222 replies to this topic

[Brauer]

so you seem well versed in this stuff, what do you recommend for the average home brewer?

You're probably going to get slightly higher viability from a shaken culture than a stirred one, but I doubt very many homebrewers are going to have access to a shaker platform to perform continuous orbital shaking.

 

I'd doubt it's going to make much of a difference, if you pitch the same number of viable yeast, but it probably is a good argument for decanting the spent wort. I'd go with whatever gets you to the cell count you need (realizing that some calculators probably over-estimate the volume starter you need and the actual number needed is pretty forgiving). You're going to increase your cell number by something like 150 billion cells per Liter with a stirred starter and 90 billion cells per Liter from a periodically shaken starter.

 

I've made excellent beer with yeast pitched from a fermentation (an unstirred culture), from shaken cultures, and from stirred cultures. First, I'd ask, what problem are we trying to solve by not using stirred propagation? 

[SchwanzBrewer]

You're probably going to get slightly higher viability from a shaken culture than a stirred one, but I doubt very many homebrewers are going to have access to a shaker platform to perform continuous orbital shaking.

 

I'd doubt it's going to make much of a difference, if you pitch the same number of viable yeast, but it probably is a good argument for decanting the spent wort. I'd go with whatever gets you to the cell count you need (realizing that some calculators probably over-estimate the volume starter you need and the actual number needed is pretty forgiving). You're going to increase your cell number by something like 150 billion cells per Liter with a stirred starter and 90 billion cells per Liter from a periodically shaken starter.

 

I've made excellent beer with yeast pitched from a fermentation (an unstirred culture), from shaken cultures, and from stirred cultures. First, I'd ask, what problem are we trying to solve by not using stirred propagation? 

 

That's the crux of it. It could simplify things for homebrewers making 5 gallon batches for sure. It's tougher to determine the practicality and scalability of the process the larger the batch size.

[positiveContact]

You're probably going to get slightly higher viability from a shaken culture than a stirred one, but I doubt very many homebrewers are going to have access to a shaker platform to perform continuous orbital shaking.

 

I'd doubt it's going to make much of a difference, if you pitch the same number of viable yeast, but it probably is a good argument for decanting the spent wort. I'd go with whatever gets you to the cell count you need (realizing that some calculators probably over-estimate the volume starter you need and the actual number needed is pretty forgiving). You're going to increase your cell number by something like 150 billion cells per Liter with a stirred starter and 90 billion cells per Liter from a periodically shaken starter.

 

I've made excellent beer with yeast pitched from a fermentation (an unstirred culture), from shaken cultures, and from stirred cultures. First, I'd ask, what problem are we trying to solve by not using stirred propagation? 

 

I'm always looking to improve and I guess I never know exactly where that next little bit of even better is going to come from.

[Brauer]

I'm always looking to improve and I guess I never know exactly where that next little bit of even better is going to come from.

Intermittent shaking and a stirbar are both compromises that produce less than perfect results. The stirbar will stress the yeast with shear and intermittent shaking will stress the yeast with sub-optimal oxygen, elevated CO₂, and restricted exposure to nutrients. A lot of people stir in suboptimal conditions, though, such as using very full Erlenmeyer flasks. I usually use a shaken starter because that's all I need at my scale, but you'll need to make 1.7 L shaken for every 1 Liter of stirred, unless you want to also add the variable of pitching at 60%.  However, pitching rate is forgiving enough that you may not be able to tell the difference.

 

The proponents of this method are trying to duplicate the benefits of constant shaking without constant shaking. I don't think it is equivalent, but history shows that a periodically shaken beer will make excellent beer, so it should pass a taste test. I'll be interested to see a carefully controlled experiment, but I'll be surprised if they can tell how the yeast was propagated from the final beer.

 

There is another method, which should be better than shaking and that is more adaptable to homebrewing. That method uses an air pump to continuously aerate wort and help keep the wort moving, but slow enough to prevent foaming over.

[positiveContact]

what do you think of the daruflasdlfkjsdflksdjf method?  I know you'd probably never use it for your small batches.  What I don't get about it is how pitching something like a gallon of beer with a lot of yeast into 9 gallons of wort is going to end up.  won't that first gallon taste funny?

[Brauer]

I imagine it is just another starter like the others. The wort is just beer, no? I might worry about it if it was stirred and oxidized.

[positiveContact]

I imagine it is just another starter like the others. The wort is just beer, no? I might worry about it if it was stirred and oxidized.

 

it is but it's a pretty high percentage of the final product (10%ish).  that first gallon has been way over pitched if you were making beer (vs making a starter).

[Brauer]

To be clear, I don't think there's anything particularly wrong with a shaken starter, I just don't think that it's magic.

[denny]

To be clear, I don't think there's anything particularly wrong with a shaken starter, I just don't think that it's magic.

 

I tend to agree with you, but rather than surmise I decided to try it out.  We'll see....

[Brauer]

I tend to agree with you, but rather than surmise I decided to try it out.  We'll see....

Experimentation is what makes it science.  The original posts on AHA look like mostly theory.

[denny]

Experimentation is what makes it science.  The original posts on AHA look like mostly theory.

I know it's what Mark does, but I don't know if or how he's compared it to other methods. But my differences with him have alwyas been based in actual practice and results vs. theory.

[MyaCullen]

Isn't this the method advised by Whitelabs for propagating their yeast?

[denny]

Isn't this the method advised by Whitelabs for propagating their yeast?

 

Since I don't use Whitelabs, dunno.  Might very well be!

[positiveContact]

Since I don't use Whitelabs, dunno.  Might very well be!

 

do you have a relationship with wyeast?  I rarely use whitelabs but mainly b/c I'm more familiar with the wyeast.

[denny]

do you have a relationship with wyeast?  I rarely use whitelabs but mainly b/c I'm more familiar with the wyeast.

Kinda, but it's more becasue neither LHBS here sells White.  Not worth it to order it.

Just took a gravity reading.  In one week, it's gone from 1.063 to 1.013...pretty much exactly like when I pitched my "old style" starter.  I'm carbing and chilling a sample so I can taste it later today.

[positiveContact]

exciting!

[Brauer]

Just took a gravity reading. In one week, it's gone from 1.063 to 1.013...pretty much exactly like when I pitched my "old style" starter. I'm carbing and chilling a sample so I can taste it later today.

Do you really expect a difference? I seem to get the same final gravity from a repitch, a shaken or a stirred yeast starter, as long as it is healthy. If there is a difference, I would have only expected a subtle flavor difference.

[denny]

Do you really expect a difference? I seem to get the same final gravity from a repitch, a shaken or a stirred yeast starter, as long as it is healthy. If there is a difference, I would have only expected a subtle flavor difference.

 

Nope, I didn't expect a difference...just confirming to the doubters that there wasn't one!  My chilled, carbed sample was fantastic at one week after brewing.  It was cleaner and less estery than when I pitched more yeast.  so much for the "underpitch to increase esters" conventional wisdom.  I don't doubt that's true, but I do believe it's strain dependent.

[djinkc]

Nope, I didn't expect a difference...just confirming to the doubters that there wasn't one!  My chilled, carbed sample was fantastic at one week after brewing.  It was cleaner and less estery than when I pitched more yeast.  so much for the "underpitch to increase esters" conventional wisdom.  I don't doubt that's true, but I do believe it's strain dependent.

 

Did you pitch less volume than a usual stir plate starter?  I seem to be missing this.

[denny]

Did you pitch less volume than a usual stir plate starter?  I seem to be missing this.

 

Yep.  Maybe 1/2-1/3 as much.