Harvesting yeast

[oxford brewer]

Thanks to changing from supermarket milk to dairy delivered, we are getting our milk in nice(SHINY) glass bottles instead of plastic containers.
I want to have a go at harvesting and washing yeast with a view to reusing(yeast is safale 04,which is readily available in dry form,but start somewhere ,the experience may be beneficial if i choose to buy a liquid yeast? ).
Whats the best method for this procedure Do i need to wash all of the remaining yeast cake?

Colin

PS just checked and all the bungs i have fit the milk bottles nicely

[tribs]

I have just used this method to wash the yeast but did not notice a visible layer in the second vessel. I left it in the fridge for a few days and now there is a noticeable layer of yeast below the nearly clear water.

I am reluctant to disturb it further though. I will probably just leave it as is instead of pouring off the liquid and then transferring the yeast layer from the remaining trub. I have stored the cake in the fridge for months without washing previously and this looks a lot cleaner than that.

[PieOPah]

The last time I tried to store yeast some very strange things happened.

I had used the yeast in a stout so I was expecting some dark colour in the yeast. Anyway, I sanitized a jar and poured in the slurry (there was some stout left over in the fermenter so used this to loosen).

After a few days, I poured off most of the stout leaving behind only the slurry. To this I added some preboiled water and mixed it up a bit.

After a couple of days, the slurry had completely settled and I was left with a stout looking covering on the top (obviously a lot of the colour came out of the yeast!)

After about another week, some of the slurry had started to float. What I was left with was a dark liquid trapped inbetween 2 layers of slurry.

It looked strange and I thought that there may have been a problem. I didn't want to risk any beer by reusing this yeast so threw it away!

I think that the next time I use yeast I will make a big starter and split this rather than saving anything. If I was to reuse a yeast cake then I would just repitch straight onto it.

[PieOPah]

Never skimmed even when I use my fermenting bucket.

Not seen the type of activity I had before when saving yeast....

[tribs]

I used the Wyeast yeast washing method.

In the second vessel you had trub coloured trub on the bottom. Then a thin layer of white yeast. Followed by the almost clear liquid on top.

Nothing floating on top though.

I think the theory is if you pour off the clear liquid and then pour the white yeast layer into another container without disturbing the trub you end up with a fairly pure quantity of yeast without any spoiling elements which can be stored for longer than when mixed with trub and beer.

[PieOPah]

If anybody fancies taking photos of the various stages of washing yeast then I think it would be great.

Part of the problem I think is that I don't know what I am looking for when washing yeast so haven't wanted to risk it.

A bit of time-lapse photography would be perfect

[PieOPah]

If you made a starter with it you could have tasted for infection.

Never thought about that

Anyway, I am going to try and recover the yeast from the bottom of my keg when I am done. Still have some there

[stringy]

What yeast have people succesfully harvested from bottle conditioned beers??
I have failed on several different attempts, but have since read this article:
http://byo.com/departments/1361.html
I think I will give it another attempt, this seems a lot better than how i have previously tried.