Racking smaller beer onto yeast cake with lots of trub.

[italynstallyn44]

I am thinking of racking an upcoming brew onto an existing yeast cake but have a couple questions because I have never done it before. First off the beer currently in the primary is a bigger 1.073 IPA. I used two packs of US-05 yeast. The next beer I'm brewing is a 1.049 Golden Ale. I'm worried about a couple things. First I know it's usually better to brew the smaller beer first and rack the larger one onto the cake. Will I be OK racking such a small beer onto that cake? I guess I could scoop some of the yest cake/trub out and rack onto that portion of it.

My second worry is the IPA had over 7 oz. of hops in it which caused a lot of trub to go into the primary. I tried to filter some out, but a lot still got in. The golden ale isn't going to be hop heavy, is this going to cause an issue?

Am I just safer using a new pack of US-05 for the Golden ale?

 

[ColoHox]

Yes, it would be safer to just use a new pack.

That yeast in primary would definitely still ferment a beer. However, it is tired from the high ABV and all those hops. It is also likely, that by just racking your beer onto the cake, that alot of the hop flavors would carry over. If you were to reuse the yeast, you would be best served by collecting a portion of the cake (avoiding trub and hop debris) and pitching that.

 

[Natdavis777]

Another thing to take into consideration is how the end product will taste. If it is something that you like, it could be hard to replicate because you don't know how much yeast was used. It would be best to wash the yeast and pitch a controlled amount.

As for washing yeast, I try not to on any higher abv beers or anything with a decent amount of hops. This helps ensure I'm getting healthy, unstressed yeast. For example, my next brew will be 10gal of an American wheat ~5.0ABV and 20-30Ibu. Should net me 8 jars of healthy yeast that I can use to make staters for a beer of any gravity

 

[Calder]

Do NOT rack onto the cake. That would be a massive over-pitch. Going down in gravity just makes the over-pitch much worse.

Take about a quarter or less of the cake and pitch onto that. Really, no more than a quarter, and less is better. That cake probably has somewhere in the region of 8X the recommended amount of cells for pitching into this lower gravity beer.

Don't worry about the yeast being tired. If you pitch about the right amount, it will reproduce and make fresh new yeast to ferment your new beer. If you over-pitch, you will get very few new yeast, and the cells will be tired.

Don't worry about the hops, they are well spent, and should not be an issue.