Yeast Starter for 31.5 gal... how big?

[letsbrew]

Hello, i need to make a starter for 31.5 gal i see in brewersfriend dot com that if i use 1 smack pack of 11.5grams of dry yeast, this amount will allow me to start with 230 billions cells (if as daniels says that dry yeats comes with 20 billions cells per gram of dry yeast)

So with an initial 230 billion cells and according to wyeast that says that a starter must be at least 10% de size of your fermenting wort i assume that i have to use a starter of 3.15gal with 1 dry smack pack of 11.5gr.

By doing the calculation on that website it shows me that i will end up with 2147 billions cells more than enough to ferment the 31.5gallons.

But what do you think? will be enough dry yeast? will be too much gallons for the starter? Have you ever used that yeast starter calculator?


Regards!

 

[pabloj13]

A lot of people on here use MrMalty or Yeastcalc. What is your OG? I wouldn't waste your time making a starter with dry yeast. Why not just pitch 5 packets? That seems way easier than making a 3 gallon starter.

 

[stratslinger]

You're missing one important bit of information to figure out the starter size: your Original Gravity! Yes, volume plays a large role, but Original Gravity is equally as important.

Playing around with yeastcalc.com, if I figure on a 31.5 gallon batch size of 1.040 beer, it says I need 893 billion cells. Step that up to a 1.060 beer though, and it becomes 1318 billion cells. And those two numbers require very differently sized starters.

Also, using yeastcalc.com, you can easily change your starting cell count from 100 billion (common for liquid strains) to 230 billion (the number you're figuring for a dry strain). To get a single packet up to the right number of cells though, I'm thinking you'll want to go through a couple of steps to avoid stressing out the yeast. Yeastcalc.com will also allow you to play around with stepped starters.

 

[letsbrew]

A lot of people on here use MrMalty or Yeastcalc. What is your OG? I wouldn't waste your time making a starter with dry yeast. Why not just pitch 5 packets? That seems way easier than making a 3 gallon starter.

My SG is 1.063 i have used mrmalty but just give me the size for starter with liquid yeast. I know its easier to use 5-6 packets of dry yeast but to get the yeast is expensive here in Mexico even by buying directly from US. Thats why i plan to make starters with dry yeast.

I will use a corny keg to make the starter and push it to the FV.

 

[pabloj13]

My SG is 1.063 i have used mrmalty but just give me the size for starter with liquid yeast. I know its easier to use 5-6 packets of dry yeast but to get the yeast is expensive here in Mexico even by buying directly from US. Thats why i plan to make starters with dry yeast.

I will use a corny keg to make the starter and push it to the FV.

Gotcha. MrMalty has a dry yeast tab too, FYI

 

[tre9er]

You'd need 6.6 packs of 11.5g dry yeast for this beer. So, if you don't have that many and need to step up starters, here's the plan:

Do a 23L starter, on a stir-plate, with a starting OG of 1.037. That's 80 oz. of DME.

If you don't have a stir-plate, you need to do a 35L starter and agitate it frequently as you can.

Or you can step up a starter on a stir-plate by doing a 5L then a 6L, or a 3L and a 7L.

No stir-plate step up: 6L, 9L

 

[tre9er]

Basically without a stir-plate you need to brew a 9g batch of beer and then use that yeast cake for the 31.5G batch.

 

[Bierliebhaber]

Just make a 5g batch first and pitch the yeast cake. Should be good. But I don't see how 5 packs of dry yeast could be more expensive than a 20 liters of beer. Then again, you have the beer to show for it.

 

[pabloj13]

Do a 23L starter, on a stir-plate, with a starting OG of 1.037. That's 80g. of DME.

Does not compute.

 

[letsbrew]

Gotcha. MrMalty has a dry yeast tab too, FYI

hehehe yep but expensive for me for 1 pack i pay 5-10 bucks

 

[letsbrew]

You're missing one important bit of information to figure out the starter size: your Original Gravity! Yes, volume plays a large role, but Original Gravity is equally as important.

Playing around with yeastcalc.com, if I figure on a 31.5 gallon batch size of 1.040 beer, it says I need 893 billion cells. Step that up to a 1.060 beer though, and it becomes 1318 billion cells. And those two numbers require very differently sized starters.

Also, using yeastcalc.com, you can easily change your starting cell count from 100 billion (common for liquid strains) to 230 billion (the number you're figuring for a dry strain). To get a single packet up to the right number of cells though, I'm thinking you'll want to go through a couple of steps to avoid stressing out the yeast. Yeastcalc.com will also allow you to play around with stepped starters.

yes i forgot that my sg is 1.063

 

[letsbrew]

Basically without a stir-plate you need to brew a 9g batch of beer and then use that yeast cake for the 31.5G batch.

Thanks! i have a inlet oxygen stone with a O2 tank and sterile filter on it i guess i will get good ppm of oxygen this must help

 

[letsbrew]

Just make a 5g batch first and pitch the yeast cake. Should be good. But I don't see how 5 packs of dry yeast could be more expensive than a 20 liters of beer. Then again, you have the beer to show for it.

yeah quite dificult but i pay 5-10 dollars for 1 pack of dry yeast and for DME im using a local DME that cost me less than that for kg thats why im focus on this idea

 

[WoodlandBrew]

Dry yeast packages might have up to 20 billion cells per gram. That's the dry weight of yeast. However all of the dry yeast I have counted has about 15 billion cells per gram likely because some of that weight is nutrients. Also, viability will not be 100%, and is largely driven by how the yeast is hydrated.
details here:
http://woodlandbrew.blogspot.com/2013/02/rehydrating-safbrew-yeast.html

Also the popular starter calculators can be way off. Especially when it comes to using a stir plate. Although I don't think I have ever seen a stir plate that could stir 23 litters. They are also way off when it comes to low inoculation rates and or high volumes.

You need to grow about 800 billion cells. 1 pack of yeast with 800g of DME in 8 litters should get you there in two or three days. Or just buy 6 packets of yeast.

Another way to do it is to use part of your beer wort as the starter. Essentially scale your beer down to a volume that 150 billion cells (one package) would be adequate. After a day or two, add the rest of the wort, as you would with the "no-chill" method.

details here:
http://woodlandbrew.blogspot.com/2012/12/no-more-wasteful-yeast-starters.html

 

[beeber]

I generally try to step up on a 1-to-10 proportion. So for 31 gal you'd want about a 3.1 gallon starter.

 

[stratslinger]

Well, going by those figures, if you did a 1.5 gallon starter, then cold crashed it and pitched the slurry into a 2.25 gallon starter, frequently shaking the starter at both stages, you'd have enough yeast to pitch to a 31.5 gallon batch.

But you're talking 560g of DME for the first step of the starter, and another 840g for the second step. That's just about a 3lb bag of DME - which costs around $12 without shipping up here in the US (not sure what you'd pay locally for DME), and you're probably looking at 1-2 weeks total time for the starter to process through both steps... Are you certain that the DME and the time you'll spend doing this starter is really less expensive than the extra packets of yeast, both in dollars and in time?

 

[tre9er]

Does not compute.

?? AHA, OZ, not G...yep!

Make a starter with 1.037 OG and put it on a stir plate. It would take 80 ounces of DME to make such a starter at 23L

 

[tre9er]

Thanks! i have a inlet oxygen stone with a O2 tank and sterile filter on it i guess i will get good ppm of oxygen this must help

With O2 injection you'll need a larger starter if you don't step it up. You'd basically need to make a 10g starter, or 10g batch of beer (which makes much more sense), although you'd be underpitching in that...

I would step up the yeast by making a 5g batch of beer, low-to-mid gravity, and then pitch a 5g batch onto that cake. You could turn that around in under 3 weeks if the beers were basic and you control pitch/ferm temps closely.

 

[pabloj13]

?? AHA, OZ, not G...yep!

Make a starter with 1.037 OG and put it on a stir plate. It would take 80 ounces of DME to make such a starter at 23L

Ahhh, that makes more sense. You said 80g. I got it.

 

[tre9er]

Also the popular starter calculators can be way off. Especially when it comes to using a stir plate. Although I don't think I have ever seen a stir plate that could stir 23 litters. They are also way off when it comes to low inoculation rates and or high volumes.

You need to grow about 800 billion cells. 1 pack of yeast with 800g of DME in 8 litters should get you there in two or three days. Or just buy 6 packets of yeast.

Another way to do it is to use part of your beer wort as the starter. Essentially scale your beer down to a volume that 150 billion cells (one package) would be adequate. After a day or two, add the rest of the wort, as you would with the "no-chill" method.

details here:
http://woodlandbrew.blogspot.com/2012/12/no-more-wasteful-yeast-starters.html

Just read a bunch of your blog. Excellent stuff. I've always had great "luck" with whole harvested cakes, even months old, and your data seems to support this. I wonder if you found more info on overall yeast health over time vs. simply the number of living cells remaining?

I also wondered about determining the cell counts in a given slurry, ie. the non-yeast %, have you found a good way to estimate this?

 

[WoodlandBrew]

Just read a bunch of your blog. Excellent stuff. I've always had great "luck" with whole harvested cakes, even months old, and your data seems to support this. I wonder if you found more info on overall yeast health over time vs. simply the number of living cells remaining?

I also wondered about determining the cell counts in a given slurry, ie. the non-yeast %, have you found a good way to estimate this?

Recently I did a 42 vial matrix fermentation test of fresh and month old yeast. Im still reviewing the data, but so far the results are surprising. I also revived a culture that was 4 month old and the fermentation metrics were fine.

The easiest way to get an estimate of cells is a slurry is by measuring the thick slurry volume. Assuming 1 billion cells per milliliter will get you in the ball park.

 

[stratslinger]

Also the popular starter calculators can be way off. Especially when it comes to using a stir plate. Although I don't think I have ever seen a stir plate that could stir 23 litters. They are also way off when it comes to low inoculation rates and or high volumes.

You need to grow about 800 billion cells. 1 pack of yeast with 800g of DME in 8 litters should get you there in two or three days. Or just buy 6 packets of yeast.

I'm curious as to where you're getting your data from to make your first assertion, since both of the popular starter calculators are based on some widely accepted literature on the topic? I'll grant that most of that research is geared towards those of us who are working more in the 5-10 gallon range - do the innoculation rates really vary that much when the volume increases a bit?

Also, the math in your second statement doesn't hold up, so I'm a bit confused there. If OP only needs 800 billion cells, why would he need 6 packets of yeast as a starter alternative, when each packet of yeast should contain roughly 230 billion cells? Wouldn't 6 packets be back into the same cell count as those calculators you're telling OP to disregard?

 

[WoodlandBrew]

I'm curious as to where you're getting your data from to make your first assertion,

I'm glad you asked. It's from what people who have actually counted cells generated from a starter have observed. Also, I've done quite a few cell counts myself. Here is my most recent findings:
http://woodlandbrew.blogspot.com/2013/01/starter-cell-growth.html

since both of the popular starter calculators are based on some widely accepted literature on the topic?

Actually, the two most popular calculators are based on each other which is why they match so well. Yeast calc is a direct derivative of Mr. Malty. I emailed the author and he confirmed this. If you run it up against Wyeast calculate, or Kai's calculator on Brewes Friend you will see that everyone has a little different idea on how things work.
http://www.wyeastlab.com/hb_pitchrate.cfm
http://www.brewersfriend.com/yeast-pitch-rate-and-starter-calculator/

The calculators are popular because they are easy to use which has lead to being well publicized. If by "widely accepted literature" you are referring to "the yeast book," then I'll have to point out that the author of both Mr. Matly and Yeast is Jimal. Both are a just the same data from experiments done at White Labs. It's really all just one set of data.

I'll grant that most of that research is geared towards those of us who are working more in the 5-10 gallon range - do the innoculation rates really vary that much when the volume increases a bit?

It's cells per volume so when you double the volume and keep the number of cells the same the inoculation rate is half. The Mr. Malty / Yeast Calc formula drops off pretty quick bellow 65 million per ml. For comparison, a typical ale is pitched at 0.75 million per ml.

Also, the math in your second statement doesn't hold up, so I'm a bit confused there. If OP only needs 800 billion cells, why would he need 6 packets of yeast as a starter alternative, when each packet of yeast should contain roughly 230 billion cells? Wouldn't 6 packets be back into the same cell count as those calculators you're telling OP to disregard?

There are about 150 billion cells per package, and he needs about 900 billion total cells.

If the packages contained only yeast and they rehydrated to 100% viability there would be about 200 billion cells per package, but that is not the case. There is more than yeast in the package, and the viability is not going to be 100% My counts indicate 150 billion if careful rehydrated. See here:

http://woodlandbrew.blogspot.com/2013/02/rehydrating-safbrew-yeast.html

 

[tre9er]

The easiest way to get an estimate of cells is a slurry is by measuring the thick slurry volume. Assuming 1 billion cells per milliliter will get you in the ball park.

Yeah, that's what I generally do, but figuring out what's yeast and what's not can be difficult, as you showed in your Yeast Rinsing tests. I measure the slurry volume after it's settled for a good long while, weeks usually, sometimes more, so it's pretty compact at the bottom. I just don't know for sure what the non-yeast percentage is in the slurry.

 

[WoodlandBrew]

Yeah, that's what I generally do, but figuring out what's yeast and what's not can be difficult, as you showed in your Yeast Rinsing tests. I measure the slurry volume after it's settled for a good long while, weeks usually, sometimes more, so it's pretty compact at the bottom. I just don't know for sure what the non-yeast percentage is in the slurry.

The 1 million cells per ml has the non yeast percentage rolled in. In a clean slurry 2 million per ml is safe, but 3 is fairly common and 4 is not unheard of.

 

[letsbrew]

Dry yeast packages might have up to 20 billion cells per gram. That's the dry weight of yeast. However all of the dry yeast I have counted has about 15 billion cells per gram likely because some of that weight is nutrients. Also, viability will not be 100%, and is largely driven by how the yeast is hydrated.
details here:
http://woodlandbrew.blogspot.com/2013/02/rehydrating-safbrew-yeast.html

Also the popular starter calculators can be way off. Especially when it comes to using a stir plate. Although I don't think I have ever seen a stir plate that could stir 23 litters. They are also way off when it comes to low inoculation rates and or high volumes.

You need to grow about 800 billion cells. 1 pack of yeast with 800g of DME in 8 litters should get you there in two or three days. Or just buy 6 packets of yeast.

Another way to do it is to use part of your beer wort as the starter. Essentially scale your beer down to a volume that 150 billion cells (one package) would be adequate. After a day or two, add the rest of the wort, as you would with the "no-chill" method.

details here:
http://woodlandbrew.blogspot.com/2012/12/no-more-wasteful-yeast-starters.html

Really nice articles you have! this sounds good if i use just 800grm of DME here i get 1kg of DME in 3.7usd with shipping the dry yeast is the expensive thing, so in my pilot plant i could make the starter and let it work for 3 days in the corny. Maybe will be a good idea to install another small oxygen stone inside just on the inside of the keg

 

[letsbrew]

I generally try to step up on a 1-to-10 proportion. So for 31 gal you'd want about a 3.1 gallon starter.

3.15gal was what i was thinking same as you said

 

[WoodlandBrew]

1:10 is an old school brewing rule of thumb that holds quite a bit of merit. It fits right in with a couple of classic models. I'm working on a series of blog posts that tie it all together.

 

[letsbrew]

Well, going by those figures, if you did a 1.5 gallon starter, then cold crashed it and pitched the slurry into a 2.25 gallon starter, frequently shaking the starter at both stages, you'd have enough yeast to pitch to a 31.5 gallon batch.

But you're talking 560g of DME for the first step of the starter, and another 840g for the second step. That's just about a 3lb bag of DME - which costs around $12 without shipping up here in the US (not sure what you'd pay locally for DME), and you're probably looking at 1-2 weeks total time for the starter to process through both steps... Are you certain that the DME and the time you'll spend doing this starter is really less expensive than the extra packets of yeast, both in dollars and in time?

Thanks! by doing the step up thats defintely more work , that means for sure more work, what about let it work the 3gal starter for half week? i get the DME for 3.7usd 1kg including shipping and 2.9usd 1kg for liquid extract with shipping and if i use dry yeast i will spend 30usd or more because it doesnt inlclude shipping

 

[letsbrew]

With O2 injection you'll need a larger starter if you don't step it up. You'd basically need to make a 10g starter, or 10g batch of beer (which makes much more sense), although you'd be underpitching in that...

I would step up the yeast by making a 5g batch of beer, low-to-mid gravity, and then pitch a 5g batch onto that cake. You could turn that around in under 3 weeks if the beers were basic and you control pitch/ferm temps closely.

will reduce the time and size if i install inside of the keg an oxygen stone? to avoid shaking the corny....

 

[stratslinger]

Thanks! by doing the step up thats defintely more work , that means for sure more work, what about let it work the 3gal starter for half week? i get the DME for 3.7usd 1kg including shipping and 2.9usd 1kg for liquid extract with shipping and if i use dry yeast i will spend 30usd or more because it doesnt inlclude shipping

Well, here's the thing: doing the starter in 2 steps would generate significantly more growth than doing it all at once (seriously - just go and play around with the calculator at yeastcalc.com for about 20 minutes and you'll see for yourself).

But here's the other thing: going by woodlandbrew's figures, which seem a heckuva lot more reasonable and more easily attainable, it looks more like you could hit it with two steps of 1.25 gallons each, with 467g of DME in each starter. That'd leave you with a cell count of just a hair over 900 billion. For comparison, if you did just a single starter of 2.5 gallons, it'd only give you 653 billion cells.

If you could rig up your aeration stone for constant aeration the whole time the starter is going, you're closer to 1.1 gallon each step and 411g DME. If you had a stir plate big enough for the task, you could get down to .83 gallons each step (310g DME).

 

[atreid]

Just make a 5g batch first and pitch the yeast cake. Should be good. But I don't see how 5 packs of dry yeast could be more expensive than a 20 liters of beer. Then again, you have the beer to show for it.

A good starter is aerated whether it's from stir plate, intermittent shaking or constant O2. An oxygenated fermentation is no fermentation, it's propagation, so there's no "beer" to show for it.

If it's drinkable, it's not a good starter...

 

[Bierliebhaber]

a good starter is aerated whether it's from stir plate, intermittent shaking or constant o2. An oxygenated fermentation is no fermentation, it's propagation, so there's no "beer" to show for it.

If it's drinkable, it's not a good starter...

hahahahahahahahahahahahahahahahahahahahha

 

[atreid]

lol...

Kind of an oversized reaction to a simple truth... ;-)

 

[jbguzzi]

I think for that size batch, barring having the proper equipment, use an appropriate amount of dry yeast. I just recently discovered go-ferm which is a yeast nutrient designed for rehydrating the yeast. It worked great. I also used fermaid k in addition added in the lag phase and then after brew is about 2/3 done. Dry yeast is a lot better than it used to be. If it was me, all dry for that size. Good luck!