Is there a way to propagate yeast at home and that way stop buying the sachets?

[Elysium82]

Hey guys,

The title gives it all away.

So, can we buy a sachet of yeast and then just reuse that yeast that we have at the end of the fermentation?

I assume the biggest issue might be creating the starters and possibly contaminating our wort.

I have read that some people use petri-dishes inoculate that agent (agar agar) and create the starter from that. Can anyone tell me more about that?

I am planning to do BIAB and all this might be too time-consuming, but I just thought I'd get informed a bit more and see if there are easy way of reutilising yeast from previous batches.

Thank you.
UPDATE: I have just found this video:


It looks like it is called yeast washing, but are there any issues that this method of harvesting yeast might cause? God knows...other things might get into the yeast...

 

[z-bob]

What yeast are you using? And what do you use for a fermenter? There are a few yeasts that you can just scoop the foam off the top of the fermenter on about day 2 or 3 and put it in a sanitized jar in the refrigerator. (this is called "top-cropping" and that should be mentioned in the yeast description.) That's my favorite method but it doesn't work with the yeasts I am using right now. It also wouldn't work if you're fermenting in a carboy because you'd be working thru the narrow neck.

Something that works with any yeast is just saving the sludge at the bottom of the fermenter. Pour it and some of the beer into several sanitized jars and refrigerate them. You don't need to wash it; the only reason I can think of why you would is to save refrigerator space (because you can use much smaller jars for the washed yeast)

And I guess you could build up a starter before you brew then only use half of it; save the other half for the next batch.

 

[Bassman2003]

Yes. Reusing yeast is what most every professional brewery out there has done for ages. It just takes some research to get familiar with the processes and chose the best way for your brewing.

 

[IslandLizard]

There are 2 different processes that are often mixed up (pun intended). Yeast washing uses an acid while yeast rinsing uses just water. The process illustrated in the video only uses water, so it's yeast rinsing, and thus titled incorrectly.

Yeast washing kills bacteria. Yeast rinsing helps remove trub and dead yeast (through sedimentation), but doesn't kill bacteria, they remain.

The best way to have the best, purest, uncontaminated most viable and vital yeast is by making starters from commercially produced yeast. Liquid (wet) as well as dry (dried) yeast made by yeast manufacturers is very clean, see their product specifications.

As soon as we use that yeast in a fermentation or starter it will become contaminated to some degree, progressively getting worse with every reuse. We just manage those contaminations so our yeast strain (or mixture of strains) keeps the upper hand.

 

[Elysium82]

There are 2 different processes that are often mixed up (pun intended). Yeast washing uses an acid while yeast rinsing uses just water. The process illustrated in the video, is yeast rinsing.

Yeast washing kills bacteria. Yeast rinsing helps remove trub and dead yeast (through sedimentation), but doesn't kill bacteria, they remain.

The best way to have the best, purest, uncontaminated most viable and vital yeast is by making starters from commercially produced yeast. Liquid (wet) as well as dry (dried) yeast made by yeast manufacturers is very clean, see their product specifications.

As soon as we use that yeast in a fermentation or starter it will become contaminated to some degree, progressively getting worse with every reuse. We just manage those contaminations so our yeast strain (or mixture of strains) keeps the upper hand.

Thank you. So, in a way yeast rinsing is the good and easy way to deal with this, right? Since we give the yeast the chance to keep the upper hand, right?

 

[mashpaddled]

Thank you. So, in a way yeast rinsing is the good and easy way to deal with this, right? Since we give the yeast the chance to keep the upper hand, right?

Rinsing is just using clean water and gravity to dilute trub and then let it settle out so you can separate out the grain and hop sediment. You're not going to get any bacteria or wild yeast out of the culture that way. Rinsing lets you eyeball how much yeast you have in the jar with some wildly inaccurate guesswork. If anything, it risks greater infection if you intend to keep the jar in the fridge for a while. Beer is a better protector of those yeast cells due to alpha acids and alcohol than water which has a higher ph and no antibacterial agents.

 

[Elysium82]

Rinsing is just using clean water and gravity to dilute trub and then let it settle out so you can separate out the grain and hop sediment. You're not going to get any bacteria or wild yeast out of the culture that way. Rinsing lets you eyeball how much yeast you have in the jar with some wildly inaccurate guesswork. If anything, it risks greater infection if you intend to keep the jar in the fridge for a while. Beer is a better protector of those yeast cells due to alpha acids and alcohol than water which has a higher ph and no antibacterial agents.

ok. Then the only safe option is the one described here: Yeast Washing & Yeast Rinsing: What's the Difference?

Food-grade phosphoric acid?
but then pH measurement is necessary too. Hm....

 

[mashpaddled]

ok. Then the only safe option is the one described here: Yeast Washing & Yeast Rinsing: What's the Difference?

Food-grade phosphoric acid?
but then pH measurement is necessary too. Hm....

You can just keep the trub together with the beer that came with it. If you practice good sanitation practices, you shouldn't have that much of a problem with infections. This is fine if you intend to repitch serially.

If you want to maintain a more permanent culture you can follow a very similar process. When I buy a new strain I pull some of the sachet out to a separate starter that I keep as a mother culture in a mason jar in the fridge. I feed it occasionally and when I need that strain I propagate out of it. That keeps a clean culture without worrying about picking up any low level infections from trub or equipment.

 

[marc1]

When I make a starter for a batch of beer, when it's done I pour some off into a sanized Mason jar and keep it in the fridge. The next time I need the yeast, I use that to make the next starter, and then save some if that one, and so on.

 

[Kickass]

I currently have 5 different yeast strains in my kegerator. Nothing fancy, just practice thorough sanitation and store in mason jars.

 

[DBhomebrew]

When I make a starter for a batch of beer, when it's done I pour some off into a sanized Mason jar and keep it in the fridge. The next time I need the yeast, I use that to make the next starter, and then save some if that one, and so on.

That's my practice as well. I used to harvest some of the finished beer's cake, but I find overbuilding the starter gives better results with very fresh and clean yeast going into the fridge.

 

[Bassman2003]

I just posted a video about the yeast freezing process. This is the method I am using as it allows me to brew with different yeasts beer to beer instead of re-using the same yeast in a timely fashion before it dies off.

 

[Elysium82]

I just posted a video about the yeast freezing process. This is the method I am using as it allows me to brew with different yeasts beer to beer instead of re-using the same yeast in a timely fashion before it dies off.

Hey. Nice video. Thanks.
Let me see if I get this: you use liquid yeast, divide it into 4 vials, and then use one of the vials in order to make a 2L starter...and you start the process all over again? Instead of a store-bought yeast pack...you just use that 2L starter, right? Unlimited power?

Thank you.

 

[McMullan]

Freezing yeast is more about long-term storage of back-up samples. It is not a substitute for repitching healthy fresh yeast. For medium-term storage, 6-12 months, I'd recommend yeast slopes/slants stored in a fridge. A meaningful comparison, e.g., a viability test and QC on agar plates, explains why. Freezing using home-brew protocols is an effective way to promote yeast stress, mutation and genetic drift. Just keep that in mind if the aim is to bank a collection of different yeast strains.

 

[Bassman2003]

Hey. Nice video. Thanks.
Let me see if I get this: you use liquid yeast, divide it into 4 vials, and then use one of the vials in order to make a 2L starter...and you start the process all over again? Instead of a store-bought yeast pack...you just use that 2L starter, right? Unlimited power?

Thank you.

Yes. The thinking is that you grow up fresh yeast and use it per vial. The yeast created has a lot more vitality than buying it from the homebrew shop. The yeast shown in the video was for a Belgian blonde 5 gallon batch. The yeast tore through the batch. If I was brewing a lager I would take two vials out and grow them up concurrently.

Yes, you can chose to take the slurry from one batch and freeze 4 more vials and the loop the thing for ages as long as you brew clean.

 

[Bassman2003]

Freezing yeast is more about long-term storage of back-up samples. It is not a substitute for repitching healthy fresh yeast. For medium-term storage, 6-12 months, I'd recommend yeast slopes/slants stored in a fridge. A meaningful comparison, e.g., a viability test and QC on agar plates, explains why. Freezing using home-brew protocols is an effective way to promote yeast stress, mutation and genetic drift. Just keep that in mind if the aim is to bank a collection of different yeast strains.

It is always about compromises. I tried re-pitching but found my brewing was too varied to keep the yeast healthy and alive. Once I make a lager, I often want to make an ale for the next batch etc... Two weeks is maximum before you start to lose the refrigerated slurry from a batch. The lager yeast would die off by the time I used it again... So freezing is a way for me to have better yeast vitality in the end because most of what you pitch is freshly grown imho. Even compared to store bought wet yeast as that stuff often is 1-2 months old. The yeast brand I use in the video is a smaller outfit. The direct turnaround is better than the store option which passes hands before retail. One can grow up more store bought yeast for sure but this method is cheaper in the end and easier in some ways.

 

[McMullan]

Sure, not everyone has time to brew frequently enough to get the benefits from repitching fresh healthy yeast for free without making a starter. If you believe your method is the best compromise for you that's all that matters to you. For me, when I haven't got yeast to repitch and have to start over, it's a loop of yeast from a slope and a 10ml mini culture stepped up to a healthy pitching rate.

 

[z-bob]

Sure, not everyone has time to brew frequently enough to get the benefits from repitching fresh healthy yeast for free without making a starter. If you believe your method is the best compromise for you that's all that matters to you. For me, when I haven't got yeast to repitch and have to start over, it's a loop of yeast from a slope and a 10ml mini culture stepped up to a healthy pitching rate.

Any videos on how to make and maintain the slants? I don't brew often enough to repitch healthy cultures very often, I usually rely on overpitching a tired culture; hopefully strains that are okay with that (like kveik yeasts)

I should also freeze a few backup vials.

 

[hottpeper13]

After taking a microbiology for brewers course thru UWM I got lab gear and bought the 30 qt American pressure caner as an autoclave. I plated all my yeasts and they only lasted 6 mos. I've had yeast with beer on top last 3 yrs in the fridge. I cycle my house yeast 2-3 times a year, and repitch those at least once. The others cycle ~ 1-2 times a yr.
If my Saison yeast mutated in the 3 yrs, doesn't really mater because I'm diggen'it.

 

[McMullan]

@z-bob, there's no shortage of info re maintenance of yeast on slants. Search the forum. I'm sure you'll find what you're looking for.

@hottpeper13, yes, some people seem to have less success with yeast slants. Difficult to say why. As a well-established standard procedure known to work well presumably deviations from the instructions, poor instructions or just random bad luck with poor quality ingredients. I suspect some people use too much agar and end up with a very firm matrix that nutrients struggle to diffuse through, for example.

 

[Bassman2003]

No doubt there are a lot of different angles for yeast handling. Any way you choose, the goal is a lot of fresh yeast cells with a running start to pitch in your batch. I am trying to keep all three of these in the positive column these days and not stray. This method gives me a process that I can easily repeat and get to the end goal.

 

[JAReeves]

You may want to try a few of these processes and see which one works best for your time and space.

I started out collecting trub from the bottom of the fermenter and pitching a jar into the next batch. The dead yeast acted as yeast nutrient for the next batch, so fermentation was usually a pretty fast start. Once I had more room to store brewing stuff, I moved to making a starter, then saving part of it to make the next and so on. It requires the making a starter in advance of brewday, so an extra step. I think the quality is better, but it takes more time and planning to make work. Find the process that works for you, and no matter what make sure your sanitation in on point.

 

[Reneauj62]

Hey guys,

The title gives it all away.

So, can we buy a sachet of yeast and then just reuse that yeast that we have at the end of the fermentation?

I assume the biggest issue might be creating the starters and possibly contaminating our wort.

I have read that some people use petri-dishes inoculate that agent (agar agar) and create the starter from that. Can anyone tell me more about that?

I am planning to do BIAB and all this might be too time-consuming, but I just thought I'd get informed a bit more and see if there are easy way of reutilising yeast from previous batches.

Thank you.
UPDATE: I have just found this video:


It looks like it is called yeast washing, but are there any issues that this method of harvesting yeast might cause? God knows...other things might get into the yeast...

I washed my yeast once... that was enough for me. I have found that overbuilding your yeast is so much better. It is faster, less effort, less cleanup, and practically zero chance of contamination. Also, your yeast won't pick up any flavors (off flavors) from your previous brews.... so, if you brewed a dark beer with heavy flavors, it won't show up in your light pilsner...

 

[beren]

This works great! Maintaining A Healthy Yeast Bank Long Term

I just pulled my 2nd vial of Irish Ale out. 12h had ok activity in the stir plate but 24h it was cooking.

I use glass vials so I can reuse them. About the same price as plastic but be careful to not break them. If you want to do extra each batch you can make a 2l starter and get 20 vials at once. If you want a 2l starter just use 1 vial and 1l, after 24h or so add another liter of starter wort

 

[bwible]

In theory its possible to keep the same yeast going indefinitely if you brew often enough. The problem is most of us don’t brew every couple weeks. Some breweries, especially in Germany or Belgium, have been using the same yeast for more than 100 years. Now thats not to say they also don’t have labs where they clean and treat the yeast.

I always try to re-use my yeast a few times when I get a pack. Like I said, the issues we run into are not being able to brew often enough and contamination/infection, and also carryover flavors from batch to batch. If you brewed a stout, for example, you wouldn’t want to put a blonde ale on top of that yeast cake. I never got into yeast washing.

I finally got my hands on a limited release Wyeast pack earlier this year that I had been waiting years for. I brewed with it and tried to save it by freezing with glycerine per this article:

https://www.homebrewtalk.com/threads/maintaining-a-healthy-yeast-bank-long-term.678997/
After about 3 months I took out one of the vials and made a starter. This is supposed to be clean American lager yeast. The starter went off and was all phenolics. When I tasted the starter which was just made with some light DME it tasted like a German Wheat beer. More clove flavor than band aid. But clearly not clean.

I discarded that starter and proceeded to try again with the same results. I made 8 vials out of the yeast when I tried freezing it. I made starters with 4, and all were off. I’m not sure where I went off in the process of collecting and freezing the yeast. I sanitized everything and even wiped my work surface with clorox wipes. One thing I can think is I collected yeast from the secondary and not the primary. The resulting beer is a pre-pro lager that I still have some left on tap and its clean.

I’m disappointed because i can’t get this yeast again and I really wanted to use it. I have one more smack pack I can work with and try again. After that I can’t get it again until Wyeast decides to release it again.

I don’t have a problem with buying yeast and getting a few uses out of it. But it would be nice to be able to save yeast long term, if just to be able to keep the special ones you can’t get. Long term to me would be 6-8 months. I’m not going to get into slanting, especially if I can’t do the freeze method without contamination.

 

[beren]

Ah I collected my yeast straight from the pack. Make an oversized starter, took 1l and decanted, split into 10 vials. The other 1l went into the beer

 

[bwible]

I washed my yeast once... that was enough for me. I have found that overbuilding your yeast is so much better. It is faster, less effort, less cleanup, and practically zero chance of contamination. Also, your yeast won't pick up any flavors (off flavors) from your previous brews.... so, if you brewed a dark beer with heavy flavors, it won't show up in your light pilsner...

This is great. Thanks

 

[Bassman2003]

I plan on mainly only freezing yeast straight from the package. So if I buy a pack, I can freeze four vials. That is four ale batches or two lagers. Still good value. I will try some freezing from harvested yeast with common strains like Chico and see how it goes. But I am realistic that homebrew sanitation leaves a lot to be desired when it comes to lab yeast practices.

 

[hottpeper13]

Well @McMullan, the reason I stated the class and the autoclave is that everything was done under lab conditions with the exception of the Hood. So I used a map gas torch. The left over agar is over 5 -7 years old and still looks the same. The pucks in the fridge had mold in 6 months, never tried freezing slants because doing a 3 step starter is a pain and my saved overbuilds ,so far have been successful.

 

[mashpaddled]

I don’t have a problem with buying yeast and getting a few uses out of it. But it would be nice to be able to save yeast long term, if just to be able to keep the special ones you can’t get. Long term to me would be 6-8 months. I’m not going to get into slanting, especially if I can’t do the freeze method without contamination.

Of the several yeast strains hanging out in jars in the back of my fridge, many of them might only get used once in a beer, fed 3-4 times per year, and some are at least four years old. No problems, not seeing weird mutations or infections. If you wanted to save a huge number of strains, freezing is more manageable just for size and not needing to worry about feeding yeast every few months. If you can handle the upkeep of a few mason jars and have the space, it's such an easier option.

 

[IslandLizard]

One thing I can think is I collected yeast from the secondary and not the primary.

That practice of collecting from a secondary is generally discouraged. There's a good chance the secondary doesn't contain the same population as the original yeast (starter). The more flocculent population has settled out in the primary, while the less flocculent ones get transferred to the secondary.

I’m disappointed because i can’t get this yeast again and I really wanted to use it. I have one more smack pack I can work with and try again.

I'd build up a good size starter, freeze some and save some as slurries in the fridge in small 4 oz jelly jars for starters later on.
For example, I'm still using yeast I bought in 2015 (a few even older), many were partially used, still in the original (East Coast Yeast) bottles they came in. So far, they've had no problems resurrecting themselves.

Which yeast strain is it?
Yes, many of us are wishing for more frequent WYeast "seasonal" re-issues. I've missed a few I wanted and they've never reappeared. Not much one can do than moving on, and keeping an eye out. Similar for White Labs' yeast vault...

 

[McMullan]

Well @McMullan, the reason I stated the class and the autoclave is that everything was done under lab conditions with the exception of the Hood. So I used a map gas torch. The left over agar is over 5 -7 years old and still looks the same. The pucks in the fridge had mold in 6 months, never tried freezing slants because doing a 3 step starter is a pain and my saved overbuilds ,so far have been successful.

And the reason I've stated what I have is I spent more than a course in molecular biology, including over 3 years demonstrating practicals to undergraduates and postgraduates, followed by over 10 years managing commercial labs and providing training. I'm aware that even under laboratory conditions people sometimes get things wrong. So, if you ever decide to give it another go, feel free to ask for help. I'm sure it'll improve your chances of successfully maintaining yeast on agar

 

[beren]

I plan on mainly only freezing yeast straight from the package. So if I buy a pack, I can freeze four vials. That is four ale batches or two lagers. Still good value. I will try some freezing from harvested yeast with common strains like Chico and see how it goes. But I am realistic that homebrew sanitation leaves a lot to be desired when it comes to lab yeast practices.

Make a 1-2l starter and make 10-20 vials. Each vial is 1/10 yeast of a liter starter. Pitch 10:1 and zoom.

 

[Gilbert Spinning Horse]

No one has mentioned Kveik yet. The slurry left after the ferment with Norwegian farmhouse yeasts (Kveik) can simply be poured onto a sheet of silicon paper and left to dry. Scrunch up the paper and collect the flakes and you have enough yeast for the next 100 brews. It can be stored in the fridge and will keep for years. No need to make a starter with Kveik, just sprinkle 1 gram of dry flakes on the top and watch it rip through the wort.

 

[DuncB]

No one has mentioned Kveik yet. The slurry left after the ferment with Norwegian farmhouse yeasts (Kveik) can simply be poured onto a sheet of silicon paper and left to dry. Scrunch up the paper and collect the flakes and you have enough yeast for the next 100 brews. It can be stored in the fridge and will keep for years. No need to make a starter with Kveik, just sprinkle 1 gram of dry flakes on the top and watch it rip through the wort.

I dried mine on greaseproof paper and keep the flakes in the freezer. Just take the box out of the freezer and grab some flakes sprinkled on the top of the wort and stir them in if you want. Then as you say sit back and watch it go crazy.

 

[wepeeler]

When I make a starter for a batch of beer, when it's done I pour some off into a sanized Mason jar and keep it in the fridge. The next time I need the yeast, I use that to make the next starter, and then save some if that one, and so on.

This is exactly what I do. I've used 1 smack pack and harvested out about 5-7 generations. Just use this calculator, and it'll give you a good idea on how much DME to use to build up a starter.

 

[McMullan]

No one has mentioned Kveik yet.

There's a very good reason for that. It makes beer taste a bit funny, what I'd call crap, unless used in hop bombs, where the intense hoppy flavour masks the unrefined funniness. But, yes, drying might be an easy option for some home brewers. Yeast usually survive being dried on filter paper. Good aseptic technique and sterilised filter paper are highly recommended. Work under a suitable flame (a Bunsen or similar) in a draft-free zone. Seal from air then store in the fridge or freezer. If stored in a bucket hung up in a barn for decades it's going to end up turning a little bit funny, like kveik, of course.

 

[Gilbert Spinning Horse]

There's a very good reason for that. It makes beer taste a bit funny, what I'd call crap,

That's your opinion mate.
Personally, I've had great results with some strains, not so good with others.
Maybe you were doing something wrong when you tried it out or maybe you don't have much experience with it.

 

[McMullan]

That's your opinion mate.

Yes, it is my opinion. And an opinion expressed by quite a few home brewers, in reality. For most beers there are much much better yeast strains available to home brewers. Most home brewers accept this, because it's true. The 'unique qualities' of kveik are mainly just marketing speil. What they most likely are really is semi-domesticated distiller's yeast adapted to ferment rendered spuds to produce washes for Norwegian potato whiskey. Do a little research on it. It's quite interesting. Norway's distilling history, at least over the last 200 years or so, absolutely dwarfs its brewing history into obscurity. Norwegian aquavit is one of my favourite spirits. In fact, gin and aquavit are about the only two spirits I drink. Anyway, what you decide to pitch into your worts is entirely up to you. Don't let me stop you.

 

[Gilbert Spinning Horse]

Yes, it is my opinion. And an opinion expressed by quite a few home brewers, in reality. For most beers there are much much better yeast strains available to home brewers. Most home brewers accept this, because it's true.

That's a typical bandwagon fallacy - because other people think that way it must be true.
Not that there's any proof that 'most' home brewers accept this either.
It's your personal opinion, and you're entitled to that, but you can't extrapolate that to be a general truth.