Using Yeast Cake from secondary... Can I?

[Brocster]

Hi all,

I have a 1.070 strong ale that has been sitting in a secondary for four weeks and I am going to rack to a keg tonight. There is the typical trub on the bottom.

Sunday I am going to brew an American stout and was wondering if I could use the cake from the strong ale secondary, or, if it would be alright to harvest the yeast from the secondary and get a good starter going. Is it better to just use primary yeast cake for dumping a batch onto? And if it is ok to use the cake in the secondary, is it possible to "keep" the trub from tonight (Friday) till Sunday, and how?

Thanks!

 

[rsmith179]

You're right on the edge for the amount of alcohol in your beer which may negatively affect the yeast you have in your secondary. You should be able to harvest some of the yeast in the secondary, however, the best time to harvest yeast is directly from the primary. Healthier yeast in the primary compared with the secondary.

If I were you, and were going to re-use this yeast, I'd harvest some and try making a starter batch with it. Nothing huge, just .5-1L would do. This will basically help proof your yeast to ensure that you have viable yeast for your next batch.

I would also recommend checking out some of the posts regarding yeast washing. I wash my yeast from the primary after every brew and am able to store that yeast for up to 6 months in the fridge. Doesn't last that long with all the brewing going on, but I love not having to pony up $8.00 for each vial of yeast.

 

[mmb]

Harvesting from secondary is also selecting for the less flocculant yeast from that strain.

 

[GoBrewers]

IMO it sounds like a pretty bad idea. 1.070 is a pretty high gravity brew to consider re-using yeast, and that's if it was just off the primary, when the yeast were fresh.

Your yeast in secondary said goodbye to log phase weeks ago and living in beer is genetically selecting against the yeast that would give you the best fermentation in your next brew. You could make a starter, but you're starting with these undesirable variants.

So long story short - can you? Yes. You'll still have beer.
Should you? I vote no - why tarnish a 5 hour brew day with bad beer when you can just pitch fresh yeast.

 

[Brocster]

Perfect info everyone - I really appreciate the help!!!