Yeast washing: how long can yeast cake stay in carboy?

[abledsoe]

I was planning my first attempt at yeast washing with a batch of beer that was about ready to be bottled. Due to a last minute schedule change, I needed to go ahead and bottle the beer yesterday afternoon. I boiled the water and jars for the yeast but they weren't cool in time to wash/harvest yesterday. I left the yeast cake in the carboy and put the airlock back in. I plan to wash the yeast today after work. Will the yeast still be okay after sitting 12-14 hours in the carboy, or should I not waste my time with this one?

Thanks!

 

[WoodlandBrew]

Yes, that is fine. For details see here:
http://woodlandbrew.blogspot.com/2013/01/abv-effects-on-yeast.html

But in most cases washing is a waste of yeast and time. For details see here:
http://woodlandbrew.blogspot.com/2012/12/yeast-washing-exposed.html
http://woodlandbrew.blogspot.com/2013/01/yeast-washing-revisited.html

 

[abledsoe]

Thanks for the info!

 

[Biobrewer]

But in most cases washing is a waste of yeast and time. For details see here:
http://woodlandbrew.blogspot.com/2012/12/yeast-washing-exposed.html
http://woodlandbrew.blogspot.com/2013/01/yeast-washing-revisited.html

Can you clarify in a bit more detail what exactly was done here? There is very little information as to how the experiments were conducted, how the analysis was done and how the data was interpreted.

As a scientist myself, a lot of this seems a bit "hand-wavy", as we say in the field, in the absence of specifics. Also, the process you are referring to is "rinsing", not yeast "washing". "Washing" is typically used in the case that a chemical washing agent is used (i.e. acid wash). Rinsing typically implies use of only water with no chemical agents added during the process.

Also, rinsing is unlikely to significantly reduce the bacterial load of a slurry, which is one of the main reasons breweries typically wash their yeast with something like an acid solution, which will reduce the bacterial load.

Looking forward to learning a bit more about how you arrived at these conclusions. Cheers!

 

[WoodlandBrew]

I agree. The yeast washing as commonly referred to by home brewers is better described as yeast rinsing. The terms are better defined in my book. Take a look through my blog for details on cell counts to see how they were conducted. It's basically the White Labs procedure.

 

[Biobrewer]

I agree. The yeast washing as commonly referred to by home brewers is better described as yeast rinsing. The terms are better defined in my book. Take a look through my blog for details on cell counts to see how they were conducted. It's basically the White Labs procedure.

Nice! I'll be sure to take a look at it.