Maximizing Yeast Count for 10 gallon lager

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joety

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Howdy folks

I'm going to be brewing a 10 gallon lager next weekend and am working on the yeast starter(s) this weekend. In the past, I've either done a 5 gallon batch (5 qt starter, decanted the night before after stepping up once using a stir plate) or I used four packs of dry lager yeast in a 10 gallon batch. This time I want to use Wyeast 2308 Munich Lager. I will ferment in a temperature controlled garage in the dead of Wisconsin winter, likely around 50 degrees ambient. I haven't written the recipe yet, but I'll use Belgian Pilsner as a base and shoot for a 1.050 gravity beer.

I will be testing out my new chiller setup. I was utilizing a standard CFC setup with our tap water around 60 degrees. This, of course, limits the low end of the wort to the low 60's. The new setup will have a second heat exchanger which recirculates water out of an ice filled sump, to pre-chill the tap water. I can't wait to see how well it works.

Anyway, reason for my post. I want maximize my yeast cell count since I suspect I may end up on the low side given equipment limitations. This is what I have:
  • 2 packets of Wyeast 2308
  • 1 stir plate
  • 1 2 liter flask
  • 1 5 liter flask
  • plenty of quart jars of starter wort
  • 1 week before I brew

I contemplated the following:

  • combine both packets and 2 quarts of wort in the 2 liter flask and ferment on stir plate
  • transfer to the 5 liter flash and add 3-4 more quarts of wort and ferment
  • crash cool in the fridge the day before brew day
  • decant the morning of brew day

What say 'yeh experts?
 
I don't think you need 2 packs of yeast. Check out this calculator: http://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

I think you can easily work with 1.5 L of 10 Plato wort for the first step and 3 L 10 Plato wort for the 2nd step.

Or one step with 4.5 L, but then you are not likely to get any vortex in the large flask.

Kai

Thanks, Kai

I do manage to pull a vortex yet with my 5L mostly full. I don't think I can pull it to the bottom, but I can get a decent one going.
 
If you want to delay it a couple weeks, just do a 2.5 gallon extract lager with one packet of yeast, an ounce of hops and youll end up with a case of beer and enough yeast to ferment 10 gallons. Im done with the time involved doing stepped starters and am not spending $20+ on liquid yeast. An abbreviated boil with $10 of extract and an ounce of hops is easily accomplished on the stovetop and aside from cooling the wort, takes little more time than i'd spend making a starter.
 
For 10 gallons of a lager you're looking at about 700 billion cells. With two packs of yeast that means 500 billion growth. 10°P x 4.5L x 10 = 450 billion. Looks solid to me. Without a stir plate growth seems to be about 1 billion cells per gram of extract consumed. It's more with a stir plate, but I don't have a number. If the driving factor is ATP production by aerobic respiration vs anaerobic respiration then it could be as high as 10 billion cells per gram of extract consumed.
 
Any thread Kai posts in becomes awesome by definition. I love it!

Thanks.

Woodlandbrew,

When using a foil covered starter on a stir plate have observed a growth of about 1.4 Billion cells per gram of extract. Because all yeast cells have equal access to the nutrients, and possibly more available O2, stirred starters behave differently than still starters when it comes to yeast growth. Because of that one can't easily apply growth behavior observed in still starters to the growth behavior in stirred starters. You may have already seen this but others may want to take a look at this blog post http://braukaiser.com/blog/blog/2012/11/03/estimating-yeast-growth/ where I outline my current take on yeast growth.

I'll be talking about this at the NHC in Philly, so there will be much more to come on this front.

Kai
 
When using a foil covered starter on a stir plate have observed a growth of about 1.4 Billion cells per gram of extract.
Is that per gram of initial extract, or consumed extract?
take a look at this blog post http://braukaiser.com/blog/blog/2012/11/03/estimating-yeast-growth/ where I outline my current take on yeast growth.
That's a wonderful piece that you did!
I'll be talking about this at the NHC in Philly, so there will be much more to come on this front.
I think it's awesome that someone with your knowledge is so willing to freely discuss sometimes even the simplest points with the homebrew community here on HBT.
 
Is that per gram of initial extract, or consumed extract?

That's a wonderful piece that you did!

I think it's awesome that someone with your knowledge is so willing to freely discuss sometimes even the simplest points with the homebrew community here on HBT.

Agree with all points! Keep the discussion here, really interested in the results.

Woodlandbrew, I've been following your blog since December. Your efforts and experiments are greatly appreciated.

Kaiser, any idea when you will be speaking at the conference? I can't make the weekend but hope to be there Wed and Thursday.
 
Is that per gram of initial extract, or consumed extract?
It’s per gram of initial brewer’s extract (I.e. all malt wort). I know that not all of it will be consumed and that the actual attenuation and wort composition can affect yeast growth. However, I believe that these variances are smaller than the accuracy of yeast counts and that it will be in the noise. In the end we are looking for a way to estimate yeast growth based on what we put the yeast into and don’t want to make a guess regarding the attenuation that we expect. Most brewers are using DME and I will start using this too. So far I have worked with leftover wort from brew sessions.

I have done some calculations based on theoretical yeast growth numbers and that resulted in 1.3 B cells per gram of extract. But I have to scrub these calculations first since it could be just coincident that it is close to the 1.4 B/g that I commonly observe. I have also observed growth numbers as high as 1.9 B/g which is something else I need to look into. But that’s what I built the 2 double stir plates and the incubator for so I can run 4 tests in parallel.

I think it's awesome that someone with your knowledge is so willing to freely discuss sometimes even the simplest points with the homebrew community here on HBT.

Thanks. sometimes the simplest points are the most intriguing from a scientific point of view.

Kaiser, any idea when you will be speaking at the conference? I can't make the weekend but hope to be there Wed and Thursday.

I checked and they have not released a schedule yet. With my luck it will be 9 AM after club night.

Kai
 
Brewday was a success. I ended up doing a step up from 2 quarts, decant, then 5 more quarts. I don't have any way to count the yeast, but volume wise it looked pretty good. The ice sump pre-chiller worked great. I have one carboy at 54 degrees, the other at 56. I could have easily gone down another ten degrees if needed. The garage is at 52 degrees. I have the thermostat set to kick in at 50 if it gets colder.

Ice Sump.JPG


Yeast.JPG


Carboy 1.JPG


Carboy 2.JPG


All Done.JPG
 
More interested in your setup than the yeast count:)

Nice.

Sure thing, it's a 10 gallon RIMS system controlled by a panel modeled after Kal's Electric Brewery, except mine is primarily NG. You can see the 1 inch gas line coming down the wall on the right. The control panel does not control the gas valves. On the left you will see my Stout Tanks Conical, which I would be using if I wasn't fermenting a lager in the garage (the garage has heating coils in the floor making it perfect for doing lagers in the winter). Above the setup is a 6x4 commercial exhaust hood that I found at a scrap yard, complete with grease traps and halogen lights. Above that you can see the 8 inch exhaust line connected to the 747 cfm Inline Fan in the upper right corner. On the other side of the fan is short length of flexible air duct connect to styrofoam manifold which plugs into my basement window opening. The BK is 25 gallon, the other two vessels are 15. The MT has a false bottom and fly sparging is done the same way Kal does it with just hose laying on the grain bed. Kal uses SS quick disconnects for everything, but I opted for tri-clover fittings.

In included an up close picture which shows the bleeder valves on the pumps. They help, but it can still be a PITA to prime the pumps at times.

The next photo is my keezer. In addition to the Love Controller, I wired in a small computer fan which kicks on when the compressor runs. I put it in for better temperature control, but I have found it stays much drier than my old keezer that gave up the ghost a couple years ago.

Finally I added a photo of my other favorite beverage. The rack is two bottles deep and can hold 256 bottles; more if you double stack them on the top shelf.

Setup1.JPG


Up Close.JPG


Keezer.JPG


wine rack.JPG
 
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