Prolonged Yeast Storage

[digdan]

k, I found the perfect yeast strain for my preferances. Now I need to know how I can keep a "mother crop" indefinitely, without spoiling or dying. I've heard to top the container off with vegatable oil to prevent oxygen while at near freezing temps. Anyone else have some good advise? ohh yea, the strain is WLP007

 

[david_42]

I haven't tried it, but long-term yeast storage is discussed in detail. This is an alternative to agar slants.

Note that sanitary isn't good enough for this method. Absolute sterilization of everything except the yeast is required.

 

[UTDoug]

Thanks for the link!

I am a believer that yeast are not as fragile and delicate as everyone is making them out to be, at least from my limited experience. What I'd like to be able to do is have 3 or 4 tubes of different white labs strains in my arsenal. When it comes time to brew, I would use 1/3-1/2 of the yeast in the tube to start my beer, and then add a sugar water/agar solution to the tube to grow replacement yeast and then put the tube back in the fridge in a day or so once some multiplication has started. You really wouldn't need much multiplication at all, just something to dilute the mixture and keep the yeast alive and you could get lots of uses out of one vial.

Anyone tried this? What did you add to the tube to keep they yeast alive

Thanks,
Doug

 

[dougjones31]

You can use yeast 4 times without a problem.

I would study up on freezing yeast if I were you. All you need is some Glycerin from the drug store.

I would buy 1 white labs tube and make a starter. 1 ltr starter. Then I would split that starter into 10 or 20 small samples and mix them with 1/3 water/wort, 1/3 glycerin and 1/3 yeast. Then freeze them in a NON frost-free freezer. Or if your freezer is frost free then I would make sure to put the small samples in a container and pack it with freezer packets. You do not want the defrost cycle to ruin your yeast.

Then you can use 1 of the small frozen samples to make a starter. Then you can pitch on top of the yeast cake 3 times. Saving the yeast cake in between batches for up to 3 months.


That would make you pretty self sufficient on the yeast.

 

[dougjones31]

You do not want to do what you suggested because you want to be able to keep track of which generation your yeast is. Remember 4 uses is all I would trust the yeast for.....after that the yeast starts mutating and you cannot count on it giving you the same performance.

If you use 1/3 of a tube then add sugar to the tube then you will have 2nd generation yeast in the tube....after the 4th use then you would start having dangerously old, possibly mutated yeast in the tube.

 

[UTDoug]

Thats a good point; for now, i'm going to squeeze 2 batches out of a tube and then do the refill, and maybe try to do that once maybe twice depending on how lucky I feel.

Hook'em,
Doug

 

[azhophead]

I am just getting back into brewing after a 5 yr hiatus after brewing 9 yrs. Too many stupid reasons to mention why I waited 5 yrs but anyways…I always re-used my yeast up to 5 generations sometimes and had great success. I basically followed the bible oh how to capture and reuse the yeast. I take my strubb and split it into 6 or 8 12oz brown sterilized beer bottles, then cap and print labels including Generation #, Date harvested, and Yeast type. I used yeast up to a year old and usually brewed something before it went bad just to have more yeast.

When you’re ready to use it wash it according to the bible use in a starter to get cell count up.

I always make a ½ gal to 1 gallon starter no matter where the yeast comes from; I believe that is why I always had active fermentation within 6 to 8 hours of pitch.

 

[dougjones31]

Be careful pitching 1 gallon starters because that ends up being 1/6th of the volume which can water down the taste of your brew. I would cut back to 1 quart starters if I were you.

 

[homebrewer_99]

I don't do any more than 1 quart myself. Mostly 1/2 quart sized.

 

[azhophead]

I should re-phrase my starter size, it was actually 1 -2 quarts, not gallons So you are both correct. It depends on batch and beer size of course.

 

[gauthierk]

I'm running into the same question. I just finished up a belgium and a Mead and I want to save the yeast from both of them. I have mason jars that I ran through the dishwasher then soaked in sanatizer as well as the solvent I clean my carboy's with. I have both cakes in my fridge where I have been washing the yeast of the leftover wort and must. I haven't quite figured out what the procedure would be for freezing or just long term storage for them...

 

[Pumbaa]

Gauthierk, here read this and this