Dry your own yeast?

I was thinking I'd try to dry my own yeast. Why? Just because.

Anyone try this before?

1) Dehydrator. 2) 5% humidity. 3) Vacuum sealer (or evacuate sealed envelope with CO2).

I have a microscope, so I need to get a hemocytometer and I can count cells and figure viability.

If you manage to get one of the liquid strains to work, that would be something.

I assume you're talking about drying it to reuse it as yeast, not as a nutritional supplement? If so, you need to be aware that not all varieties will survive drying. That's why there are fewer dry yeast strains than liquid available. And what about maintaining sterility? I admire your creativity, but don't hold much hope of success.

How hot does a dehydrator get?

In that sacred herbal beers book, I forget the exact name, the author claims several cultures would either dip a stick or branch or something in the trub and hang that in their house somewhere. Then to get the next beer going, they'd use the stick with the dried yeast on it to stir the cooled wort and off it goes. I'm sure some of the yeast cells will survive, but enough to make the dried product viable, I'm not so sure.

Picobrew said:

How hot does a dehydrator get?

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No idea. Don't have one. Not sure how they work at all. I need to research this.

Denny said:

I assume you're talking about drying it to reuse it as yeast, not as a nutritional supplement? If so, you need to be aware that not all varieties will survive drying. That's why there are fewer dry yeast strains than liquid available.

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Yea, I wondered about that.

Denny said:

And what about maintaining sterility? I admire your creativity, but don't hold much hope of success.

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I fail a lot, but my successes are astounding!

If you're determined to try it, I'd recommend you do some research into the methods of commercial yeast producers. Like I said, as much as I admire your desire to do this, I think you're underestimating the ease with which it can be done.

passedpawn said:

No idea. Don't have one. Not sure how they work at all. I need to research this.

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Mine goes up to 135F.

I think dehydrators depend on both heat and airflow, two things which will cause problems. The airflow will not only bring in "bad things" but will also blow the yeast around (if it dries out).

Drying and rehydrating yeast would be tall challenge IMO. I would get some glycerine and freeze the little buggers. Not too difficult from what I've read...of course, YMMV.

wilserbrewer said:

Drying and rehydrating yeast would be tall challenge IMO. I would get some glycerine and freeze the little buggers. Not too difficult from what I've read...of course, YMMV.

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I have been doing this for quite a while. Works great. Still, dry would be better.

I think commercial dried yeast is freeze, not heat dried.

Probably a reason for that...

But let us know if ya come up with something!

I think a regular food dehydrator would get too hot. According to Alton Brown, they get too hot to even dry food without cooking them a little. I see the convenience of buying dry yeast, but not necessarily in saving it dried.

I think sterility will be the biggest issue. I'm not entirely sure of the process, but I think what ends up happening is that most of the yeast die. The whole mixture is put through some kind of extruder that makes tiny rods made up mostly of dead yeast and some dormant. The dead yeast acts as energy stores and nutrient when it is rehydrated. Also, the drying process is not very easy on yeast, which is why there aren't a lot of dry strains available.

I do not think you will have much luck. A Professor i worked with did his PhD in this, you need to freeze dry it and there are a couple other additives that make the ice crystals small so they don't break the cell walls.

A food dryer will just get too hot and cook everything.

Great. I love it when everyone says it can't be done.

passedpawn said:

Great. I love it when everyone says it can't be done.

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So why don't you do some research and present us with evidence to the contrary? You've received several pretty well reasoned answers and all you say is "if you tell me it can't be done, I'll do it". That doesn't make much sense to me. Tell us why you think it can be done.

Denny said:

So why don't you do some research and present us with evidence to the contrary? You've received several pretty well reasoned answers and all you say is "if you tell me it can't be done, I'll do it". That doesn't make much sense to me. Tell us why you think it can be done.

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Damn, dude, I'm working on it. I've been researching this to death. Oh, and I just thought of doing it yesterday. I'm trying to solicit some advice from a couple of yeast companies (I seriously doubt I'll get anything useful from them, but can't hurt to ask). I invent stuff for a living... this would be nothing.

Why do I think it can be done? It's been done before, so there is that.

Okey dokey, let us know how it goes. I hope you can make it happen.

My understanding (From memory, I'm paraphrasing what Chris White, of White Labs on one of the various Brewing Network shows said sometime in the last 12 months)

'White Labs doesn't produce dry yeast because we can't get the same purity in a dried yeast, that they can in a live yeast.' - White Labs

- (my commentary) So this indicates that one problem commercial producers have (that you may not be as concerned with) is uniformity of the strain, and low contamination.

'We are moving towards producing dry yeast as soon as we can have equivalent 'quality''. - White Labs

'Commercial level equipment will cost $1M.' - White Labs

- (My commentary) Taking the above in combination, You probably /Can/ succeed on a personal level to store some yeast in a dried form. By repurchasing liquid every so many generations you can probably avoid the contamination issue.

- If I was attempting this, I would use the goal of starting with a yeast cake, and generating lets say 4-5 'pitch-able' quantities of dry yeast I would plan on 25% viability for a first stab. This means I need 11 grams (per commercial packet)* 5 pitches * 4 (viability multiplier) = 220 grams of dry yeast 'substance' or about 10 oz. This seems doable.

- I'm thinking that because you are doing proof of concept, and not worried about "Long Term" strain viability that you might make Yeast Cheese or Fudge. Wash your yeast 3-4 times, then spread it out on a cheesecloth. Press and Dry manually over a day or so... keep the temps under 70. After a couple of days, cut your 'cheese' cake into fifths and then spread again manually on a paper plate. one paper plate per section. Cover with newspaper and let dry to completion. After drying finishes, scrape off your yeast, or simply put the entire paper plate in a plastic zip lock bag.

- I'm not saying it will be pretty, or even pretty useful, but I'm sure that you will have some viability.

Good Luck!

If you have access to some kind of vacuum manifold, you could spread the yeast thinly onto a surface and use the vacuum to dry it out without exposing it to heat or tons of air.

KevinWP said:

- I'm thinking that because you are doing proof of concept, and not worried about "Long Term" strain viability that you might make Yeast Cheese or Fudge. Wash your yeast 3-4 times, then spread it out on a cheesecloth. Press and Dry manually over a day or so... keep the temps under 70. After a couple of days, cut your 'cheese' cake into fifths and then spread again manually on a paper plate. one paper plate per section. Cover with newspaper and let dry to completion. After drying finishes, scrape off your yeast, or simply put the entire paper plate in a plastic zip lock bag.

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That sounds like it could work. That sounds similar to the yeast blocks commercial bakers use. It comes in a block that isn't as dry as instant yeast, or dry brewers yeast. It has to stay refrigerated and used quickly.

I am thinking about freeze-drying with added glyerine and/or ascorbic acid. Problem here is that I need to expose it to air. I'll experiment with an open container, open-cell foam airlock, etc. until I get a way to allow it to freeze and sublimate without contaminiation.

I don't have a good way to create any significant vacuum, although that is a very interesting idea.

Did you ever have success with this?

I think it can be done.
The commercial guys do it so I amend that to I know it can be done.

A food dehydrator is really just a concept. By the time you modify the heating element controls to produce lower or no heat and build on a HEPA intake filter and modify the shelves to suitably contain the yeast you would probably have been better off to have started from scratch than with a food dehydrator.

Freeze drying is a better idea but equipment costs are going to be prohibitive.
If you have the money you can just buy and install a freeze dryer made specifically for sterile work, like this: http://www.millrocktech.com/steam-sterilizable-production-freeze-dryers.html

LOL!

At any rate aseptic, functional packaging of the yeast prior to drying would be a fairly hard problem to solve without a clean room environment.

LeakyBucket said:

Did you ever have success with this?

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No, I'd still like to mess around with it, but I got wrapped up with a major upgrade to my whole system and lost interest in drying. Maybe later, maybe not.

Ah, oh well. I was hoping you had maybe ironed out a process.

http://www.sourdo.com/index.htm - Dr Ed Wood dries his Sourdough cultures and sells them. He is doing it on a small scale and it certainly works. Can't remember if he details it in his book but it can be done.

KingBrianI said:

In that sacred herbal beers book, I forget the exact name, the author claims several cultures would either dip a stick or branch or something in the trub and hang that in their house somewhere. Then to get the next beer going, they'd use the stick with the dried yeast on it to stir the cooled wort and off it goes. I'm sure some of the yeast cells will survive, but enough to make the dried product viable, I'm not so sure.

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I was going to point out the same thing. There is a precident for it. If it could be done in ancient times, then I'm sure with modern DIY creativity and basic sanitization why couldn't it?

I betcha even something simple as smearing yeast on a glass plate, putting it in some sanitized container and drying it even just with a light bulb suspended far beneath it so the heat rises could dry it out.

AND you only need a few viable cells to grow back later.

Aw crap, I hate when I fall for the ole zombie thread ressurection thing.

Revvy said:

Aw crap, I hate when I fall for the ole zombie thread ressurection thing.

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You prefer it when we just start up a million new threads to rehash the same topics? The OP did respond to this one, btw.

TheSeether said:

You prefer it when we just start up a million new threads to rehash the same topics? The OP did respond to this one, btw.

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No, I like THIS. I just usually don't fall for it, and just start posting in a resusatated thread as if it was brand new. I didn't look at the date of the OP's original post or noticed what was ressurected. Usually I realize it and if I am posting in a zombie thread, I'm posting in regards to the most recent comments, not the original ones.

passedpawn said:

I fail a lot, but my successes are astounding!

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I'm stealing that.

In regards to the stick of yeast eh?

Well, now that it's rez'd for a short time, I'd like to mention the possibility of using an aspirator (water aspirator perhaps) and a Buchner funnel?
*Edit: The funnel, filter disks and the chamber it sits on seems relatively inexpensive. Total about $50?)

To add to the zombies:

Dry Ice and rubbing alcohol will get you cold enough for the freeze part but I'm not sure if you can maintain the low pressure long enough with DIY HW to make this practical. Maybe a vacuum pump combined with a glass carboy and appropriate fittings would work. The seal at the top of the carboy would be interesting to see though.

Rise and shine zombie thread!

Any reason why noone has tried the old school method of a wood paddle or birch whisk? I would be willing to try this with a couple of small ale batches I think.

maltoftheearth said:

Rise and shine zombie thread!

Any reason why noone has tried the old school method of a wood paddle or birch whisk? I would be willing to try this with a couple of small ale batches I think.

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I do believe King Brian and I both mentioned it, not too many posts above this one.....It's even mentioned in Palmer-

There was a time when the role of yeast in brewing was unknown. In the days of the Vikings, each family had their own brewing stick that they used for stirring the wort. These brewing sticks were regarded as family heirlooms because it was the use of that stick that guaranteed that the beer would turn out right. Obviously, those sticks retained the family yeast culture....

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Michael Jackson mentions it as well, in THIS article.

Early beers were fermented by airborne wild yeasts. Norse legend says that Odin, disguised as an eagle, spilled the secret of beer from the sky. The Norwegian brewers learnt that, if they kept the stick they had stirred their previous brew with, it would help to start the next fermentation. Coated with sticky residue, the "magic sticks" harboured millions of living yeast cells. Later called "yeast logs," some have been kept as family heirlooms.

Today, in the rural valleys of the mountainous west, almost every farmer keeps a supply of liquid yeast for home-brewing, and all say that this precious resource has been in the family "for as long as we can remember, probably from Viking times." To explore this culture, I took the train from Bergen to the mountain town of Voss, where most visitors ski or fish for salmon.

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I wonder since Passedpawn now has a hemocytometer if he's going to try this. What say you PP?

I was thinking of trying this for a while but so far I haven't found a yeast I couldn't resurrect from liquid/cold storage. I'd want to try this to store for a very, very long time, like tens of years.

maltoftheearth said:

. . . .Any reason why noone has tried the old school method of a wood paddle or birch whisk? I would be willing to try this with a couple of small ale batches I think.

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The only problems I see with this is: You'd still have to store it dry AND dry it in a semi confined area to prevent contamination, then where do you store it to keep it from being contaminated/infected. I guess if it's not expected to be very long between brews it would be fine. Maybe I'm looking at dry storage the wrong way, I assumed it would be for long term? Still, our ancestors did it, so where did they store them? In the vat with the wort for the next brew? In the rafters of the brewhouse? I can't help but think each one would have some sort of bacterium? I suppose that is why antiseptic additions were added.

COLObrewer said:

I wonder since Passedpawn now has a hemocytometer if he's going to try this. What say you PP?

I was thinking of trying this for a while but so far I haven't found a yeast I couldn't resurrect from liquid/cold storage. I'd want to try this to store for a very, very long time, like tens of years.

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Funny you posted, I came across this passage in the Michael Jackson article on ancient Norwegian brewing techniques, and was going to pm you with this passage, and see what you thought about it...I think you should try this.

Michael Jackson said:

One morning, I climbed a hillside with another farmhouse brewer, Svein Rivenes. He showed me the stream where he had tied a sack of barley so that it would germinate -- a primitive form of malting.

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Revvy said:

Funny you posted, I came across this passage in the Michael Jackson article on ancient Norwegian brewing techniques, and was going to pm you with this passage, and see what you thought about it...I think you should try this.

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I'd like to try it! Unfortunately I'd have to travel a few miles to the nearest stream that I would consider "pure" enough, a canal runs through my property but it may or may not, at times, have chemicals/fertilizers/insecticides from upstream farmers tail water.

I seen an episode (I forget what venue) where an old time moonshiner dropped his gunny sack of corn in a stream to the same end.

Thanx for the link to MJ, I especially like this quote: . . . . . .The sisters were there. "Home-brew and sheep's head!" one of them exclaimed to me. "Without the home brew, you may as well leave the head on the sheep."

True enough I would suspect