Rinsing Yeast (in Pictures)

[Yob]

I have read the Yeast book etc, but there seems to me to be a missing link in what I understand..

Q:

Example, Brew has just reached FG..

for accurate repitching/rinsing Its essential to know when the viability date is and I would take that as being when FG is reached, maybe + few days? That being the case is this the best time to harvest the yeast and re-pitch?

Previously I have been CC'ing on the cake and then harvesting but I am looking to refine that to repitching within a day or two of FG then harvest at optimum viability so...

I would assume that when FG is reached any yeast in suspension is largly responsibe for that cleaning action?

If I rack and harvest at this point I kinda recognise that Im selecting for the most flocculent yeast at that point and leaving behind the yeast thats better at cleaning up??

I dunno, I just get confused at that point and cant seem to make my mind up as to when is the best time to harvest the best yeast...

Top cropping aside..

Ive had a few so if that doesnt have logic... please explain.. at what point do you harvest?

:icon_cheers:

 

[Thefatdoghead]

I have read the Yeast book etc, but there seems to me to be a missing link in what I understand..

Q:

Example, Brew has just reached FG..

for accurate repitching/rinsing Its essential to know when the viability date is and I would take that as being when FG is reached, maybe + few days? That being the case is this the best time to harvest the yeast and re-pitch?

Previously I have been CC'ing on the cake and then harvesting but I am looking to refine that to repitching within a day or two of FG then harvest at optimum viability so...

I would assume that when FG is reached any yeast in suspension is largly responsibe for that cleaning action?

If I rack and harvest at this point I kinda recognise that Im selecting for the most flocculent yeast at that point and leaving behind the yeast thats better at cleaning up??

I dunno, I just get confused at that point and cant seem to make my mind up as to when is the best time to harvest the best yeast...

Top cropping aside..

Ive had a few so if that doesnt have logic... please explain.. at what point do you harvest?

:icon_cheers:

I read that book and from what I could gather is that the best time to harvest is when the yeast is at it's peak i.e top cropping would be better than after the yeast has flocculated. Although I read it a few months ago and I very well could be wrong.

 

[Yob]

Top cropping aside..

dude... the question is more about the time of selection from what I have not an 'ideal world scenario'

Cheers though

 

[Dazza88]

I have harvested yeast from my last 6 brews:

How much improvement do you hope to see from changing: "Previously I have been CC'ing on the cake and then harvesting."

I do that or rack to secondary to harvest without much notice of fg day, since i have begun harvesting I am happy with the results every time iirc.

 

[the_new_darren]

Great work there. Just ensure that you dont harvest a mutated strain or wild yeast.

I would suggest only using liquid yeasts 2-3 times

tnd

 

[Yob]

How much improvement do you hope to see from changing: "Previously I have been CC'ing on the cake and then harvesting."

The time it takes to CC I could have the next brew almost to FG again... I hope to speed up the process... as a man who has just ran out of (conditioned) beer I feel it to be important h34r:

 

[psytramp]

i harvest my yeast after 1 week as i have a conical. i have always had a good result so far.

cheers!!

 

[Steve@PMF82]

The time it takes to CC I could have the next brew almost to FG again... I hope to speed up the process... as a man who has just ran out of (conditioned) beer I feel it to be important h34r:

I cant relate to your situation yob as i rarely want to use the same yeast twice in a row. I do what you used to do, conditioning in primary then bottle / keg.
How long this process takes depends on the beer and yeast used. I then wash the yeast down to a small and pretty clean sample which i store in as close to sterile container as i can get for later use in a starter.

But i see what your saying in regards to speeding up your production process. I too sometimes get impatient when im CCing a brew in what is also my ferment fridge(get another fridge? that aint gunna happen haha) and yeah if you rack at FG then you will be leaving behind the less flocculant yeast (that clean up and possibly more attenuation ) and if you keep doing this after a few gen you might have trouble hitting FG targets.

If i wanted to use the same yeast - after FG wait a couple of days for yeast to do their business at ferment temps, then drop temp to as low as possible for couple days(i go minus 1) then rack for further cold conditioning pref in keg and harvest your yeast for reuse. I think at this stage your selection should be pretty good for quite a few generations.
I see it as no different to fermenting a starter and cold crashing it to just use the slurry, which is all i ever do for starting a brew and my lag times are 8 to 10hours max and always a healthy ferment.

 

[pimpsqueak]

A few months ago I harvested and washed some 1272. Seemed to go ok and I ended up with a nice compact, slightly off-white layer of yeast with no discernable trub under nice clean, boiled water.
Got it into a starter last night but this morning I had a bit of a sniff and it smells mighty vegemitey to me. This is autolysis, right?
If so, is the starter going to be useless, or should I soldier on?

 

[manticle]

If it smells crap, don't use it. The risk of ruining the beer isn't worth the saving.

If you are attached to the yeast, let it ferment out, decant, rinse again and see what the next starter smells like (personally I'd just kiss it goodbye - 1272 is easy enough to come by) but use something else in this brew.

 

[phoenixdigital]

We want to keep the middle layer since that contains our yeast in suspension. If you do not leave it long enough you will still have trub mixed in, but if you leave it too long the more floculant yeast will have settled out. The process is a bit of trial-and-error, but by careful observation it's not too hard.

All the more reason to keep the middle layer of yeast.
http://www.nytimes.com/2012/01/17/science/...amp;ref=science

You dont want to be brewing with new forms of multi-cellular life.

 

[Yob]

for the first time in ages I threw a whole trub without risking it... almost threw the whole batch along with it... I cursed and frowned for quite a while... something just wasnt right with the batch I felt, the next morning after botteling I looked at the yeast and again, was darker than normal and... well I dunno, something just not normal.

It was a batch that had an unknown quantum as I was away and the power was out so was uncontrolled... I just felt it was better not to take the risk and pitch a fresh lot.

a batch of beer isnt just the cost of the yeast and grains and hops, it's (for me) the time and emotional involvement as well and I dont want to run the risks of successive brews on a bad batch of cheap yeast.

not to mention risking my favorite fermenter with a serious infection

 

[ASYLUM_SPIRIT]

Ok I think I have almost got the Rinsing Yeast procedure down pat, however I just have one more question if I may just to clarify somthing I'm unsure of.

Where it states "Once the yeast has been rinsed and settled to form a thick compact layer of yeast-slurry (if it is viable and healthy) 50 to 100ml should be adequate for pitching into the next batch of beer"

So all I need for the entire brew is to pitch 50 -100ml of the creamy yeast?

Thanks in advance.

 

[Wolfy]

So all I need for the entire brew is to pitch 50 -100ml of the creamy yeast?

The technical reason/answer to your question can likely be found here: http://www.wyeastlab.com/com-yeast-harvest.cfm (or in the 'Yeast' book).

However, for simplicity, when I re-pitch washed yeast I assume that each 100ml contains 250billion yeast cells.
This is based on the assumption that the yeast is fresh and the slurry measured a thick settled layer on the bottom with no additional trub.

The number of cells recommended for your beer can be estimated by the MrMalty calculator, but based on the assumptions mentioned above, that should be between 50 and 100ml of washed yeast slurry (for most standard batches of Ale).

 

[ASYLUM_SPIRIT]

The technical reason/answer to your question can likely be found here: http://www.wyeastlab.com/com-yeast-harvest.cfm (or in the 'Yeast' book).

However, for simplicity, when I re-pitch washed yeast I assume that each 100ml contains 250billion yeast cells.
This is based on the assumption that the yeast is fresh and the slurry measured a thick settled layer on the bottom with no additional trub.

The number of cells recommended for your beer can be estimated by the MrMalty calculator, but based on the assumptions mentioned above, that should be between 50 and 100ml of washed yeast slurry (for most standard batches of Ale).

Thanks mate I will follow the links!!

 

[Yob]

also, when using Mr Malty, you need to plug in your "harvest date" to determine viability... This is not always when the yeast is "actually" harvested... in essence, its when the yeast were lest active, for me it's usually 2 weeks prior to actually harvesting it, as in the 3 week cycle, loosely, 1 week to ferment, 1 week to condition, 1 week to cold condition. So at the end of cold conditioning I will plug in 2 weeks prior as my harvest date.

Not knowing this the first few times, I got it wrong I think and the beer suffered a bit for it.

Live and Learn.

Yob

ed: clarity

 

[hando]

Hey Guys,

I used this method to reuse my yeast WLP830.

Some differences I've noticed are that the amount of yeast I collected was so small compared with the thick layer in Wolfy's photos. I've stored it in a White labs test tube, and the amount of yeast settled in there is approx. 1/4 teaspoon.

Secondly, when I've reused it in 2 subsequent brews I noticed that the beer was cloudy, even after filtering. I'm still doing K&K at this stage and I doubt it's chill haze. I'm thinking that the cloudiness is from the yeast, and that the yeast which I "selected" when harvesting, was the less flocculant yeast, and that's causing the cloudiness.

When making the starter on the stir plate in about 2litres of wort, I've noticed that after turning the stir plate off and waiting a couple of hours there was a cloudy mixture throughout the starter with only 3-5mm of unclouded liquid at the top, and only a very fine dusting of yeast at the bottom.

Does that sound normal? Anyone got any input would be fantastic.
Cheers

 

[Yob]

Hey Guys,

I used this method to reuse my yeast WLP830.

Some differences I've noticed are that the amount of yeast I collected was so small compared with the thick layer in Wolfy's photos. I've stored it in a White labs test tube, and the amount of yeast settled in there is approx. 1/4 teaspoon.

Secondly, when I've reused it in 2 subsequent brews I noticed that the beer was cloudy, even after filtering. I'm still doing K&K at this stage and I doubt it's chill haze. I'm thinking that the cloudiness is from the yeast, and that the yeast which I "selected" when harvesting, was the less flocculant yeast, and that's causing the cloudiness.

Cheers

how thick was the trub you were rinsing? A trub that is quite thick in solution will not let you see the propper separation. This can lead you to select only the least flocculent yeast in solution which could lead to your second issue.

When rinsing you should have about 4 x rinsing water over whatever volume of slurry you are rinsing, I often find that if I've got too thick a slurry the separation is not all that evident after 20 mins, so will split again into 2 vessels and go again, normally this is enough to get it right.

Here is a link to the BN Podcast on Rinsing Yeast LINKY If you have a spare hour have a listen as it's very informative and helps with understanding. They discuss what happens when less flocculent yeast is selected and quite sounds like your problem.

Hope this helps

Yob

 

[Newbee(r)]

how thick was the trub you were rinsing? A trub that is quite thick in solution will not let you see the propper separation. This can lead you to select only the least flocculent yeast in solution which could lead to your second issue.

When rinsing you should have about 4 x rinsing water over whatever volume of slurry you are rinsing, I often find that if I've got too thick a slurry the separation is not all that evident after 20 mins, so will split again into 2 vessels and go again, normally this is enough to get it right.

Here is a link to the BN Podcast on Rinsing Yeast LINKY If you have a spare hour have a listen as it's very informative and helps with understanding. They discuss what happens when less flocculent yeast is selected and quite sounds like your problem.

Hope this helps

Yob

Interested in whether people are growing starters and then harvesting and storing rather than post fermentation harvest and rinsing? I have been doing this for a while, just bottled a dozen 75 ml jars with Ringwood. Is there any issues doing it this way I need to be aware of? Also, curious about length of viability for these in the fridge - have seen somewhere 3 months?

 

[Swanstar]

Thanks Wolfy,

Very good and informative thread, I've been harvesting my yeast cakes for a while but haven't been rinsing and I've found that it tends not to last very long even in the fridge, will be trying this tonight.

Cheers,


Swanny