Washing yeast with beer instead of water?

[user 214470]

I'm about to start washing and storing some yeast in the fridge for future use.
I was always wondering - why do you need to use sterile water for yeast washing, why can't we just use the beer that yeast naturally created as their "medium" (with a certain pH and even some preservative alcohol).

It would not even be "washing", I'm thinking - just swirl/decant the yeast-beer mix several times to get rid of the trub, and your'e left with yeast layer at the bottom, and clear beer layer on the top. Are there any dowsides to that vs. washing with sterile water? Storage longevity?

 

[ccous]

You’re absolutely right. The finished beer is a much better medium for storing the yeast. Just swirl, pour, and store.

 

[user 214470]

So why the hell in every "how to wash yeast" article and video they tell you to use sterile (boiled) water?
It would also be easier and faster without using the water... But maybe I don't know something, maybe water cleans the yeast from certain harmful (to them) substances? (I'm looking to be able to store the yeast for about a year in the fridge, before making a starter).

 

[kh54s10]

Save yeast from beers that are not highly hopped, or bag the hops. Save the yeast cake in sanitized jars. Don't even bother trying to "wash" the yeast. Pitch into a new batch with 1/4 to 1/3 of the yeast saved.

You can save yeast this way for several months.

 

[Vale71]

But maybe I don't know something, maybe water cleans the yeast from certain harmful (to them) substances?

Such as alcohol? You just nailed it.

P.S. Osmotic pressure plays an important role in long-term storage as well.

 

[kh54s10]

I believe that it has been proven that it is better to leave the yeast in beer than in water. I don't remember where I saw that but I do know it was not just one article, it was several.

 

[Vale71]

I believe that it has been proven that it is better to leave the yeast in beer than in water. I don't remember where I saw that but I do know it was not just one article, it was several.

For short-term storage, yes. Short-term is 48 to 72 hours.

For long-term storage alcohol and osmotic pressure will kill off most of the yeast.

P.S. I'm assuming saline solution being used for long-term conservation. Pure water is probably just as unsuitable as beer.

 

[Carolina_Matt]

I actually did this yesterday, for the first time. There was a little bit of beer left in the bucket, so I gave it a little swirl and poured it into a sanitized mason jar. After 24 hours in the fridge, this is the result.

At this point, I'm not sure what to do with it though. I thought there would be three layers - liquid, yeast and trub - but I only see two layers. Either I got a lot of yeast and no trub, or a lot of trub but no yeast?

 

[IslandLizard]

To separate yeast from the trub after harvesting from a batch of beer, just strain the trubby yeast slurry through a very fine mesh hop bag, or a piece of voile placed in a funnel. That way you lose much less yeast than with rinsing, and the little trub that is fine enough to make it through, well so be it.

I've been storing yeast slurries under the starter beer they came from. Yeast harvested from batches, after straining, gets stored under the beer it came from. Seems to be fine for 6 months, within that time it's either being reused or dumped on the compost heap.

 

[kh54s10]

For short-term storage, yes. Short-term is 48 to 72 hours.

For long-term storage alcohol and osmotic pressure will kill off most of the yeast.

P.S. I'm assuming saline solution being used for long-term conservation. Pure water is probably just as unsuitable as beer.

I know from personal experience that you can go much longer than 48 -72 hours and not kill off most of the yeast. I have used slurry saved in a mason jar at over a month stored in the refrigerator.

 

[IslandLizard]

I actually did this yesterday, for the first time. There was a little bit of beer left in the bucket, so I gave it a little swirl and poured it into a sanitized mason jar. After 24 hours in the fridge, this is the result.

At this point, I'm not sure what to do with it though. I thought there would be three layers - liquid, yeast and trub - but I only see two layers. Either I got a lot of yeast and no trub, or a lot of trub but no yeast?

You got 2 layers, yeast and trub are mixed together, beer on top. That yeast is fine to use as is. If that's the whole cake from a batch, repitching 1/5 - 1/3 of it is plenty for a similar volume batch of 1.060 wort or less.

Store it in the fridge. You may want to slightly loosen the band for the first few weeks to vent any outgassing.

 

[user 214470]

Well, one local homebrewer just mentioned that he once stored a yeast cake (unwashed) in the 55-65'F basement for 2 years, and then revived the yeast by making a starter - although he needed to make a starter three times to bring them to life properly.

So I'm actually baffled if should I wash or just decant from trub...

 

[Carolina_Matt]

You got 2 layers, yeast and trub are mixed together, beer on top. That yeast is fine to use as is. If that's the whole cake from a batch, repitching 1/5 - 1/3 of it is plenty for a similar volume batch of 1.060 wort or less.

Store it in the fridge. You may want to slightly loosen the band for the first few weeks to vent any outgassing.

Thanks, I'll give it a shot. I planned on brewing a batch today, although I'm feeling pretty lazy and may wait until next Friday.

It wasn't the whole cake from the batch I kegged yesterday. I'd say it was maybe half or so. I filled up one jar, and tossed the rest.

So would you recommend I pour out the beer on top, and pitch the yeast/trub directly?

 

[IslandLizard]

Thanks, I'll give it a shot. I planned on brewing a batch today, although I'm feeling pretty lazy and may wait until next Friday.

It wasn't the whole cake from the batch I kegged yesterday. I'd say it was maybe half or so. I filled up one jar, and tossed the rest.

So would you recommend I pour out the beer on top, and pitch the yeast/trub directly?

As long as you swirled up that yeast cake well, so all of it was in suspension when you poured it out, you'll have a homogenized, representative yeast culture there, containing everything from early, more flocculent workers to slower, less flocculent cleaner uppers and conditioners.

If that was only about half the cake, that slurry contains a fair amount of trub, and will be good for about 2 batches the way it is.

Leave the beer on top, it slows down oxidation of the slurry (less air in headspace).

Before you pitch, you should let the jar come back to room temps, within 5-10°C of the wort temps you're pitching into. Stir and pour half into your fermenter. Put the rest back into the fridge for another batch. Or pour the remainder into a half sized jar for the 2nd pitch.

Next time maybe divide them up right after harvesting, so you have one jar for each subsequent pitch.

 

[IslandLizard]

So I'm actually baffled if should I wash or just decant from trub...

What you're doing is yeast rinsing not washing, which is the term for a whole different process.

In general, yeast rinsing is not needed, and can be counter productive as a lot of the yeast is lost (more than half) during the process. Also storing in/under water is not as good as under a low gravity beer or even better, a light saline solution.

Not sure what you mean with 'decant from trub,' trub and yeast are generally mixed together, like what you see in the picture from @[URL='https://www.homebrewtalk.com/forum/members/carolina_matt.251916/']Carolina_Matt in post #12[/URL].

 

[user 214470]

What you're doing is yeast rinsing not washing, which is the term for a whole different process.

In general, yeast rinsing is not needed, and can be counter productive as a lot of the yeast is lost (more than half) during the process. Also storing in/under water is not as good as under a low gravity beer or even better, a light saline solution.

Not sure what you mean with 'decant from trub,' trub and yeast are generally mixed together, like what you see in the picture from @Carolina_Matt in post #12.

Please excuse my bad English and sorry if not using the correct terms... (I'm European, so my English is not very "rich"...). What I meant to say, is when you swirl up the yeast cake/beer to homogeneous substance, after about 30 minutes layers usually start to separate - trub at the bottom, yeasty beer in the middle, and cleared beer at the very top. So, once you see that, just pour off the two top layers and dump the trub at the bottom. Then just leave it in the fridge and the yeast will eventually settle at the bottom, with clear beer on top.

 

[kh54s10]

When you rinse yeast you add water or beer, stir it up really well then put it in the refrigerator to settle. If done well you usually get three layers. The top is the water or beer. Then there should be a thin line of creamy white. This is the yeast. The bottom is the trub. It should be darker maybe green from hop debris. But there is a lot of yeast in the the trub which is why yeast rinsing is becoming less popular. And it is an unnecessary step.

If you let it settle you can just pour off the clear beer on top, then swirl up the rest to loosen it then pitch into the new batch

 

[IslandLizard]

Please excuse my bad English and sorry if not using the correct terms... (I'm European, so my English is not very "rich"...). What I meant to say, is when you swirl up the yeast cake/beer to homogeneous substance, after about 30 minutes layers usually start to separate - trub at the bottom, yeasty beer in the middle, and cleared beer at the very top. So, once you see that, just pour off the two top layers and dump the trub at the bottom. Then just leave it in the fridge and the yeast will eventually settle at the bottom, with clear beer on top.

No, not bad English, your English is very good, as rich as many native speakers. I wouldn't have known if you hadn't told us.

The term yeast washing is often unilaterally used when referring to yeast rinsing. They are similar, but yeast washing is rarely done, especially by homebrewers, but some breweries may. It involves using an acid and needs to be performed right before pitching.

Are those jars straight dumps from your fermenter or was the yeast rinsed once or twice already, since?
I'm asking, because that's very clean yeast already! That settled 1 cm layer of slurry must contain a large percentage of flocculated yeast, judging by its color and overall look. It may well be 70% yeast and 30% trub. I would not wash that down the drain. I'd keep all of it.

 

[deadwolfbones]

Well, you can apparently save yeast in alcohol for at least 133 years without killing all of it: https://www.apnews.com/3583b5a1836f478e939715a7ccfb2c9e

 

[user 214470]

Are those jars straight dumps from your fermenter or was the yeast rinsed once or twice already, since?
I'm asking, because that's very clean yeast already! That settled 1 cm layer of slurry must contain a large percentage of flocculated yeast, judging by its color and overall look. It may well be 70% yeast and 30% trub. I would not wash that down the drain. I'd keep all of it.

Well, actually this isn't my image, it's just an image from internet to illustrate my thoughts, but I've seen numeral youtube videos about yeast rinsing (that they usually call washing btw) where the slurry looks/behaves like that.
I'm bottling Kveik tomorrow and going to harvest some yeast for storage, and I'm curious to see if my jars look similar. Oh, and since Kveik can be dried, I might as well go that way - some say it can be stored at least 20 years dried and frozen

On another note, you're saying you would not wash the trub down the drain - do I understand correctly that the trub is not harmful for yeast storage? (assuming I'm always making starters when re-using the yeast).

 

[GnenieGone]

Shoot I just started storing the entire yeast cake into a sanitized bomber. Figure it'll be happy there. Great minds think alike! [emoji6]

 

[user 214470]

Well, you can apparently save yeast in alcohol for at least 133 years without killing all of it: https://www.apnews.com/3583b5a1836f478e939715a7ccfb2c9e

This actually is fascinating! I've seen a NatGeo documentary where a few years ago they found a few crates of 1906 Scotch whisky in the Antarctic expedition site in South Pole that belonged to polar explorer Ernest Shackleton - the whisky was still good after more than 100 years... But beer is the whole new level, as the yeast still came to life after 133 years!

 

[deadwolfbones]

This actually is fascinating! I've seen a NatGeo documentary where a few years ago they found a few crates of 1906 Scotch whisky in the Antarctic expedition site in South Pole that belonged to polar explorer Ernest Shackleton - the whisky was still good after more than 100 years... But beer is the whole new level, as the yeast still came to life after 133 years!

There's actually been even older, too: http://www.bbc.com/travel/story/20181206-a-beer-brewed-from-an-old-tasmanian-shipwreck

 

[IslandLizard]

On another note, you're saying you would not wash the trub down the drain - do I understand correctly that the trub is not harmful for yeast storage? (assuming I'm always making starters when re-using the yeast).

In general with this procedure, after decanting (and saving) the liquid on top, containing the suspended yeast, the bottom layer (trub) is leftover, and usually discarded. Now that trub layer may contain a lot of yeast, possibly more than what's in suspension...

In this illustration, that 1 cm 'trubby' bottom layer is probably half yeast, it looks very clean (light beige). So some judgment may be in order.

From what I understand, trub is generally not detrimental to yeast's health during storage. Not sure about more extreme cases.

 

[Jayjay1976]

For me, bigger jars are just a bit more expensive than small ones, and im a firm believer that washing of any kind involves unnecessary risk of contamination. Beer protects yeast.

 

[user 214470]

Now that trub layer may contain a lot of yeast, possibly more than what's in suspension...

I have no doubts that trub layer contains a lot of yeast, but my other question is - isn't the yeast in suspention (with trub discarded) not enough for storage, having in mind that I'll make a starter anyway? I'd like to believe the less contaminants (trub), the less chance for decay/contamination in the long term of storage.

 

[kh54s10]

I have no doubts that trub layer contains a lot of yeast, but my other question is - isn't the yeast in suspention (with trub discarded) not enough for storage, having in mind that I'll make a starter anyway? I'd like to believe the less contaminants (trub), the less chance for decay/contamination in the long term of storage.

If you are making a starter you really only need a few yeast cells to start from. But, then it is difficult to decide where your starter stands in regards to cell counts.

IMO, You have a better chance of contaminating your yeast by trying to remove the trub.

 

[Jayjay1976]

Keep in mind the natural preservative effect of hops; the alpha acid lowers pH which together with ethanol makes for a less hospitable environment for growth of unwanted microbes than the close to neutral pH of yeast washed with distilled water.

I'm bottling a double IPA today and harvesting most of the trub to save the Voss kveik for future batches; the high IBU's and ABV mean I will have little concern about contaminants gaining a foothold. In fact, instead of isolating the saved yeast in a bunch of tiny jars, I'm going to keep it in a big jar and spoon some out as needed for making starters. It should last me a good long while, and im also going to dip some popsicle sticks in the slurry and let them air dry then store in the freezer as a backup. The ultra hardy Voss strain along with the Hornindal I'll harvest next weekend from a 1.070 stout will both become my house strains, replacing the 3522 and 1762 I've been using.

 

[user 214470]

I also bottled Voss Kveik yesterday, and going to harvest in about an hour. For Kveik, I'm going to dry it as it's capable of it.

 

[Vale71]

Keep in mind the natural preservative effect of hops; the alpha acid lowers pH which together with ethanol makes for a less hospitable environment for growth of unwanted microbes than the close to neutral pH of yeast washed with distilled water.

Provided you have properly washed your yeast before storing it there will be nothing but yeast in the suspension. What should these other microbes you mention then actually feed on? Also, considering that the microbes we need to be most worried about are the ones that actually feed on beer, how is leaving beer in the mix for them to feed on going to prevent them from growing?

 

[Jayjay1976]

Provided you have properly washed your yeast before storing it there will be nothing but yeast in the suspension. What should these other microbes you mention then actually feed on? Also, considering that the microbes we need to be most worried about are the ones that actually feed on beer, how is leaving beer in the mix for them to feed on going to prevent them from growing?

Beer magic

 

[Vale71]

All hail!

 

[Carolina_Matt]

As long as you swirled up that yeast cake well, so all of it was in suspension when you poured it out, you'll have a homogenized, representative yeast culture there, containing everything from early, more flocculent workers to slower, less flocculent cleaner uppers and conditioners.

If that was only about half the cake, that slurry contains a fair amount of trub, and will be good for about 2 batches the way it is.

Leave the beer on top, it slows down oxidation of the slurry (less air in headspace).

Before you pitch, you should let the jar come back to room temps, within 5-10°C of the wort temps you're pitching into. Stir and pour half into your fermenter. Put the rest back into the fridge for another batch. Or pour the remainder into a half sized jar for the 2nd pitch.

Next time maybe divide them up right after harvesting, so you have one jar for each subsequent pitch.

I brewed my batch on Sunday - a Bell's Two Hearted recipe from their website. I did as you suggested and stirred everything, then poured half into the fermenter. I figured it would take off right away, but there was no bubbling when I went to bed.

I woke up at 4am to get my daughter some medicine and saw some bubbling. Got home from work Monday night and the airlock was full of wort - it was going nuts! Replaced the airlock, and the next one filled up too! Here were are 3 1/2 days later, and it's still bubbling like crazy. I think it's safe to say that the yeast worked It took so little effort to just take some of trub and put it into a mason jar, rather than boiling up water, letting it cool, swirling it around, etc.

I'll need to put together a blowoff tube for future batches based on what I've been seeing.

 

[IslandLizard]

Got home from work Monday night and the airlock was full of wort

What are you using for temperature control?

What yeast did you (re-)use?

 

[Carolina_Matt]

What are you using for temperature control?

What yeast did you (re-)use?

The yeast is Safale 05 - as basic as it gets.

In the summer I use a chest freezer hooked up to an inkbird. In the winter when my garage is too cold, I don't control temperature as much. It's typically in the 60-65 degree range downstairs in the winter, so I just let it ride. Whenever I've checked the temperature (the strip attached to the side of the fermentation bucket), it's been right around 62 degrees for the last few days.

I'd think the fermentation would take off like this if it was too hot, but I'm towards the low end of the temperature so, if anything, I figured it would be slower.

 

[Brooothru]

The yeast is Safale 05 - as basic as it gets.

In the summer I use a chest freezer hooked up to an inkbird. In the winter when my garage is too cold, I don't control temperature as much. It's typically in the 60-65 degree range downstairs in the winter, so I just let it ride. Whenever I've checked the temperature (the strip attached to the side of the fermentation bucket), it's been right around 62 degrees for the last few days.

I'd think the fermentation would take off like this if it was too hot, but I'm towards the low end of the temperature so, if anything, I figured it would be slower.

Keep in mind that the external surface temperature of your fermentation vessel is quite a bit less than the internal temperature at the core of your FV, especially at high krausen. My basement temperature this winter has been running at 64~66F, but for my last batch at Day 3 after the yeast pitch the internal temperature (measured inside a thermowell, stainless steel FV) peaked at 73F. When I transferred to a keg for krausening on Day 6, the measured temp was 64F. I'm no longer able to record the outside skin temperature of the FV because it's now wrapped with a Reflectix thermal blanket, but past examples have indicated near ambient temperatures at high krausen on the outside FV surface while the inside is significantly warmer.

Brooo Brother

 

[kh54s10]

I'd think the fermentation would take off like this if it was too hot, but I'm towards the low end of the temperature so, if anything, I figured it would be slower.

It was slower based on the lag time. If it was too warm it would have started much earlier.

Cool can make a fermentation less vigorous, but not always. How vigorous the fermentation, is what you are experiencing.