Reusing The Yeast Cake - How Many Times?

[andreic]

Hi,

I recently cultured up the yeast from a Coopers Sparkling Ale. I used this to brew a Coopers Sparkling Ale kit. I racked this to secondary after a week, then when I racked this off to bulk prime a week later, I dumped a Coopers Pale Ale kit on the yeast cake left in the seondary. I am now following the same brew procedure for this kit too (1 week primary, 1 week secondary).

Can I reuse the yeast cake from secondary again for my next brew? How many times can I do this before I should start again?

cheers,

Andrei

 

[GMK]

i definitely would not use it more tahn 6 times - however - i know of a micro in NSW that uses this method 16 times.

But - if u make big beers - eg up around 7% - then i would not use the yeast cake that many times as the higher the alcohol the greater stress put on the yeast and the greater the chance for mutation.

Hope this helps

 

[andreic]

Thanks GMK,

sounds like I could safely reuse it another couple of times if I wanted to as long as cleaning / sanitation is OK. I'll probably only use it one more time - seems easy enough to culture up another Coopers yeast if I need to.

cheers

 

[PostModern]

Are you doing full wort boils? No matter how good your sanitation is, chucking in unboiled tap water will introduce microorganisms which adapt to the yeasty environment and increase in concentration batch to batch.

You also need to manage the buildup of trub from batch to batch. I've found that 3 batches is about the limit for dumping kits onto yeast cake. After that, off flavours start to creep in. A better strategy is to retain some yeast from the primary and run up a clean starter, but without isolating the yeast like the platers/streakers do, you get infections building up in the culture over the generations. I guess you could get away with making a fresh starter from a small sample every 3 batches or so, but I'd just make a fresh starter from a bottle of Coopers and avoid the possibility of local infection.

I also harvest from primary, as I reason that the yeast there have had less time in a high alcohol environment and are likely to be healthier. The downside is the extra trub and hop debris. Also, yeast cells that remain in suspension all the way thru primary and into secondary may over time alter the strain to be less flocculative, which may be a good thing?

 

[ozbrewer]

do a google on yeast washing, or acid washing yeast, you can use the yeast as many times as you like if you wash it well.......


Do a search here for yeast washing too, Chiller wrote some stuff on it, I had a 1056 that i used 5 times, then used it twice for ginger beer, and then again for another ale, no off flavors at all, you just got to wash it