Keeping a liquid yeast culture going - advice please

[BOBTHEukBREWER]

Hi all, my thoughts are to burst the inner pack, then when the outer swells up, empty it into a carefully sterilised bottle (sealed with airlock) containing a boiled, then cooled, solution of 1 oz malt extract in 1 pint of water. When there is a vigorous fermentation, add half to my 6 gallon brew and add half a pint of water containing half an ounce of malt extract, boiled and cooled to the remainder. Feed with more of the same, each time discarding half the quantity, until my next brew. Thoughts and your own techniques, please.

 

[Funkenjaeger]

There is plenty of info out there on making yeast starters, which you should read if you haven't already.

First, I think you will want a starter bigger than one pint, especially if you're thinking of only pitching half of it, and ESPECIALLY if you're doing any kind of bigger beers. A 1-liter (~1qt) starter is pretty normal, or even bigger for bigger beers.

Second, I don't know if there's much reason to pitch half of it, rather than pitching like 80-90% of it. The yeast in the starter should be able to grow back up from a smaller population just as easily, since you'll have the time.

Also, are you sure you want to be using the same yeast that often?

 

[BOBTHEukBREWER]

Thanks for that. In the UK, a leading brewery has kept its yeast strain going for over 20 years - so yes, if the finished brew is consistent, I would keep it going. I will go looking for advice on yeast starters.

 

[Funkenjaeger]

In the UK, a leading brewery has kept its yeast strain going for over 20 years - so yes, if the finished brew is consistent, I would keep it going.

Well, my comment was more specifically in regards to using just one yeast for all your beers - I don't doubt that with enough care you could keep one strain going for a long time. Most people use at least a few different yeast strains to cover various beer styles. I use at least 2-3 strains most of the time, and keep a half a dozen or so around to cover more styles.

If you like to stick to brewing within a narrower style range, or stick to using just one "house strain" even in styles where another yeast may be more appropriate (like what a number of craft breweries do), then yeah, continuously propagating one strain should do you well.