Enough yeast for a 24 Bbl fermentation

[Rachmsimp]

I have a bit of a dilemma... I just got hired as a lab tech in a brewery with a background in biology but I have no large scale production experience in brewing. I'm unsure how to grow up enough yeast for a 24 bbl system, but I have some ideas. My plan for one of our ales is to make 4 separate 2L starters with 1 vial of white labs liquid yeast each, (~100 billion cells) letting those propagate for 12-18 hours, then pitching these into a larger vessel (the largest vessel we have that isn't a fermenter is 45L, is this okay?) letting that propagate and aerate and then pitch it into our 24 bbl system. With an OG of 1.038 my final cell count needs to be some 20 trillion cells. Is there anyway to know how much these will multiply? Will I be underpitching with this method? HELP!

Thank you!

[revolutioned]

yeast

1. We make a two liter starter from one vile of white labs and let it sit for 24 hours.

2. We then make 5 gallons of wort from DME cool and pump into a 1/2 barrel keg with a brew hardware fermentation conversion cap.

3. After 24 hours we make another 5 gallons of DME wort and pitch it into the keg and let that sit for 24 hours.

This method usually gets us enough for a 30 bbl batch. I hope this helps you out.

[OneMoreBrewer]

I'm don't have a biology degree, but aim positive you are Better off growing a single culture out, rather than growing four cultures and throwing them together. Come on man! Kidding. Build the culture up, ideally from a single ideal cell, but that's a little more difficult. Keep your yeast at high krausen so they are replicating well and add more low gravity wort. Be sterile for god sakes! Please someone correct me if I'm a little off, I'm no expert.
Count your cells on a measured slide(has a volume and grid), and then multiply to get cell count. Take samples as you build and you will know the cells to volume ratio from the cell counts. When you get enough cells, pitch the yeast. Don't forget about viability calculations. Yeast need oxygen and agitation to reproduce well. Good luck.

[Tubbybrew]

1. We make a two liter starter from one vile of white labs and let it sit for 24 hours.

2. We then make 5 gallons of wort from DME cool and pump into a 1/2 barrel keg with a brew hardware fermentation conversion cap.

3. After 24 hours we make another 5 gallons of DME wort and pitch it into the keg and let that sit for 24 hours.

This method usually gets us enough for a 30 bbl batch. I hope this helps you out.

I know this thread is a couple years old at this point but I was wondering if you did any cell counts to confirm that your method was producing enough cells for your needs or if you were just guessing based on performance. I ran your process through a couple of different starter calculators and it seems that this process wouldn't be adequate for even a 10 bbl batch. Are you contiguously oxygenating during each of those 24 hours incubations?

I would be ecstatic if such a simple process produced enough cells for a pitch rate of 0.75M/ml/P

Cheers!
- Chris