bottles as it filled. Plenty of yeast to give a great start, even after 2 months in the fridge. Absolutely no problems.

Really like the US 05 yeast - it gives a clean taste and a clear glass. Only downside is that it does take 2 weeks to clear in the primary FV.

Racking to a secondary for a third week is also highly recommended.
 
Here is a link to a thread on another site:

http://www.homebrewtalk.com/showthread.php?t=41768

But basically you pour some some water onto the yeast residue after the initial ferment, swirl it around a bit in the bottom of the FV, and the pour the result into a 2L Pop bottle, via a funnel. You don't need all the residue, as the yeast will tend to be on the top of any other stuff.

This will then settle out and you pour off some of the top liquid to leave 2 layers of yeast (on top) and gunk (on bottom). Swirl it around a bit with some more water. Then try to leave the gunk out of the water plus yeast that goes into the small bottles.

250ml bottles that once held lemonade are great for this, since no amount of unwanted fermented sugars can do any harm, and they are unlikely to result in serious under or over ptiching. The 250ml bottle should end up as roughly 15-20% yeast (and other stuff the washing didn't sort) and the rest water.

On the brew day, take the little bottle out of the fridge and give it good shake and leave it in the warm.
 
Thankyou for your reply MyQul your information is very helpful!
As an example then for a 10 litre batch at a OG of 1.050 the calculator comes out at 25ml of yeast needed.
So if I decanted the clear liquid off of one of the bottles I have and then gave the bottle a thorough shake to suspend the yeast I could then pitch 25 ml of that liquid. Does that sound about right? And I am good to go without making a starter for up to 4 weeks after this time a starter should be made?

Your first calculation is correct 25ml for a 10L @1.050. However you need to pitch 25ml of the compacted yeast before shaking to suspend. You've put "I have and then gave the bottle a thorough shake to suspend the yeast I could then pitch 25 ml of that liquid", which is a different amount as you have 25ml of not-compacted-slurry which will give you less yeast. Hope that's clear

I measure by taking an Identical jar to the one I've got the yeast compacted in then putting them side by side full the second jar with water to the exact same level as the one with the yeast in then measure how much water I have in the second jar to see how much yeast I have. Then swirl to suspends and pitch.

Everything I've read says the yeast will be fine in the fridge up to a month then you need to make a starter. I never really go longer than about 1-2 weeks tbh as I bottle and harvest yeast one week then brew a repitch the next week.

Remember when using the yeast calculator to plug in the 'harvest date' as you'll need more yeast say if you havested a month ago than if you harvested yesterday
 
It's much better, I believe, not to add water to the fv, but to leave some wort behind to mix the yeast with. Keep the yeast in it's natural environment.
 
Thanks all. How long will it live in the fridge for? I rarely start a brew the day of bottling the last one. A month? Presumably then a starter would be a good idea?
Think when I give this a go I'd best have a pack on standby!
 
Your first calculation is correct 25ml for a 10L @1.050. However you need to pitch 25ml of the compacted yeast before shaking to suspend. You've put "I have and then gave the bottle a thorough shake to suspend the yeast I could then pitch 25 ml of that liquid", which is a different amount as you have 25ml of not-compacted-slurry which will give you less yeast. Hope that's clear

I measure by taking an Identical jar to the one I've got the yeast compacted in then putting them side by side full the second jar with water to the exact same level as the one with the yeast in then measure how much water I have in the second jar to see how much yeast I have. Then swirl to suspends and pitch.

Everything I've read says the yeast will be fine in the fridge up to a month then you need to make a starter. I never really go longer than about 1-2 weeks tbh as I bottle and harvest yeast one week then brew a repitch the next week.

Remember when using the yeast calculator to plug in the 'harvest date' as you'll need more yeast say if you havested a month ago than if you harvested yesterday

Got it ! What I couldn't figure out is how to calculate how much was in the bottles. Add 25ml of water to the bottom of a bottle and match it!
Cheers guys your knowledge is always welcome!
 
That makes for interesting reading ,Thanks Clibit!
I have just measured what I have in the bottles from my harvest and it seems more or less around the 20 -25ml mark . Now what I have in each bottle only represents a small percentage of what was in the bottom of the FV after I had decanted the beer off. I know that it is common for people to pitch a new batch straight onto a yeast cake ,surely this is overpitching? I suppose my question is, How much is too much?
 
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