Reusing yeast

[jslive4now]

Hello all!!! Question... Tonight I will be kegging a brew that used WLP001 yeast.. Tomorrow I will be brewing a new beer that I would like to use the same yeast for.. I don't want to pour the new wort directly onto the current yeast cake.. I do not want to over pitch.. I would like to use some of the cake which leads me to my question... How much should I use and how should I store it till I'm able to use it tomorrow afternoon??? Should I bother washing ?

Your thoughts and advice are much appreciated and thank you in advanced!!!

 

[CA_Mouse]

Check out the calculator at mrmalty, enter in that you are using slurry and it will tell you how much you need.

 

[Gnomebrewer]

A general rule of thumb is a quarter of the yeast cake, or use the calculator on mrmalty.com.

If you're using it tomorrow, just sanitise a jar or bottle and completely fill it with the yeast cake (mix in a bit of beer to make it runny, or add some cool boiled water). Try to get more yeast than you need, but only pitch the amount that you want to use.

Try not to overpitch - I've done it a few times and it leads to a sharp, yeasty bite in the new beer (I don't think I'm imagining it....).

 

[jslive4now]

A general rule of thumb is a quarter of the yeast cake, or use the calculator on mrmalty.com.

If you're using it tomorrow, just sanitise a jar or bottle and completely fill it with the yeast cake (mix in a bit of beer to make it runny, or add some cool boiled water). Try to get more yeast than you need, but only pitch the amount that you want to use.

Try not to overpitch - I've done it a few times and it leads to a sharp, yeasty bite in the new beer (I don't think I'm imagining it....).

Thanks Gnomebrewer!!! According to the calculator I'll need about 216 billion cells for my next pitch.. At 1/4 liter (about 1 cup, tad over maybe) would give me about 250 billion... Think I should go with that??? Or should I under picth so the yeast can grow?? Some things I've read say its important for yeast to grow.. Thoughts on that?? If u don't mind..

 

[jslive4now]

Check out the calculator at mrmalty, enter in that you are using slurry and it will tell you how much you need.

Thanks CA_Mouse!!!!

 

[Subdivisions]

Don't under pitch. The yeast will reproduce regardless of the amount you pitch. It's better to over pitch a little than to under pitch.

1 cup sounds like a good amount

 

[Brewenstein]

What @Subdivisions said. I use Mr. Malty but always pitch about 50% more. My understanding is that it is not common for homebrewers to over pitch. Following this I have good fermentations and no issues with attenuation. I also try to add a couple teaspoons of bread yeast to the end of the boil as nutrient and I use an O2 setup and hit it for 60 seconds.

 

[jslive4now]

Don't under pitch. The yeast will reproduce regardless of the amount you pitch. It's better to over pitch a little than to under pitch.

1 cup sounds like a good amount

What @Subdivisions said. I use Mr. Malty but always pitch about 50% more. My understanding is that it is not common for homebrewers to over pitch. Following this I have good fermentations and no issues with attenuation. I also try to add a couple teaspoons of bread yeast to the end of the boil as nutrient and I use an O2 setup and hit it for 60 seconds.

Thanks Brewenstein and Subdivisions!!! Appreciate all the advice!!!! Cheers!!!

 

[Gnomebrewer]

Don't underpitch. That's worse than overpitching.

1 cup sounds like a lot. Are you making a 10gal batch? That would be about right. It really does depend on how runny it is though. If I'm using fresh slurry that's quite runny, I'd use about 1 cup (6 gal batch). If it's had time to settle and the clear beer tipped off the top (so it's a nice thick yeasty slurry) I go with about 1/2 a cup.

 

[jslive4now]

Don't underpitch. That's worse than overpitching.

1 cup sounds like a lot. Are you making a 10gal batch? That would be about right. It really does depend on how runny it is though. If I'm using fresh slurry that's quite runny, I'd use about 1 cup (6 gal batch). If it's had time to settle and the clear beer tipped off the top (so it's a nice thick yeasty slurry) I go with about 1/2 a cup.

Gnomerbrewer... Its fresh.. I'm just kegging now and fermentation started 2 weeks ago today.. So its had no time so separate or clear... So little less than a cup?? All calculations using Slurry and today's Date say 1/4 littler (tad over a cup will get me about 250 billion cells, about 34 billion more than required (216 billion).. Thoughts??

Thank you!!

 

[jslive4now]

:thumbup:

 

[Gnomebrewer]

mrmalty says about 1/2 cup for 250billion cells (90%viability, mid-range yeast concentration and non-yeast percentage). A cup should be ok though.

 

[CA_Mouse]

As previously stated, as homebrewers, risk of over pitching is extremely unlikely to cause issues. Under pitching is more of an issue. I believe that you will be fine with using a cup of your slurry for this beer. I'm using 4 oz of compacted yeast from 2 months ago that I'll pitch into a starter and should have about 6 oz of slurry at pitching time next week for a smaller beer than your's.

 

[Gnomebrewer]

As previously stated, as homebrewers, risk of over pitching is extremely unlikely to cause issues. quote]

I've heard this repeated a lot.

I don't agree with it.

I have noticed a yeasty bite to beers when I've used too much slurry.

 

[Pkrd]

I usually use a third of the cake.
I don't understand how you can say "a cup" without knowing how much trub there is, and how much beer you left on the trub.

 

[CA_Mouse]

I've heard this repeated a lot.

I don't agree with it.

I have noticed a yeasty bite to beers when I've used too much slurry.

I didn't say that it can't happen, just that it is very unlikely. Even Jamil has said it many times, as has Chris White of White Labs. Jamil was saying just recently, that having too much yeast in suspension will cause a bitter bite or too much trub transferred to your keg/bottles.

 

[KangerBrew6]

Tried and true for 23lt brews (roughly 6 US gallons) 250 ml (1 cup) for ale and 500 ml (2 cups) for lager. That's roughly about it but hey, life can be rough.