Reusing yeast

shaynm · Feb 9, 2011

This is the first time I have attempted to save the yeast that is in the bottom of the primary fermenter. I am about to make an English Brown ale and I wanted to get some advice as to whether I should introduce this yeast into my new batch.

The process of harvesting the yeast was as follows. We sanitized our container, a bowl and a plastic spoon. We scooped 3 large spoonfuls of the troob from the primary fermenter and mixed it with about 2 cups of runoff from the MLT we had kept from our ESB. The troob was mixed so it was a good thin slurry then we poured the mixture into the container, put the airlock on it and left it at room temperature to see if anything would happen.

We have had a good amount of activity. It gets agitated 2-3 times a day and after the yeast settles you can see these little CO2 explosions on the bottom of the yeast bed (similar to what we see when we make a starter). I was not really sure how this was going to work and it was more of a "lets see what happens" experiment but now I am considering using this yeast this weekend. Recently activity has slowed and the yest seems to have gone dormant.

Should I pitch this yeast into my next batch? Is this enough yeast to get a good fermentation? Should I add another smack pack of the same yeast? Are there any steps I should take before introducing this yeast?

I posted some pics of the container below to help you get an idea of the volume of the culture. It is a 1/2 gal container. Thanks!

Nick

Justibone · Feb 9, 2011

If it is the same size as your normal starter, I'd say go for it.

If you have any kind of infection problems then re-using yeast is a bad idea. It's also not always the best idea to re-use an entire yeast cake, but the way you've done it seems okay. If it smells good, it probably is good.

I wouldn't experiment like this with a brew you haven't done before, though. You want to know how it went by tasting the final product. I predict it will be fine.

wilserbrewer · Feb 9, 2011

shaynm said:
. We scooped 3 large spoonfuls of the troob from the primary fermenter and mixed it with about 2 cups of runoff from the MLT we had kept from our ESB. [/IMG]

I hope you boiled the runoff prior to adding it to your yeast??

EoinMag · Feb 9, 2011

Normally if doing brews pretty close to each other, I'll just use a ladel to scoop out 2-3 ladel fulls of yeast and put it into a sanitised jar and screw the lid on, then once it settles out pour the beer off the top leaving a small amount to cover it and stop it drying then pitch in a few days.
Ideally I pitch it straight into the next brew end to end stylee as I know the yeast was just active and will kick off again pretty quickly, but storage for a week or two as described with no washing is no biggie.