Yeast Pitch Question

[brew703]

Going to possibly brew a 1.057 PA tomorrow using 1056 slurry harvested in August.
Couple Questions:
1) According to Mr Malty, I need 119B cells, which equates to approx. 4 oz of slurry. Without measuring I assume what I have in these two jars will equate to 4+ oz once I decant. Thoughts?
2) Don't really feel like making a small starter. Can I simply warm to pitching temp and pitch both jars?

 

[brew703]

Not sure why the photo posted sideways. It was correct on my laptop. The slurry contains no hop debris.

 

[tri_clamp_ninja]

Yea I would suggest decanting and pitching both. Best case scenario you slightly over pitched, no worries. Worst case scenario you slightly under pitch and won't see the activity you are used to which in that case you can always just smack an additional pack without doing a starter or use other yeast you may be able to harvest from a different batch (if any available and the same strain of course).

 

[cladinshadows]

2) Don't really feel like making a small starter. Can I simply warm to pitching temp and pitch both jars?

If you're just looking for permission, then permission granted - godspeed and good luck! Sometimes it works out fantastically.

However, based on my experience with the Mr. Malty slurry calculator, 4 oz. seems like a surprisingly small volume for yeast stored for 3 months in questionable (i.e. not laboratory-controlled) conditions. When I run your numbers it's looking like you'd need over 500mL of slurry when you account for the decline in viability over time. Even if you maximize the sliders (0 non-yeast, max thick slurry) you're still looking at about 260mL, and those conditions are very likely not reflective of what you've actually got.

Making a starter is a hassle, but it's cheap insurance that you won't ruin a whole batch of beer which took a LOT more work and money to produce!

 

[balrog]

Agree a bit with @cladinshadows. HomebrewDad's calc, for 13Aug harvest, gives 47% viability so you'd need about 7oz slurry (typical 2bl/ml).

 

[RM-MN]

Mr. Malty is a horrible pessimist and assumes that your yeast cells commit suicide at a very high rate. Kept refrigerated (proper storage) the yeast will be viable for much longer than predicted. Furthermore, if you aerate your wort well prior to pitching the yeast will quickly grow to much larger numbers so you don't have to pitch as much. I've seen several posts about the need to pitch at least a 2 liter starter if you are making a lager but Gordon Strong, a three time winner of the Ninkasi award has stated that he often pitches just a single smack pack in his batches of lager.

http://www.woodlandbrew.com/2012/12/refrigeration-effects-on-yeast-viability.html

 

[cladinshadows]

I'm certainly not trying to say the Mr. Malty calculator is the end-all-be-all of viability calculation, but it is the reference that brew703 mentioned using. I'm sure we can agree that the actual viability of slurry stored in this manner is probably somewhere between the Mr. Malty data (cells die EXTREMELY quickly) and the woodlandbrew data (viability is nearly unchanged over time). Additionally, neither one touches on the vitality of the yeast, which many would argue is even more critical than the cell count.

Will brew703 ultimately end up with "a beer" either way? Certainly. But if he's looking to make the "best beer" possible then a starter would be beneficial.

 

[brew703]

If I had to guess there is probably more than 4 oz of slurry once I decant. I've done it before and it worked out fine but I understand that a starter is beneficial.
Let me ask this.. if I simply keep both jars and add that to my flask (without decanting) and put it on the stirplate would that work as well as making a fresh starter?

 

[kh54s10]

If I had to guess there is probably more than 4 oz of slurry once I decant. I've done it before and it worked out fine but I understand that a starter is beneficial.
Let me ask this.. if I simply keep both jars and add that to my flask (without decanting) and put it on the stirplate would that work as well as making a fresh starter?

No, All that would do is make your yeast dizzy. If you want to do a starter you need to feed the yeast. There is no food left in the saved yeast cake.

 

[IslandLizard]

Those look like pint jars, which means you have a maximum of 2 oz thick slurry each, 4 oz total. From my experience that's plenty for your 1.057 beer as long as you aerate well. Let the wort splash nicely into your fermentor. Then shake well or, if you ferment in a bucket, whip it up like crazy with a large whisk for a minute.

Or make a vitality starter a la Brulosophy, which is what I would do.

Definitely decant that old oxidized beer as much as you can.

 

[brew703]

Those look like pint jars, which means you have a maximum of 2 oz thick slurry each, 4 oz total. From my experience that's plenty for your 1.057 beer as long as you aerate well. Let the wort splash nicely into your fermentor. Then shake well or, if you ferment in a bucket, whip it up like crazy with a large whisk for a minute.

Or make a vitality starter a la Brulosophy, which is what I would do.

Definitely decant that old oxidized beer as much as you can.

Here's what I did:
took 600 ML of boiled wort from the batch I brewed on Friday. Cooled and pitched the decanted contents from both jars. Put on the stirplate for about 8 hrs then pitched. Took roughly 11 hrs for fermentation to start. This morning it is rolling with strong fermentation. We'll see how it turns out but so far it appears promising.

 

[Morrey]

I think you took the best approach meaning better safe than sorry. With the yeast getting some age on it, doing a quick starter was certainly in your best interest as insurance! Kudos!!