Yeast Washing and Storage

[Petrolhead]

I have just ordered up a separatory funnel and some 50ml centrifuge tubes to give yeast washing a try. It looks fairly easy and could save quite a bit of money. Especially if I use the brewers method of cost calculation by ignoring the money you spend on the kit.

Once washed I have the option of storing in the fridge or, with a little more expenditure, freeze in glycol. Any advice on the best route? I’m tempted to just refrigerate as I get about 6 months storage, preferably used earlier, but like the two years in the freezer as the hoarder in me wants to build up a yeast collection.

What are your thoughts?

Cheers Nic

 

[Dutto]

I've never stored any yeast in a frozen state.

I may be terribly wrong, but I have always been given to understand that freezing a yeast cell results in the water content expanding which results in a massive reduction of live cells left to reactivate.

However, I do know that a yeast that has been stored in a fridge for a month at 4*C has reactivated okay, after slow warming and being made into a Yeast Starter using Malt Extract.

 

[MyQul]

I've never stored any yeast in a frozen state.

I may be terribly wrong, but I have always been given to understand that freezing a yeast cell results in the water content expanding which results in a massive reduction of live cells left to reactivate.

However, I do know that a yeast that has been stored in a fridge for a month at 4*C has reactivated okay, after slow warming and being made into a Yeast Starter using Malt Extract.

Freezing yeast on it's own will kill it by the ice crystals exploding the cells but the glycol stops this

 

[Petrolhead]

Well I’ve decided to go the freezing route.

I have bought a separatory flask, at one litre maybe a little small but ok to start with, about £16 on fleabay, 20 centrifuge tubes, 50ml, and very cheap, and 500ml of glycerine for £6 so not a big investment.

First out of the brew fridge is a Christmas present Wilko ale so I will give that a go. Maybe only half a dozen test vials.

I have also bought a 1 litre conical flask and will get a stir plate by the weekend. Won’t need this for a while but a good starter seems to go hand in hand with using farmed frozen yeast.

I feel quite the microbiologist.......

 

[MyQul]

Get in! I quite like messing about with yeast too. The separatory flask vid on youtube looks cool but personally I prefer not to wash yeast. I also like K.I.S.S. brewing in all area's including 'yeast wrangling' and just keep my yeast under beer in a jar in the fridge

 

[Drunkula]

Half an hour ago I put on a starter with yeast I've had in the freezer for a month. I got my glycerin from Boots and made a 50% solution and put it in the little jam jars you get in gift sets and sterilised them in the pressure cooker. I'll let you know how it goes. The yeast was from a previous starter I used to culture up Fuller's yeast.

EDIT: 18 hours later and it's got plenty of froth on the top. I did put a really quite small amount of yeast into a litre starter and I'll be stepping up properly from now on as I hear too much starter wort causes lots of scarring on the yeast because of the amount of budding that goes on.

This has worked crazy well, as long as this is really the frozen yeast growing and not some boozy ligger.

 

[Ghillie]

Well I’ve decided to go the freezing route.

I have bought a separatory flask, at one litre maybe a little small but ok to start with, about £16 on fleabay, 20 centrifuge tubes, 50ml, and very cheap, and 500ml of glycerine for £6 so not a big investment.

First out of the brew fridge is a Christmas present Wilko ale so I will give that a go. Maybe only half a dozen test vials.

I have also bought a 1 litre conical flask and will get a stir plate by the weekend. Won’t need this for a while but a good starter seems to go hand in hand with using farmed frozen yeast.

I feel quite the microbiologist.......

If you're going the starter and stir-plate route, then why not overbuild your starters before pitching. This eradicates any need to wash or harvest yeast and makes the whole process a lot easier.

You'd be better with a 2L flask though, 1L isn't up to the job really.

http://brulosophy.com/methods/yeast-harvesting/

http://www.brewunited.com/yeast_calculator.php