Repitching slurry - volumes?

[Graeme]

Hi guys,

I'm just looking for a bit of input in regards to harvesting yeast. I plan to harvest the yeast (White labs 002) from a stout I am bottling next week in order to use it for a brown ale I plan to brew the week after. I have read over the various techniques mainly yeast washing which I don't really plan to do as I'm just looking to save a bit of money for this particular batch, and because I'm brewing so soon after harvesting it.

I understand Mr. Malty calculates repitching volumes for 'washed yeast'. I'm just wondering how to calculate how much slurry I will need to pich as I imagine the full yeast cake will be far too much. The planned gravity on the ale will be 1.060 or there abouts.

Thanks allot!

G

 

[BBL_Brewer]

Mr. Malty calculates repitching from slurry. Probably your best bet for estimating what you need.

 

[Graeme]

I was under the impression that Mr. Malty calculated from 'washed yeast' in which case that would be a little different from what I am proposing to do. I'm just planning no pitching slurry without washing the yeast

 

[BBL_Brewer]

Mr. Malty doesn't have a washed yeast option that I know of. Check it out and see what you think. Here's the link.

http://www.mrmalty.com/calc/calc.html

 

[LakewoodHomeBrew]

IMHO - wash the yeast. You'll won't be transferring any of the trub along and you'll have a better beer. Plus, you can keep what you don't use in jars (I use baby food jars).

https://www.homebrewtalk.com/f163/why-not-pitch-your-yeast-cake-166221/

Secondly - Wyeast gives some pretty good info on yeast harvesting here:
http://www.wyeastlab.com/com-yeast-harvest.cfm

 

[Monstar]

If you aren't planning to wash, just pitch onto the cake. You aren't going to overpitch or anything.

I would reccomend washing. It doesn't cost anything extra, besides a couple mason jars, and you will get more than enough for a single batch.

I do 3 gallon batches and usually pitch about 4 tbs of washed yeast.

 

[Graeme]

If I do go ahead and wash the yeast is Mr. Malty calculating the volume I need purely from slurry? I presume the remaining liquid in the jars would not be figured in to this seen as though I would be decanting from the yeast?

Also, as I said I am brewing the following week, I should be fine to pitch directly without having to make a starter.

 

[Monstar]

Have you looked at Mr. Malty? There are two options on there; slurry thickness and percentage of non-yeast stuff in the slurry. Just make an educated guess from what you have and plug it in! Since mine is washed I usually scoot the tickers over a little to the thick side.

This is probably a no-no but I don't make starters with my washed yeast. I do however warm them up with extra wort.

 

[HHP]

If you aren't planning to wash, just pitch onto the cake. You aren't going to overpitch or anything.

I dont think this could be farther from the truth. You can easily overpitch by pitching directly onto a cake. What if you pitch a 1.045 beer onto a 1.060 cake from a beer that was properly pitched? It would be even worse if you did this several batches in a row.

 

[Monstar]

I dont think this could be farther from the truth. You can easily overpitch by pitching directly onto a cake. What if you pitch a 1.045 beer onto a 1.060 cake from a beer that was properly pitched? It would be even worse if you did this several batches in a row.

I could definitely be FURTHER, hehe. Sure, it would be better to pitch the correct amount, I won't argue that. Thats why I wash my yeast and don't pitch onto cakes myself.

I just know a lot of people do it with success, and that from what I have read it would be very hard on the homebrewing scale to pitch so much yeast that it would have a negative effect on the finished product.

 

[zeno27]

I repitched from slurry over the weekend. 100 mL of reasonably thick slurry gave me about 170 billion cells (estimated from dilution and haemocytometer counting). For 1.060, you might need a little bit more, but 1/2 cup or so of slurry should be in the ballpark.

edit: numbers for 5 gallon batch

 

[JonM]

When I use washed yeast, I wait until it packs down to the bottom of the jar, and is packed as tight as it's going to be. That makes it easier to calculate using Mr Malty because you're only using "thick slurry." Then I just eyeball the level of the thick slurry against those ml measurements on the side of the mason jar and that gets me close enough.

But if you're pitching washed yeast that's more than a couple days old, you should use a starter anyway.

 

[Graeme]

But if you're pitching washed yeast that's more than a couple days old, you should use a starter anyway.

I've heard slurry can be pitched up to two weeks, anything after than you should be making a starter. Thats part of the motivation for me to do it, I don't want to buy DME or yeast for my next batch

 

[HomebrewMTB]

It's easy to wash the yeast. Just dump some sterile water in the fermentor, shake it up, let it settle for about 20 minutes, pour the liquid into large sanitary vessel, let that settle for about 20 minutes, then finally pour off the liquid into 4 or 5 smaller jelly jars.

That said, if you are careful with your process and end up with very little break material and hops into your fermentor, you could just pitch the slurry as you are proposing. Only use 1/4 -1/5 of the total amount and you should end up with the same result, just with a negligible bit more trub in your second batch.

 

[JonM]

I've heard slurry can be pitched up to two weeks, anything after than you should be making a starter. Thats part of the motivation for me to do it, I don't want to buy DME or yeast for my next batch

I think you're right and it'll be okay for a week or two.

Wait until you get a whole collection of different kinds of yeast going - it's awesome! I bought some 1056 last November and brewed who knows how many batches with multiple generations of that same yeast. Definitely cuts down on the $ needed for brewing.

 

[Graeme]

Wait until you get a whole collection of different kinds of yeast going - it's awesome! I bought some 1056 last November and brewed who knows how many batches with multiple generations of that same yeast. Definitely cuts down on the $ needed for brewing.

This what I am most looking forward too! Cheers for the advice! :rockin:

 

[Monstar]

Wait until you get a whole collection of different kinds of yeast going - it's awesome!

Totally! Best part. I have like 6-8 choices on any given brew day... you're gonna love it.

 

[LVBen]

I think you're right and it'll be okay for a week or two.

I'd make a starter at 1-2 weeks anyway just so that the yeast has time to 'wake up'.

 

[LVBen]

Definitely cuts down on the $ needed for brewing.

Yeah! Seriously! Getting yeast prices down to about $1 per batch is AWESOME!!!