Guide to Making a Frozen Yeast Bank

Yakima 728
Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Originally posted by Gargoyle88:
Can the yeast from a secondary fermenter be used to start a yeast bank?
Click to expand...

I have done so with a pale ale and the next beer that I made with the yeast recovered from the secondary turned out fine.
 
Let's say I have a White Labs vial that is nearing or just past the "Best By" date. If I know I'm not going to be able to use it for a while, can I add glycerin to the vial and freeze it or would I be better off making a starter and then using that use to fill several smaller vials for freezing?
 
I'd say make a starter for it and then split it. Mainly just to check that it's still viable. And also you'd end up with up to about 10 times the amount of yeast after stepping up the frozen vials.
 
ok, i'm about to do this. quick question. i'm going to be sanitizing my plastic vials in starsan, not boiling them or anything. is the glycerin already sanitary? or should i pour out a mixture of the glycerin, and water, and boil them together before i add them to the vials, or just boil plain water, then add the unboiled glycerin, or what?

thanks. :)

brian
 
Just banked my first yeast this morning. :ban:

I'm gonna leave them in the fridge a few days then put them in the freezer. A few weeks from now I'm going to make a starter with one of them to make sure everything is working correctly. If all goes well my days of buying yeast are soon to be over. :)

Why isn't this a sticky? Would make it much easier to find.
 
I think boiling the glycerin/water mixture is a good idea. The boiling point of glycerin is over 500 degrees so it shouldn't boil off or change properties. I'll do that with my next harvest (London ale yeast). I also have some irish ale yeast that needs to be recultured as it is about 9 months old. I don't have a recipe for it so I suppose I'll just make a starter to re-culture.
 
The problem with this hobby, is that there is too much thinking involved to work up even a good buzz. You just can't wash or freeze yeast if your $hi* faced...

I know there is a way to enjoy both aspects of this hobby, but NOT until you quit doing/trying/making/learning/tinkering/experimenting/reading new things. At some point you just have to stop logging in to HBT. You kid yourself into saying you're just going to answer some poor noob's questions. But you're not fooling anyone. (by the way, I'm certainly not referring to myself here...) Of course, we all know that it's absolutely NOT about saving money or time.

When I started this hobby, I expected to see three toothed inbreds living in outhouses. What I ultimately found though is an amazing hodgepodge of highly motivated scientists, mechanical/computer/chemical engineers, chemists, professors and all around great guys.

If I wasn't so damn busy trying to build a wort chiller and stir plate, modify my freezer thermostat, wash & freeze some yeast all while trying to keep my wife from divorcing me.... I'd raise my glass to you all. :mug:

I've realized that this is a lifestyle, not a hobby and I LOVE every part of it, it's just that I've had 4 mondays this week and just need to RDWAHACHB (RDWAH a case of HB).


sorry for hijacking...:off:
 
conpewter said:
For vials on the cheap, go to your local wal-mart or other photo processing store and ask for 35mm film canisters (usually the little black jars, gray lids). They seem to be somewhere around 40 ML, I sanitize them in star-san for a while (I actually keep them full of star-san when not in use).
Click to expand...


I've got a bit of concern over using used film canisters. Film has some nasty heavy metals that I've no idea or confidence star-san will totally get out. You could be risking contamination at best and poison at worst. Why risk it.
 
That's a good point, probably best to not use them, it is not all that expensive to buy some vials to use (and then you can autoclave/pressure cook them) I was able to get a company to send me samples of their vials (plastic) but they only sent two :(

Edit:

Found an article concerning this. I'll continue to use them for my yeast storage, but I don't encourage anyone else to do so since they are not FDA approved (but apparently perfectly safe)

Urban Myth: Plastic Film Containers Contain "Toxic" Residues
Over the years, Kodak has received numerous inquiries about the safety of using 35 mm plastic film containers for purposes other than storing film. Some reported novel uses for the containers include salt and pepper shakers, storage of vitamins/pills, and as children's building blocks.

Because their purpose is to store film, the containers are not subject to Food and Drug Administration (FDA) requirements for materials that contact food or drugs nor Consumer Product Safety Commission (CPSC) requirements for toys marketed to young children. Therefore, we can't recommend the use of film containers to store food, spices, vitamins,etc. However, we have manufactured hundreds of millions of containers for many years without, to our knowledge, a single health-related complaint. To protect the film from contamination, Kodak quality standards require that the insides of the containers must be exceptionally clean. No "toxic" materials leach out or offgas from the containers themselves.

The black film containers are constructed of virgin high density polyethylene (HDPE) plastic, a tough semi-rigid material commonly used for kitchen utensils, tools, toys, and numerous other applications. The gray container lid is made of low density polyethylene (LDPE), also a commonly used plastic. Note: Young children should not be allowed to play with the cap since it may represent a choking hazard.

Newspaper and magazine articles have mentioned "toxic residues" in the containers which might come from the film. There are none. The chemicals in a roll of film are embedded in the gelatin emulsion layers (about as thick as a human hair) and do not rub off the plastic film base. The gelatin used in film is more highly refined than that used in common gelatin-based desserts.

The film base is triacetate plastic. Periodically, Kodak receives calls from customers concerned because their child or pet chewed on, or fully ingested, a quantity of film. From the viewpoint of the toxicologist, the concern is not one of toxic poisoning, but rather of mechanical injury, such as laceration of the esophagus, stomach, or intestines from the sharp edges of the film. Chemicals in the film are in such low concentrations that the risk of an adverse health effect is much too low to accurately predict.

In summary: There are no "toxic residues" in Kodak film containers. Because our film containers are not manufactured to comply with FDA or CPSC requirements, Kodak cannot recommend the use of film containers for anything other than their intended manufactured purpose. However, if a customer chooses to use a Kodak film container for other than film storage, the container first should be thoroughly washed with soap and water. To eliminate the potential for choking or mechanical injury, film containers, film lids, and film cartridges should be kept away from small children and pets.
Deborah Stein, Technical Information Specialist
Kodak Environmental Services
Eastman Kodak Company
Click to expand...

http://www.make-stuff.com/recycling/film_cannisters.html
 
Question: I have used this method with 50Ml Flat bottom screw top vials that were sanitized. I have 5 vials in the freezer now and I took one out today. Is the liquid in the vials supposed to be frozen or not. They look not totally frozen but partially to me. Is this right?
 
i have some trub on bottom of my starter, which I put in the fridge yesterday. should I rather freeze the liquid with suspended yeasts? or the yeast that has fallen out of suspension (with the trub)?

I thought that i should stir the starter wait for a hour or so, and decant the liquid and then let the yeast to suspend?

what do you think?

EDIT: I've just found Yeast Washing Guide, will do that first: https://www.homebrewtalk.com/f13/yeast-washing-illustrated-41768/
 
I just froze a few vials of the yeast I harvested here using dry ice. Is 12.2F (11C) cold enough to keep these vials frozen?

Edit: Using a modified Styrofoam cooler and ice in the freezer, it looks like the inside temperature where the vials are is right at 0F. I don't know how much this will rise during defrost cycles though.
 
Sounds like overkill to me. Just put them inside a thermal container like a lunch cooler so they will stay <32°F during defrost,
 
Better safe than sorry I suppose. :cross:

Plus the cooler has enough room for all the additional vials I have (56). I'm going to try keeping 4 vials of each yeast strain I come across.
 
I use 9 Ml tubes and pitch into 400 Ml wort and then step up to 2 liter. No problems on several types of yeast. BTW, I also pitched one tube well over a year old with no problems.

My methodology has changed some due to reading a thread on another forum that was a discussion between two microbiologist that are also homebrewers. Example below:
One of the major changes I have made in methodology has come because of postings from a fermentation microbiologist and a couple of referenced papers in that thread. Examples are given below. Homebrew is a screen name, not his real name for privacy reasons.

Homebrew wrote:
&#8220;Aliquots of liquid culture + 10% glycerol are quick-chilled in an alcohol/ ice bath and stored in a household freezer&#8221;
(Definition: In chemistry, an aliquot is usually a portion of a total amount of a solution.)
Further in that thread the reasoning for quick chilling and freezing is explained. Also this is one of the reasons I use small, 9ml culture tubes to expedite the freezing process. In addition, the use of 10% glycerol instead of the 15-25% given in other write-ups. This means you can get a greater % of yeast in a smaller tube.


Homebrew wrote:
&#8220;It is most important to quickly thaw to the point were ice crystals are gone (without swirling or shaking!). After that you can either pitch immediately or let it adjust to your wort temp...You would probably have a higher survival rate, less stress and a shorter lag if you warm to pitching temps. However you have to weigh that against the fact that the thawed cells are rather stressed and swimming around in spent medium+glycerol which is not very healthy. If you warm it up close to your wort temp (within ~5F) as quick as possible and then pitch, you should be fine.&#8221;
This is much shorter time from thaw to pitch than I had read before and the reasoning is given.

Homebrew wrote:
&#8220;Sterility-wise, I am not as anal with my working seeds and scale-ups as I am my master stock. If the master stock is contaminated, EVERY working seed/ fermentation made from it will be shot.&#8221;
The first time I froze yeast, I just washed the yeast from the primary of the strain I wished to harvest. Since it is more subject to contamination than the original pack, I now make my master stock from fresh tubes or packs I have purchased. While some may now see it as that critical, it is just another way I can insure a good master stock.
Click to expand...
 
Anyone found a cheap source of vials? I saw cynmar.com listed above but don't like the $25 minimum order.

How about the pipette? I can't seem to find the right thing. Thanks for any help.
 
Can the vials with the glycerin and water be "autoclaved" and saved until the yeast is ready to use or must they be autoclaved the same day as the yeast is harvested? The vials I purchased are autoclavable but I want to be sure they remain sterile for a couple of weeks while I make starters for my favorite strains.
 
Absolutely you could autoclave them and keep them on hand until you are ready to use them. The only thing to be careful about is exposing the contents to nasties when you open the vials. Lots of stuff can eventually get in between the neck of the vial and the cap.

I suggest getting a brand new zip-loc bag, and as soon as the vials are autoclaved, seal them up until you are ready to use them.

If you were really cautious, you might spray the vials (especially where the neck and cap meet), or flame the mouth of the vial before adding the yeast.
 
I assume there'd be no problem with pulling yeast straight from the WL or WY packaging and then into the glycerin vials? Besides the fact that you'd only get a few vials...
 
I'm about to set up my yeat bank and thought I would share this find. SWMBO is a science teacher and I was flipping through a supplies catalogue to find this:

Glass Separatory Funnel &#8211; 500 ml ~ Funnels

$24 bucks isn't bad. Since it is only 500mL, I plan on using a 1-2 quart starter, then crash cooling and decanting off the majority of the beer. Shake the starter to get the yeast back into suspension (so as to get as much as possible out), then the yeast slurry goes into the 500mL funnel and back into the fridge to settle out.

We'll see how it works!
 
goatchze said:
I'm about to set up my yeat bank and thought I would share this find. SWMBO is a science teacher and I was flipping through a supplies catalogue to find this:

Glass Separatory Funnel – 500 ml ~ Funnels

$24 bucks isn't bad. Since it is only 500mL, I plan on using a 1-2 quart starter, then crash cooling and decanting off the majority of the beer. Shake the starter to get the yeast back into suspension (so as to get as much as possible out), then the yeast slurry goes into the 500mL funnel and back into the fridge to settle out.

We'll see how it works!
Click to expand...

It is a great tool, and they are 1000 and 2000 ml too.
I didn't buy it, because it is large, bulky and fragile, it is dificoult to sterilize it and you have to hang it up somehow... another bulky equipement
 
The Mr. Malty calculator uses units of packages Wyeast or vials of WL as a unit.
Is there a rule of thumb for how to use the Mr. Malty calculator for the 20 mL vials? I guess what I am asking is: how many mL of starter do I need to be a equivalent to a package of yeast?
 
noisy123 said:
The Mr. Malty calculator uses units of packages Wyeast or vials of WL as a unit.
Is there a rule of thumb for how to use the Mr. Malty calculator for the 20 mL vials? I guess what I am asking is: how many mL of starter do I need to be a equivalent to a package of yeast?
Click to expand...

You're going to have to grow up that starter incrementally to get the most cells out of the 20mL as possible. I'd do something like 100ml ---> 500ml ---->1000ml. You're looking for a doubling of cells with each step-up.
 
flyangler18 said:
You're going to have to grow up that starter incrementally to get the most cells out of the 20mL as possible. I'd do something like 100ml ---> 500ml ---->1000ml. You're looking for a doubling of cells with each step-up.
Click to expand...

Would 1000 mL be sufficient for a typical mid-gravity beer (1.055)?
 
noisy123 said:
Would 1000 mL be sufficient for a typical mid-gravity beer (1.055)?
Click to expand...

I was just tinkering with the Mr. Malty calculator to see if this makes sense, so here goes:

I adjusted the slider to be thick yeast (4.5 billion cells/mL) and a 0% non-yeast component in the same. According to the calculator for an OG of 1.055, you'll need 469mL of starter to properly innoculate the wort. That being said, looks like a 500mL starter will do the trick. Of course, you need to figure out how much slurry you put into the 20mL vial to calculate the theoretical number of cells in your sample. Make sense? I think I've confused myself. ;)

Ostensibly, there is 0% loss in viability because the yeast cells are sleeping while frozen.
 
I agree with what you have above. I think Mr. Malty is not particularly good at scaling up from a very small amount of yeast. (Perhaps there is a linearization in the exponential growth model or something like that).

That said, I think what I will do is just have a look at what settles out in the 1 L starter and try and estimate the slurry properties from there. So far I have around 800 mL and roughly 100-200 mL of slurry (but I would probably want to refrigerate it to see how much more precipitates).
 
I pitch a 20 ml vial into 1 liter of wort on a stirplate

I write about it a little here
https://www.homebrewtalk.com/f13/aging-beer-facts-myths-discussion-84005/index3.html#post1082404

here is the article, and snipped text
Close examination of Figure 3 indicates that yeast should not be diluted more than 200 times the previous volume. In otherwords 10 ml should not be stepped up to more than 2 liters. The rationale behind this is simple. During yeast propagation it is important to keep the yeast growing exponentially (Figure 3, phase III). Diluting the yeast out too far will slow down their growth and give bacteria a chance to overtake the culture.
Click to expand...
MB Raines, Ph.D. - Guide to Yeast Culturing for Homebrewers - Maltose Falcons Home Brewing Society (Los Angeles Homebrewing)
 
Thanks, OP! I got my vials and glycerine ready, and will start my frozen yeast bank when I make my next starter.
 
noisy123 said:
The Mr. Malty calculator uses units of packages Wyeast or vials of WL as a unit.
Is there a rule of thumb for how to use the Mr. Malty calculator for the 20 mL vials? I guess what I am asking is: how many mL of starter do I need to be a equivalent to a package of yeast?
Click to expand...

I've been wondering about this quite a bit lately too. Do we have a solid answer yet? Or is it all a trial and error, guestimate type thing?
 
denimglen said:
I've been wondering about this quite a bit lately too. Do we have a solid answer yet? Or is it all a trial and error, guestimate type thing?
Click to expand...

After letting the yeast settle out of the beer in my flask, I have been using the "Repitching from Slurry" option (using the Thick Yeast weighting) to determine if my cell number is sufficient.
 
Cheers, I assume you're decanting off to another container to measure with?

Do you change the trub/slurry thickness sliders?

Usually I'm not too fussy, just pitch into a 300mL starter and assume that's the equivalent of a WY/WL pack, but just done the same with 1968, and it's settled out in the fridge and there's hardly anything there, but that yeast floccs up like a biatch.
 
Thanks in advance for the response and for the techniques listed!

So, I have propagated my first batch for freezing- Wyeast Saison.

After decanting and crash cooling I filled my 16ml vials with glycerine and yeast. After letting the vials sit in the fridge overnight it appears that they are 1/4 full with slurry. The wort etc seperated again.

Will this lead to failure?

Did I not do a good enough job seperating the wort from the slurry, or is this amount to be expected?

Thanks!!
 

Similar threads

Jhedrick83
Starting a small yeast bank
Replies
21
Views
3K
jtgoral
J
Cannonball Jones
Traditional Amis method of making jiuniang/酒釀/boozy rice.
Replies
0
Views
531
Cannonball Jones
Cannonball Jones
MBuckBrewer
Have Apples Make Cider!
Replies
1
Views
465
MaxStout
MaxStout
rtstrider
Building Frozen yeast bank straight from Pure Pitch/Yeast vendor pouch
Replies
4
Views
1K
Dynachrome
Dynachrome
Brooothru
Is Imperial L26 "Pilgrimage" blended yeast an Andechs strain?
Replies
31
Views
4K
Brooothru
Brooothru
CornyKegs 300

Latest posts

Back
Top