Re-sign liquid yeast

[tricey27]

Hi, I brewed a Worthington White Shield on Friday, it's still primary fermenting well but just want to know when I should transfer to keg and how I go about reusing the yeast. If someone could help me with this information it would be greatly appreciated. Cheers

 

[LarryF]

Tricey, there's a whole world of re-using yeast but I try and keep it simple. I think the most important thing is that whatever you store the re-used yeast in or anything that comes into contact with it must be absolutely sterile. I clean and steriise one extra bottle but I don't prime it and I put a sterile lid on it as soon as I've washed it out. When I've finished bottling my beer I swirl around the trub in the bottom of the FV and using a sterile funnel I fill a 500ml bottle about a third with the trub. I put the lid on and put it to one side at room temperature as I'll be using it on the same day. When my new wort is at about 23-24c I fill the bottle with the new wort, give it a gentle shake and then pour the contents into the FV. Everytime I've done this it's worked a treat, I do believe that you can keep the trub in the fridge for 2 weeks odd with no detremental effects but do bring it back to room temperature before using.

 

[mike77]

Once I've removed my beer from the fermenter I swirl the remaining contents of the fermenter around and then fill serialised jam jars and keep it in the fridge. I believe it can last for months. When I want to use it I either scoop a few teaspoons into a 1l starter or simply pour off the beer from the jar and tip the contents into the fermenter.

 

[tricey27]

Thanks for that info lads, is the "trub" the thick yellowy liquid thats always left in the bottom of the FV? If so that sounds fairly simple, i shall give it a go once my worthingtons has finished fermenting. Many thanks for your help. :)

 

[mike77]

Yes that's the trub. It's a mix of live and dead yeast. Some people separate the live and dead yeast but I don't think it's necessary, it's more effort and more chance of infecting things.

 

[MyQul]

Yes that's the trub. It's a mix of live and dead yeast. Some people separate the live and dead yeast but I don't think it's necessary, it's more effort and more chance of infecting things.

Trub is made up of all kinds of '****', live yeast cells, dead yeast cells, stressed yeast cells, protiens/break material, hop debris, etc.

The main reason you may want to rinse the live yeast out is all the '****' may have a detrimental flavour impact on the beer your pitching the trub into

 

[stevej]

+1 on ^.........

 

[tricey27]

Great thanks, how do i "rinse" the live yeast from the dead please? Just so i know the process. Thank you

 

[nbpicklesno2]

Pour some warm water in a jam jar, put in the same amount of trub and shake it. After twenty minutes at room temperature, the trub will sink to the bottom and the live yeast will remain in suspension at the top. Decant the lighter top liquid and that's your basis for your starter.

Some people don't like using water but it works well. Might be good to sterilise it by boiling and letting it cool to room temperature first.

 

[MyQul]

While rinsing yeeast with water will work in a similar way to just pitching trub directly will also work, but your just swapping one bad practice for another.

Using water to rinse yeast is bad practice for two reasons:
1) Water isn't sterile. Even if you boil it it still has bateria spores in it which can only be killed by autoclave/pressure cooker.
2) Even if you completely sterilize your rinsing water, yeast need nutrients which water doesn't provide. Even when it's kept in the fridge yeast still metabolises (only much slower)nd requires those nutrients. The best medium to keep yeast under is beer.

To rinse yeast using beer, after racking your beer off the yeast slowly swirl the FV then leave for 10-20mins so the heavy trub settles out. You should then be able to decant off the remaining beer (with yeast suspended in it).

Tbh I never could make the above technique work for me and always just ended up with a jar full of trub so I use the following technique:

*Harvest some trub
*Make a 2L starter (200g DME/2L water - boiled for 15mins to sterilize then cooled)
*Put about 400ml of trub and the starter wort in a 5L water bottle and ferment out over a couple of days, shaking the water bottle at least 4 times per day.
*Once the starter has fermented out get a couple of 2L water bottles
*Shake the starter to suspend everything in the spent wort.
*Leave it on the side for 20mins and the heavier trub will settle out to the bottom of the water bottle leaving the yeast suspended in the spent wort
*Decant the spent wort/suspended yeast into the 2x2L water bottles.
*Put the 2L water bottles in the fridge to crash out the yeast so you can now measure how much yeast you've got

 

[nbpicklesno2]

Tbh I never could make the above technique work for me and always just ended up with a jar full of trub so I use the following technique:

That's exactly why I don't use this method. Water works in my method above as what is left is not 100% water but a weak beer solution which, as you say, is what yeast should be stored under.

Well, it works for me.

 

[mike77]

Trub is made up of all kinds of '****', live yeast cells, dead yeast cells, stressed yeast cells, protiens/break material, hop debris, etc.

The main reason you may want to rinse the live yeast out is all the '****' may have a detrimental flavour impact on the beer your pitching the trub into

Thing is that I don't think enough is being pitched to change the flavour. If you pour off the old beer first you are not carrying much over. If you make a starter with the collected trub then you are only carrying several teaspoons over and effectively washing the yeast and doing a viability check just prior to using it. I've read numerous people report that there is no detectable off flavour and that includes people brewing side by side comparisons with washed and unwashed yeast.

Also the trub (dead yeast, etc) also acts as nutrient for the live yeast and the old hopped beer collected has antibacterial properties. So this seems like an easy and natural way to store yeast fairly long term in the fridge.

 

[MyQul]

That's exactly why I don't use this method. Water works in my method above as what is left is not 100% water but a weak beer solution which, as you say, is what yeast should be stored under.

Well, it works for me.

More power to you for whatever works for you. I've rinsed yeast with water and found it work well too,in fact as far as the rinsing process goes water works better than beer/starter wort.

Tbh if your only storing the yeast for a day or two I don't think there would be any noticible effect.

I'm just of the personal opinion that the yeast is THE most important thing in brewing so try to treat my yeast as sypathetically as possible. So as previously mentioned other techniques work with probably no decernable negative effect but I just like to be 100% sure by using the best methods I can find

 

[MyQul]

Thing is that I don't think enough is being pitched to change the flavour. If you pour off the old beer first you are not carrying much over. If you make a starter with the collected trub then you are only carrying several teaspoons over and effectively washing the yeast and doing a viability check just prior to using it. I've read numerous people report that there is no detectable off flavour and that includes people brewing side by side comparisons with washed and unwashed yeast.

Also the trub (dead yeast, etc) also acts as nutrient for the live yeast and the old hopped beer collected has antibacterial properties. So this seems like an easy and natural way to store yeast fairly long term in the fridge.

I think your probably right in that your not carrying much over by say pitching 400ml of trub into 23L of beer but I like to pitch yeast as healthy and viable as possible

I think making a starter with the collected trub is the best way to use it and is what I do myself

I agree, storing the yeast in the trub in the fridge (the same as storing it under beer/starter wort) is the best way to fridge store. It's storing it under water (for more than a day or two) Is what I wouldn't do

 

[nbpicklesno2]

I'm just of the personal opinion that the yeast is THE most important thing in brewing so try to treat my yeast as sypathetically as possible.

Couldn't agree more. I've got four vials of yeast in the fridge stored using the method I use, that have been there for two months or so due to getting myself a new job and not having the time to use them.

I'll see how they work (if they do, but I only need a couple of viable cells) when I make a starter in the next week of so. I'm not imagining any problems but you never know.

 

[JapanBrew]

Well, I washed a little bit but left some old beer in. Mostly took the top good yeast and moved it over to another jar. But I pitched it within a few hours so no harm done. It's bubbling away nicely right now.
Got another jar ready in the fridge for today's brew but I might cut in in half with some DME. I'm only brewing 7 liters so don't need 450 ml of yeast!!

 

[Hoppyland]

I tend to use only top-fermenting yeasts, so I don't use the trub at all, but skim yeast off the top during the first, very vigorous fermentation. For back-to-back brews I just pitch using this skimmed yeast as it is. Otherwise, I keep it in a sterile jar in the fridge, then make a starter from it.

 

[cheapbrew]

The nanobrewery blogger posted his method in his nanobrewery thread
http://www.thehomebrewforum.co.uk/showthread.php?p=546425#post546425