Chris White on Starters

lshaner said:

And yet another factor that plays into the calculations is the amount of cells you start with in your starter. White's observations about less new cell growth in a small starter pitched with a large amount of yeast is accurate. Here is my analogy for that situation. Imagine you need to eat three Twinkies to create a new you. If you're dropped into a room with 12 Twinkies, the prediction is that you can generate 4 new yous for a total of 5. What happens when 12 of you are dropped into a room with 12 Twinkies? If all of you quickly eat a Twinkie, there aren't enough Twinkies to make any new yous, so you remain at 12, despite the consumption of the available nutrients.

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I love this! But why did you use twinkies? This is a beer forum, why not use beers? "If you are dropped in a room with a case of beer..."

lshaner said:

There's definitely a discrepancy between the pitch rate calculators available to home brewers. Interestingly, I think a lot of the discrepancy comes down to the strains chosen to generate the underlying data. At Omega Yeast, we've undertaken a project to determine the terminal cell density every strain in our collection can achieve under the same conditions in order to provide a strain-specific pitch rate calculator. This might not be immediately apparent to most people, but every yeast strain is capable of growing to a different terminal cell density in the same medium. For example, when started from cells scraped off a plate, the Chico strain (WY1056/WLP001) has achieved cell densities of 148 million cells per mL, which is less than Kai's pitch rate calculator would predict (168 million cells per mL). Some strains, like WY1318, only get to 130 million cells per mL under the same conditions. Some Belgian strains, however, can achieve up to 300 million cells per mL. And Brett upwards of 600-900 million cells per mL. Note that Kai only used WY2042 when generating his data. His numbers for that strain are on par with what we've seen with that strain.

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Great post! That's the info I was looking for.

Weezy said:

Starters are a great way to prove your yeast and get them invigorated for the job (we can argue til the end of days on what an appropriate cell count is for a given beer).

I do 3 gallon batches. If I use liquid yeast, which would have more than enough yeast in a vial, I'll do a 300 ml starter just to get them awake and engines running. If no activity, it was a bad vial (and its happened).

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This. Exactly this.
I've pitched vials of bad yeast into wort and had no/very little activity, which led to having to buy more yeast to pitch in after the wort has been sitting lifeless for 7 days. Since I've been making starters I can prove my yeast before brew day and know that I'm pitching healthy yeast (regardless of the numbers) into my precious wort.

Cyclman said:

I would think yeast would be thrilled to grow at 80 degrees. Yes, you'd have lots of esters, you wouldn't want to pitch the starter liquid into your beer for that reason, but if you crash and decant, I would expect this to grow yeast quickly.

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Some are thrilled. When I grow most ale strains up on plates I just throw them into a 30C incubator to get them grown up faster. I'll incubate at the low end of their growth range if I'm trying to separate yeast from some other bug.

I think that the main issue at play is that your average home brewer doesn't have a good grip on yeast biology, and all have varying goals for their beers. The advice given then has to be as broad and simple as possible. Telling people to direct pitch one vial of fresh WLP into 5 gallons of 1.050 wort is exactly that.

That advice though sucks for certain goals just the same as the advice that homebrewers who say to use .75-1 million cells/ml/plato sucks for specific goals.

The one thing I will say is that I highly prefer pitching starters that are at high krausen to pitching vials, smack packs, dry yeast, or cold crashed starters. They take off faster and just seem to give better results.

EDIT: and as a background, I don't buy yeast generally, I build up from plates or from top-cropped yeast depending on what is convenient.

AK7007 said:

Some are thrilled. When I grow most ale strains up on plates I just throw them into a 30C incubator to get them grown up faster. I'll incubate at the low end of their growth range if I'm trying to separate yeast from some other bug.

I think that the main issue at play is that your average home brewer doesn't have a good grip on yeast biology, and all have varying goals for their beers. The advice given then has to be as broad and simple as possible. Telling people to direct pitch one vial of fresh WLP into 5 gallons of 1.050 wort is exactly that.

That advice though sucks for certain goals just the same as the advice that homebrewers who say to use .75-1 million cells/ml/plato sucks for specific goals.

The one thing I will say is that I highly prefer pitching starters that are at high krausen to pitching vials, smack packs, dry yeast, or cold crashed starters. They take off faster and just seem to give better results.

EDIT: and as a background, I don't buy yeast generally, I build up from plates or from top-cropped yeast depending on what is convenient.

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I definitely agree with you. especially happy to hear your comment on pitching starters at high krausen - this has been my best strategy as well and the one that makes most sense.

I do agree that yeast biology is not well understood. Not just by average home brewer - I think there's a lot of mystery even to guys like Chris White. Just too much variance and too many parameters to control.

However, while I am not Chris White and I don't speak for him but I will try offer my best theory of the original comments that started this thread:

Look at history of home brewing. 10, 20 years ago yeast and brewing was even more of a mystery, and a lot of people under-pitched old, barely-viable yeast, and while they made beer, sometimes even great beer, beer taste suffered tremendously as a result.

So homebrewers got all wise or paranoid even about proper yeast count and starters and all that. In fact, the advanced homebrewers got anal about yeast count, and super-anal about starter procedure.

But now fast-forward to 2015 when we have much cleaner, healthier strains, and globalization provides for faster, cheaper shipping, home-brew market expands tremendously and so you can get a vial of fresh yeast for about $7 at most LHBS, right now. But is it possible that the homebrewing is still stuck in 1990ies mentality?

Setting aside "big" bears (>1.065 or so), getting exact cell count and having a starter of "just" the "right" size, down to 5% margins, may be an overkill now.

It may be heresy to argue this here, but what if you could pitch a single, recently purchased vial into your wort and get identical (as far as blind taste are concerned) results to complex series of harvesting yeast, making starters etc.

Worse, for newbie brewers, making the starter is another tedious, time-involved step full of complex instructions, making things needlessly complicated and raising the entry barrier, and it could produce bad results, or worse, an infection.

Don't get me wrong - I DO harvest my own yeast, I have 6 or so vials and about the same amount of mason jars in my fridge right now, and I am about to do it again on the new yeast from a batch that is fermenting now, but I often wonder why I do it - is it really just to save $6.99? Is it just to prove that I am an "expert" of some sort? Why?

Is my yeast going to be cleaner than what pros can produce? Probably no.
Is saving $7 per batch going to make me so much richer by the end of the year? No.
Mostly it's experimentation and learning and trying things, but if in the process I am compromising my beer, why do it?

I have to admit, while there are historic reasons for why we all are still doing this and perhaps some macho thing about going through the entire process without getting it wrong in some dramatic fashion (look at "does this look infected to you?" threads), but in the end I wonder if this is all a major overkill, and maybe this is what Chris White is trying to communicate.

I am sorry but making and growing a starter (way ahead of time), monitoring progress, swirling/stirplating, cold crashing, properly decanting, storing, feeding etc. - is a major enterprise. It's almost as involved as making extract beer, just at smaller scale.

If Chris White tells me I can pay $7 to skip this entire sequence of steps that only introduces more risk to my yeast pitching process, I am IN! Hell, if I am brewing a big beer and I can buy two vials of high quality yeast for $14 and know that this saves me a week of growing the starter and worrying about the infection, I am still in. It's still a great deal! How much is your time and effort worth? What if I told you that your imperfect starter practice gives you 10% chance of infection vs. using the vial gives you only 1% of infection. The numbers are made up but are you rationally making the decision to harvest and propagate and make your own yeast, vs. well, just spending $6.99 or wherever it cost.

I suspect that perhaps in 10 years or so the whole "harvest your own yeast" and "start your starter" culture will be diminished to the margins. Most people will talk about huge variety of yeast strains and grains, but not about some complicated procedures that will save you a few bucks but will do nothing for your beer.

tagz said:

You're right. I guess he does have data out there. It just doesn't seem, from my unscientific eye to mesh with Kai and Woodlands info.

Anyway, to keep the discussion going , here's the quote from the Basic Brewing episode: "It doesn't really generate a lot of new cells, in most people's starters, unless you are doing a fairly big one."

He also kind of scoffs at online yeast calculators, saying that they overestimate.

Here's Neva Parker's slide on yeast growth from her Myth Buster presentation.

View attachment 294487

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I don't get it. from looking the table image you attached it seemed like 2L starter goes from 25 to 84 or so in 48Hrs. That's a tripling of the cell count. Whether or not it is helpful is another argument, but any time you can increase something by a factor of 3.3, it should not be discounted easily. And I speak from personal experience.

55x11 said:

I do agree that yeast biology is not well understood. Not just by average home brewer - I think there's a lot of mystery even to guys like Chris White. Just too much variance and too many parameters to control.

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True, but hopefully White Labs follows through on some of their promises to publish genome data on all their strains, and we can predict much of this ahead of time. Our predictions won't be perfect, but they will guide us a lot better than the current guesswork.

55x11 said:

Is my yeast going to be cleaner than what pros can produce? Probably no.

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Don't sell yourself short - the pros still sell us contaminated stuff. It's not easy doing what they do without antibiotics. They are pretty awesome, but not perfect or anything.

55x11 said:

I am sorry but making and growing a starter (way ahead of time), monitoring progress, swirling/stirplating, cold crashing, properly decanting, storing, feeding etc. - is a major enterprise. It's almost as involved as making extract beer, just at smaller scale.

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It's actually more time consuming than extract beer to grow up from plates like I do, and I'm not actually saving money doing it (about break-even actually) - but I guess I do it because I can. I should probably start buying more yeast. I refuse for certain things though - I'll be damned if I'm gonna buy a bunch of Brett for example.

AK7007 said:

True, but hopefully White Labs follows through on some of their promises to publish genome data on all their strains, and we can predict much of this ahead of time. Our predictions won't be perfect, but they will guide us a lot better than the current guesswork.



Don't sell yourself short - the pros still sell us contaminated stuff. It's not easy doing what they do without antibiotics. They are pretty awesome, but not perfect or anything.

It's actually more time consuming than extract beer to grow up from plates like I do, and I'm not actually saving money doing it (about break-even actually) - but I guess I do it because I can. I should probably start buying more yeast. I refuse for certain things though - I'll be damned if I'm gonna buy a bunch of Brett for example.

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So you are picking out specific strains that you want and propagating those? That sounds pretty professional, what sort of equipment do you use for this, and what is the process for doing this?

AK7007 said:

True, but hopefully White Labs follows through on some of their promises to publish genome data on all their strains, and we can predict much of this ahead of time. Our predictions won't be perfect, but they will guide us a lot better than the current guesswork.

Don't sell yourself short - the pros still sell us contaminated stuff. It's not easy doing what they do without antibiotics. They are pretty awesome, but not perfect or anything.
It's actually more time consuming than extract beer to grow up from plates like I do, and I'm not actually saving money doing it (about break-even actually) - but I guess I do it because I can. I should probably start buying more yeast. I refuse for certain things though - I'll be damned if I'm gonna buy a bunch of Brett for example.

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As I re-read my own post, it comes off a bit harsh - I think many of us have a lot of fun experimenting with yeast harvesting, starters etc. Including myself. What you do is a step above that, and as a scientist (not a biologist but married to one), I definitely approve and salute you, kudos to you and all that. It's human nature to experiment and tinker with stuff.

It is similar to - if you are mechanically inclined, to fix your own lawnmowers and cars and bikes, even if it's not cost-effective, because it gives you knowledge and pleasure. Or perhaps paint your own walls and do your own landscaping and plumbing, because once again, perhaps it is fun for you. But for a lot of people it is not.

I think "tinkering" is a perfect reason to do this, as long as one acknowledges it, and the whatever risks they take on. For some people risks are minimal, sure.

What I worry a little about is the message to newbie brewers that everyone MUST be harvesting and propagating and using starters. Just like everyone must be going all-grain. Except for all-grains a case could be made that process is fairly simple and risk-free and that having a higher degree of control can make your beer taste better. (and it saves you a factor of 3 or so in costs).

With harvesting and propagating the similar case is very weak. The risks are there, benefit to taste is minimal, and if money is no object (at the level of $7 a vial) a more reasonable strategy is to just buy vials and pitch them without using starters or harvesting. Priority-wise, harvesting my own yeast is very low on my list of improvements.

joshesmusica said:

So you are picking out specific strains that you want and propagating those? That sounds pretty professional, what sort of equipment do you use for this, and what is the process for doing this?

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I learned yeast management as a researcher, but this is a good DIY primer for somebody coming into it cold - it's easy enough, but be prepared to screw it up a few times before you consistently grow up yeast without contaminants: http://bootlegbiology.com/diy/isolating-yeast/

You don't need much to do it at home - plates (primer here:http://bootlegbiology.com/diy/creating-plates/ - glass plates are reusable), an alcohol burner, and an inoculation loop. Pressure cookers are nice to have as well for sterilizing things, but boiling, storage in ethanol, or UV light can work depending on the application.

I mostly isolate cultures that I get from commercial vials and keep frozen or on plates. I then build the culture up from single colonies the next time so I don't have to rebuy. It's basically what commercial labs do in the early steps before they put their yeast into big propagators. This presentation from Bell's gives an overview of how commercial labs generally propagate yeast: http://www.mbaa.com/districts/michigan/events/Documents/2011_01_14PracticalPropagation.pdf

I have also dabbled in isolating strains from fruit or my yard, but that was during a stretch when I was brewing almost exclusively IPAs, and the cultures I isolated weren't good for that. This little discussion is making me think though, maybe I should start doing it again to add to my house saison blend.

55x11 said:

What I worry a little about is the message to newbie brewers that everyone MUST be harvesting and propagating and using starters.

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I hope that nobody actually thinks that home yeast management is a must. It is not. I do however, see frequently when this topic comes up on reddit or wherever, the idea that you can't do these things at home, and why bother trying since yeast labs are good at it. I push back against that - you CAN manage your yeast at home, it just takes lots of practice and a willingness to make mistakes. For many, that isn't worth it. Which is fine, and there's no judgement either way. Both approaches work, buying everything vs doing everything yourself. Your analogies are spot on.

fwiw, good bad or indifferent, the "harvesting and re-pitching" aspect is interesting, but perhaps out-of-scope of the original question...

Cheers!

I use a starter every time, because I can't control how the yeast is handled on the way to the LHBS or by the employees of the LHBS. Even if I don't grow any more yeast, at least they are roused and ready to work.

lshaner said:

There's definitely a discrepancy between the pitch rate calculators available to home brewers. Interestingly, I think a lot of the discrepancy comes down to the strains chosen to generate the underlying data. At Omega Yeast, we've undertaken a project to determine the terminal cell density every strain in our collection can achieve under the same conditions in order to provide a strain-specific pitch rate calculator. This might not be immediately apparent to most people, but every yeast strain is capable of growing to a different terminal cell density in the same medium. For example, when started from cells scraped off a plate, the Chico strain (WY1056/WLP001) has achieved cell densities of 148 million cells per mL, which is less than Kai's pitch rate calculator would predict (168 million cells per mL). Some strains, like WY1318, only get to 130 million cells per mL under the same conditions. Some Belgian strains, however, can achieve up to 300 million cells per mL. And Brett upwards of 600-900 million cells per mL. Note that Kai only used WY2042 when generating his data. His numbers for that strain are on par with what we've seen with that strain.

And to complicate matters further, Kai has also shown that stir plate speed impacts cell density achieved by the same strain -- likely because higher stirring speed exposes the growing cells to more oxygen (http://braukaiser.com/blog/blog/2013/03/25/stir-speed-and-yeast-growth/). We've found his observations on stir plate speed to be accurate. Our numbers line up with his with the "medium" speed results he reports with WY2042.

And yet another factor that plays into the calculations is the amount of cells you start with in your starter. White's observations about less new cell growth in a small starter pitched with a large amount of yeast is accurate. Here is my analogy for that situation. Imagine you need to eat three Twinkies to create a new you. If you're dropped into a room with 12 Twinkies, the prediction is that you can generate 4 new yous for a total of 5. What happens when 12 of you are dropped into a room with 12 Twinkies? If all of you quickly eat a Twinkie, there aren't enough Twinkies to make any new yous, so you remain at 12, despite the consumption of the available nutrients.

So all told, things are a little more complicated than they initially appear given strain to strain variations, stir plate speed, and starting cell density. We've found that for some strains, Kai's calculator does in fact underestimate the cell count and for others, it overestimates.

This goes to show that there's a lot of wiggle room in getting good results when it comes to pitch rate. I generally favor starters for the reasons a lot of people have already stated in this thread -- you know your yeast is viable when you see an active starter and the lag time is shorter, giving any baddies present less chance to cause problems. That said, we're going to make all of our data publicly available when we have it. Our hope is to offer a strain specific pitch rate calculator that incorporates the data we generate for those who wish to get a little more precision in pitch rates, for what it's worth.

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Thinking out loud here, if you were to add the expected attenuation of the yeast strain ( low end ) to the formula for the propagation rate, the accuracy of the yeast pitch rate calculator should be more accurate, as long as the attenuation rates are known, regardless of the strain and manufacturer. It could be a simple lookup table populated from the various yeast manufacturers published data versus Kai's data, as a base line.