Question about reusing yeast.

[Jwerner23]

Ok, I have been breing for about a year now. I have always used dry yeast packets and buy a new one every batch. I currently have 2 beers I am going to brew a week apart from one another, an IPA and a wheat. I was wondering if I could brew the IPA and let in ferment in the primary for a week before trandfering to secondary, which I normally do, but have my wort from the wheat cooling and just put it on the trub from my IPA in the primary. Would I have to pitch another packet of yeast or would this just work with the yeast from the last batch? Thanks for any advice on this, I am just wondering if this would work.

Thanks

 

[boydster]

You can do that, just remove about 3/4 of the yeast cake before you put the new wort on top. You want the yeast to reproduce a little when fermentation kicks off, and if you don't remove any yeast, there will be such a large yeast colony already present that there will be practically zero cell division, leaving only old and scarred yeast cells to ferment your wheat.

 

[BigFloyd]

What boydster said. 25% of that yeast cake will be more than enough cells.

Tossing a wheat onto a cake from an IPA could give you a rather hoppy wheat beer.

 

[msa8967]

Usually people reusing yeast (either by washing or slurry) recommend going up in IBU or from lighter to darker but not in reverse (darker to lighter, high IBU to lower IBU).

 

[Jwerner23]

Thanks, I will probably reverse and do the wheat then put the IPA on the wheat trub. I was just thinking to do the higher gravity beer first. The IPA will be higher gravity coming in around 1.070 and getting to around 1.015, the wheat should be around 1.053 and getting to around 1.015. Will this still work this way?

 

[msa8967]

Yeah...low gravity, lower IBU and lighter color to start and then go higher gravity, higher IBU and color for the next brew.

What yeast strain are you using?

 

[Calder]

Tossing a wheat onto a cake from an IPA could give you a rather hoppy wheat beer.

Usually people reusing yeast recommend going up in IBU or from lighter to darker but not in reverse (darker to lighter, high IBU to lower IBU).

Yeah...low gravity, lower IBU and lighter color to start and then go higher gravity, higher IBU and color for the next brew

I really don't think it makes much difference. If you take a pint of slurry, and let's assume half of it is solids, then the carry over of flavors in the liquid is only about 1.25% of the original - negligable. If you store it for a few day in the fridge and drain the liquid, it is even less. I don't think the order of the beers is really a problem.

 

[BigFloyd]

I really don't think it makes much difference. If you take a pint of slurry, and let's assume half of it is solids, then the carry over of flavors in the liquid is only about 1.25% of the original - negligable. If you store it for a few day in the fridge and drain the liquid, it is even less. I don't think the order of the beers is really a problem.

It can make a difference if reusing yeast harvested from a higher ABV beer (like the OP's 1,070 IPA). I recall reading comments from Chris White about not reusing yeast from batches much higher than 6% due to the potential for petite mutations.

 

[Jwerner23]

I was probably going to use 05 yeast

 

[Calder]

It can make a difference if reusing yeast harvested from a higher ABV beer (like the OP's 1,070 IPA). I recall reading comments from Chris White about not reusing yeast from batches much higher than 6% due to the potential for petite mutations.

As you say yourself, "petite mutations". I don't believe you would notice much difference on a single re-use. Every time you reuse a yeast it mutates, reusing it from higher gravity beers just accelerates the process. On a single reuse from a high gravity beer you will not notice any difference. If you do this multiple times, you may then start to notice a change in yeast fermentation properties.