washed yeast (from previous batches) as yeast nutrient?

[Elysium]

I have seen somewhere that people pour yeast (harvested from previous batches) in the boiling wort (like 10 minutes before the flame-off) as yeast nutrient. Is this something you guys do? Or is this a good idea at all?

I heard that dead yeast provides nutrient for the new yeast cells that we pitch after the wort cooled down.

 

[BradleyBrew]

most yeast nutrient contains dead yeast.. I believe they are called dead yeast hulls. So if you pour yeast into your boil you would be effectively adding soon to be dead yeast. You would probably only need a teaspoon at the most.

 

[k_mcarthur]

This is an interesting idea, I may try this just to see. Thanks for the idea. Maybe try first in a starter.

 

[slow_boat]

Yes, there are some people that re purpose their previous batch of yeast as a nutrient. It's generally dumped in at the beginning of the boil. Yeast itself contains many vitamins and minerals, and the boil will break most of these down for the next generation of yeast to feed off. However, most of these vitamins and minerals are already found in the malt. Malt lacks Zinc though, which is critical. Your dead yeast will contain some Zinc, but it is hard to tell how much. For a five gallon batch I would add a tablespoon or two of slurry, but if you are looking for something more, you can always get some Zinc Sulfate tablets.

 

[JimRausch]

I did this in a batch of cider that I brewed last year, before I picked up some yeast nutrient. I figured that cider might not have all the micronutrients that wort has. Added 2 TBS. of a yeast slurry in the last 10 minutes of boil(I also added 2 lb honey and 1lb steeped crystal10, so was boiling that). Necessary? I don't know. Did it hurt? Nah.

 

[Elysium]

Anyone else who have tried this?