[klickitat jim]

I'll bet that the U is not always symmetrical or the same for each yeast in every circumstance. So far I've not experienced the over pitch upright of the U. Not saying it doesn't exist. But with the yeasts I have over pitched, they were grossly over pitched and still rather bland. I used to try for super clean fermentation by way of low ester, till I realized that what i really wanted was eliminating off flavors and appropriate levels of esters.

considering how many things end up not being detectable via triangle test I have to wonder if a general guideline could work out in most cases but really I have no way to tell.  just a suspicion.

Generalizations work but only generally.  I have to agree with mark that one set pitching rate is not going to achieve the optimum effect for every strain or style.

[S. cerevisiae]

considering how many things end up not being detectable via triangle test I have to wonder if a general guideline could work out in most cases but really I have no way to tell.  just a suspicion.

You are not looking for a guideline.  You are looking for a "cookbook" approach to fermentation.    You want someone to write pitch N number of cells into V volume of wort, hold at T temperature, and it will work every time. 

[evil_morty]

considering how many things end up not being detectable via triangle test I have to wonder if a general guideline could work out in most cases but really I have no way to tell.  just a suspicion.

You are not looking for a guideline.  You are looking for a "cookbook" approach to fermentation.    You want someone to write pitch N number of cells into V volume of wort, hold at T temperature, and it will work every time.

Tell me more!

[hopfenundmalz]

considering how many things end up not being detectable via triangle test I have to wonder if a general guideline could work out in most cases but really I have no way to tell.  just a suspicion.

You are not looking for a guideline.  You are looking for a "cookbook" approach to fermentation.    You want someone to write pitch N number of cells into V volume of wort, hold at T temperature, and it will work every time.

Tell me more!

It might be get to know how X yeast works in your system with your procedures and adjust accordingly. Listen to your yeast, talk to your yeast. Give them a good home with all the tools to do their job and be happy. This is only a little in jest, a little.

[ultravista]

Mark (S. cerevisiae) - I typically brew batches around 1.070 - 80 with WLP001. For the most part, 001 is saved from batch to batch without washing. My method being a dose of spring water, swirl like mad, and fill-up with trub-and-all, two Star-San sanitized 1/2 gallon mason jars. A few days before brew day, I take a large slurry, perhaps a cup, and start it up again with a 3 liter stirred starter.

I brew 4-5 batches a year, and this process has thus far worked well. The yeast is by all means, not fresh, but the stirred starter generally produces a nice visible layer of new creamy yeast. I have no means of measuring yeast viability or growth of the starter batch; however, every batch following this methodology has worked out well and produced the beer I enjoy consuming.

I will to try your process for an upcoming batch and would appreciate your advice in approximating the correct amount of yeast slurry and starter size for a 1.070 - 80 batch. Considering the slurry is 4 months old or older, and saved from batch to batch, where should I start? Approximately how much slurry and what starter size?

Also, my next batch will be a Heady Topper recipe with a new package of Vermont IPA Yeast (GY054). Using your process, what size shaken starter do you suggest?

[RPIScotty]

Considering the slurry is 4 months old or older, and saved from batch to batch, where should I start? Approximately how much slurry and what starter size?

Also, my next batch will be a Heady Topper recipe with a new package of Vermont IPA Yeast (GY054). Using your process, what size shaken starter do you suggest?

Everything you need to answer your own questions is either here in this thread or here:

The way you use your yeast -
https://www.homebrewersassociation.org/forum/index.php?topic=24439.msg311815#msg311815

Building a Large Starter - https://www.homebrewersassociation.org/forum/index.php?topic=24416.0

Shaken Not Stirred Lager Starter - https://www.homebrewersassociation.org/forum/index.php?topic=24460.0

Repitching Yeast - https://www.homebrewersassociation.org/forum/index.php?topic=24539.0

You can probably use the methods of estimating viability in most calculators (if for nothing else) to give you a ballpark of viability for your slurry.

[Whiskers]

I understand that cutting down overall replication time is a good thing as it reduces the time need for the yeast to "own the wort."  I also understand that this shaken-not-stirred technique is less likely to damage cells.  However, because the total number of cells being pitched is less, owing to the smaller starter volume, isn't the overall number of replications greater in the final beer wort?  Don't the number of replications influence the ester/phenol/fusel character of the beer? 

Is the idea here that the number of healthy, non-shear-stressed, cells are roughly equal when comparing a larger, fermented out starter to a small, non-stirred, shaken one?  If the quiescent cells in the fermented out starter just need more time to wake up, contamination is not an issue, and plenty of nutrients and O2 are available in the final wort, how would the final beer fermentations happen differently?  Ignoring contamination and time-to-own-the-wort, how would the final fermenations differ between, say, a 1L high krausen starter and a 1L NON-stirred, but fermented out and decanted starter?  Again, assuming good O2 and nutrients in the final wort. 

Thanks, I've just had these things on my mind over the last few weeks when reading about these 'new' techniques. 

[Stevie]

So last minute brew for tomorrow and I gave Mark's recommended method a shot. Used my flask because I like the volume markers, and I'm not sure how clean my gallon jugs are. So far I'm wondering if Mark's theory that the large amount of foam helps to give extra oxygen to the yeast. If you look at the progression of photos below, my foam went from about a liter to less than 100ml in about 10 minutes. I'll reserve judgement for when the beer is done, just wanted to mention that.


11:24


11:26


11:28


11:34

[Phil_M]

I think the idea is that when there's maximum foam, there is also maximum surface area, which maximizes the oxygen entering the solution. (The walls of the bubbles.)

I'm giving this a shot today. It seems my normal procedure is a bit like this, but on a stirplate. I've only once let a starter ferment all the way out, and it stank so bad I didn't repeat it. Usually I'll make a start the night before, then leave it on a stir plate for between 8-16 hours depending on the brew day. I'm going to give the whole "shaken, not stirred" method a shot today, no stir plate.

[Stevie]

I get that the liquid to air interface created by the foam is the main thought, but my foam lasted 30minutes and was 10% of its initial volume after 10 minutes. That's where I am questioning the theory. I don't doubt the beer will be fine though.

[yso191]

It doesn't make any sense to me, the idea that the foam disappearing would indicate that there is nothing to this method.  I would expect the foam to disappear - what else could it do?  The role of the foam is to have greater surface area for oxygen to get absorbed.  Once it is absorbed into the wort the job is done - the oxygen has saturated the wort.  But maybe I'm missing what is being said above.

[Stevie]

Right, the air to surface would be useful during the period of uptake by the yeast, but that must be longer than 10-30 min

[S. cerevisiae]

Right, the air to surface would be useful during the period of uptake by the yeast, but that must be longer than 10-30 min

According to Chris White, dissolved O₂is taken up by the yeast during the first thirty minutes.  An Erlenmeyer is a miserable vessel in which to make a shaken, not stirred starter due to its geometry.

[Stevie]

Thanks Mark

Why such a bad vessel? I got about the same amount of foam as in pictures you have posted. I used a sold stopped to seal it up and gave it a good vertical shaking.

[leejoreilly]

It doesn't make any sense to me, the idea that the foam disappearing would indicate that there is nothing to this method.  I would expect the foam to disappear - what else could it do?  The role of the foam is to have greater surface area for oxygen to get absorbed.  Once it is absorbed into the wort the job is done - the oxygen has saturated the wort.  But maybe I'm missing what is being said above.

But is the oxygen in the bubbles really absorbed back into the wort, or is it just encapsulated in the foamy bubbles? Once the bubbles bursts, the O2 is just released back into the air, not into the wort. Just like using a stone, if the O2 is bubbling to the surface it is escaping, not absorbing. It would seem that any O2 absorption occurs during the shaking, not as a result of the collapsing foam.