Yeast Starters for Large Batches

[twilsonbrewpc]

How do pro breweries build yeast count? Do they use several stir plates? I know that doesn't seem likely. We are starting with a 2-bbl system doing double batches, so we will be fermenting 4 bbls. Plan is to pitch enough yeast for 4 bbls into the first batch and rack the second batch on top of the first. I use liquid yeast (White Labs) and will be repitching for several gens. I have never counted yeast before but I see the advantage of doing so and will likely do it in the near future.

Thanks in advance.

[kererubrewing]

For yeast counting and propagation you'll need a cell-counting chamber, a decent second-hand microscope with X/Y positioning (400x magnification), pippetor, some small lab ware, a set of Erlenmyer flasks (250ml, 500ml, 1L, 3L, and 5L), a Bunsen burner (alcohol lamps aren't hot enough), an orbital shaker (don't bother with a magnetic stir plate), a notebook and a calculator. Extras would be to have more flasks so you can run parallel propagations and a second orbital shaker. Also handy is a whiteboard, and a spreadsheet so you don't need to run the calculations every time.

You'll need a sterile supply of wort to culture with (I use a pressure cooker for this), or at least some hot-packed wort.

It's pretty quick work to count and propagate once you have some practice I with it and make sure you are using good, hygienic methods. There are lots of online tutorials on yeast propagation too. It's a great skill to have.

[Ted Briggs]

this may help

https://www.wyeastlab.com/pitch_rate.cfm

[KTY]

You should just order a pitch of yeast from one of the yeast companies. You could just go with a 2 bbl pitch, aerate and pitch you yeast on this batch and run the second batch ontop of the first 24 hours later while the yeast it is its growth cycle. This is called drauflassen and is common in many German breweries. I use it all the time going from a 10 bbl batch to triple batching in a 30 bbl fermentors. You will find that the beer attenuates a little more, and you get less ester development - so you may (or may not) want to make adjustments on your end to get the results you are looking for. You may also find that the fermentation times are drastically shorter.