How to get yeast from beer

[TimW]

Another useful trick when yeast is unobtainable, like now in the UK.

You need a bottle of BOTTLE CONDITIONED ale. Leave it to stand upright
for a few hours so the yeasty sediment is all in the bottom of the
bottle. Open it and in a single motion so as not to disturb the sediment
pour off all the clear beer into a glass leaving the last bit of cloudy
sediment in the bottle.

put a small bowl on the scales and pour the sediment into it adding a
little water and then flour to make a 50:50 ferment. Beat with a fork,
cover and leave until bubbling. Double the amount, beat, cover and leave
again until you have enough active ferment to use as a bread starter.

A drop or two of lemon juice (no more) helps the yeast along. Beating
some air into it is good too.

TW

[Peter Flynn]

On 31/03/2020 19:34, TimW wrote:
> Another useful trick when yeast is unobtainable, like now in the UK.

I bought several boxes of dried yeast in Feb but I'd like to try some
home-made. As some microbiologist said, there cannot ever be a shortage
of yeast — it's everywhere.

> You need a bottle of BOTTLE CONDITIONED ale.

I think that my favourite German Hefeweizen meets this criterion, but I
don't know what UK ales are bottle-conditioned. Does it say on them, or
does someone have example brands?

> put a small bowl on the scales and pour the sediment into it adding a
> little water and then flour to make a 50:50 ferment.

50:50 by weight, presumably.

> Beat with a fork, cover and leave until bubbling. Double the amount,

Do you mean add the same amount of flour as you originally used? Or does
this mean add twice as much as you originally used?

> beat, cover and leave again until you have enough active ferment to
> use as a bread starter.
>
> A drop or two of lemon juice (no more) helps the yeast along. Beating
> some air into it is good too.

Thanks for the tips.

Peter

[TimW]

The way I do it is to keep the ferment from the beginning 50:50 by
weight liquid to flour. So if you find you have 20 or 30g of beery
sediment you might add water to make it 50g, then 50g of flour, then
beat and leave until your 100g of ferment is bubbling well. Then make it
up to 200g of ferment (adding 50g water, 50g flour), leave, then make it
up to 400g of ferment (adding 100g water, 100g flour) etc.

Beers with live yeast in the bottle seem to be labelled as 'bottle
conditioned' in the UK. I don't know if it's a requirement. They
normally say a little natural sediment, but often the yeast count is
quite low. The German Hefeweizen, wheat beer, weiss beer may have live
yeast in the bottle but I think the white cloudiness is often the
product of a different process and is no guarantee of live yeast.

All the old English manuals of baking I have seen say 'get your yeast
from the brewery'. Brewers yeast = Bakers yeast in the British tradition.

TW

[graham]

Well they are both derived from cereal grains. Of course, over the years
breeding has developed different strains for brewing and bread.

[TimW]

My understanding is that in the English tradition, in these climes beer
has always been brewed in every town and village and excess yeast is a
by product of brewing so bakers have always used brewers yeast, they are
the same thing.

TW