[Frankenbrew]

Even though we've read it all before, it's nice to have it without all the extraneous questions and comments, even though those discussions may have helped you sharpen some of your ideas. Nice job!

[S. cerevisiae]

I think I grasp it now, maybe. My take away is that cell count calculating is more important when you are pitching quiescent yeast (slury).  Not as important if you are pitching a "close enough" amount of yeast actively in the exponential phase (high krausen).

In either case, most home brewers are usually working with an approximation at best because they do not have the ability to count.  I going to introduce an alternate method of looking at pitching rates in future entry.  The method is not a new way of looking at the problem.  It is just a way of pitching that has gotten lost in the noise  due to the overuse of/over-reliance on brewing software.

Which, if my understanding is correct, makes me wonder... when a yeast calculator tells me that 300b cells (slury) is enough, why wouldnt 200b in exponential phase also be good enough? Actually better. If it only took 3 hrs to get that 300b slury into the beginning of exponential phase, by that time my 200b high krausen cells have already become 800b. But doesnt it actually take more like 9 hours? By 9 hours mine have maxed out you would think.

Or am I still lost?

No, you are not lost.  Pitching 200 billion cells at high krausen instead of pitching 300 billion cells at quiescence gives the 200 billion cell culture an advantage over the 300 billion cell culture because it should spend less time in the the lag phase.  Even if the both cultures were pitched as quiescent cultures, the difference between pitching 200 and 300 billion cells is in the noise when dealing with normal gravity wort.  Now, high gravity wort is a different story due to increased osmotic pressure, ethanol stress, and the fact that O₂ saturation goes down as gravity goes up.  However, even in that case, an increase of less than a factor of two is not going to make a noticeable difference in outcome.

[klickitat jim]

I think I grasp it now, maybe. My take away is that cell count calculating is more important when you are pitching quiescent yeast (slury).  Not as important if you are pitching a "close enough" amount of yeast actively in the exponential phase (high krausen).

In either case, most home brewers are usually working with an approximation at best because they do not have the ability to count.  I going to introduce an alternate method of looking at pitching rates in future entry.  The method is not a new way of looking at the problem.  It is just a way of pitching that has gotten lost in the noise  due to the overuse of/over-reliance on brewing software.

Which, if my understanding is correct, makes me wonder... when a yeast calculator tells me that 300b cells (slury) is enough, why wouldnt 200b in exponential phase also be good enough? Actually better. If it only took 3 hrs to get that 300b slury into the beginning of exponential phase, by that time my 200b high krausen cells have already become 800b. But doesnt it actually take more like 9 hours? By 9 hours mine have maxed out you would think.

Or am I still lost?

No, you are not lost.  Pitching 200 billion cells at high krausen instead of pitching 300 billion cells at quiescence gives the 200 billion cell culture an advantage over the 300 billion cell culture because it should spend less time in the the lag phase.  Even if the both cultures were pitched as quiescent cultures, the difference between pitching 200 and 300 billion cells is in the noise when dealing with normal gravity wort.  Now, high gravity wort is a different story due to increased osmotic pressure, ethanol stress, and the fact that O₂ saturation goes down as gravity goes up.  However, even in that case, an increase of less than a factor of two is not going to make a noticeable difference in outcome.

Cool! I think I now know all I need to know for my purposes. Thanks

[toby]

Awesome article.  If you had a chance to team up with someone to make how-to videos on homebrew-scale yeast culturing for us visual learners, those would be worth paying for.

[HoosierBrew]

Great info, Mark. Gotta say, I've 'shaked not stirred' for a few batches and I'm sold. Not a big departure from Charlie P's old starter method, which I used for years (quart starter in a gallon wine jug), except for the shaking into foam like it owes you $. So far, 8 hours to HK seems to be the target time for most strains. Really liking it.

[ultravista]

I want to try the shaken method but only have a 1 gallon glass jug and 5L Erlenmeyer flask. The next batch in the pipeline is 1.071 - a 2L starter is appropriate.

The 1 gallon jug is too small and the flask is not the best option.

Given the situation, should I go jug or flask? Which is the lesser of two evils, smaller volume or shape of the container?

[S. cerevisiae]

I truly appreciate the compliment, Toby.  Believe it or not, writing is a subject that did not come to me easily.  I really had to work at becoming an effective writer.  I still struggle with my writing.

As strange as it may seem, I am not one for cameras or being thrust into the limelight.  Balancing a way to share what I have learned over the years with my need for privacy was at the forefront when making my decision to start sharing information on a large scale.  I see the kind of attention that Drew, Denny, Martin B, Jamil, Gordon, Charlie P, John Palmer, and the other highly visible members of the community draw at NHC, and it makes me very uncomfortable because I am introverted to point where just being in large crowds wears me out.   Being easily recognizable would make me not want to attend NHC.

[S. cerevisiae]

Given the situation, should I go jug or flask? Which is the lesser of two evils, smaller volume or shape of the container?

Neither container is optimal for a 2L starter.  Is acquiring a second jug a possibility?  If so, you can split the culture between two jugs after re-suspending the yeast in the preform.  Optimally, a 10L media bottle is probably the best option for 2L starters, but even used 10L media bottles are ridiculously expensive.   I paid $70.00 for my NOS Corning 1395 5L media bottle.   

[Tim Thomssen]

Thanks for a most excellent write up Mark!  I'm impressed that you could efficiently explain a complex subject in a way that a simple minded guy like me was able to understand.

Cheers!

[reverseapachemaster]

As strange as it may seem, I am not one for cameras or being thrust into the limelight.  Balancing a way to share what I have learned over the years with my need for privacy was at the forefront when making my decision to start sharing information on a large scale.  I see the kind of attention that Drew, Denny, Martin B, Jamil, Gordon, Charlie P, John Palmer, and the other highly visible members of the community draw at NHC, and it makes me very uncomfortable because I am introverted to point where just being in large crowds wears me out.   Being easily recognizable would make me not want to attend NHC.

You could wear a mask. Maybe a top hat to keep it classy.

[S. cerevisiae]

Great info, Mark. Gotta say, I've 'shaked not stirred' for a few batches and I'm sold. Not a big departure from Charlie P's old starter method, which I used for years (quart starter in a gallon wine jug), except for the shaking into foam like it owes you $. So far, 8 hours to HK seems to be the target time for most strains. Really liking it.

As I have mentioned many times, the method is just a take on an existing method.  I will be bringing back methods and metrics that were used in the past that have fallen to the wayside since the universal acceptance of brewing software and the incorporation of technology into brewing.  While many of the older techniques/metrics left a lot to be desired, many are more practical in a home brewery than what home brewers are using today. 

[ynotbrusum]

I used a 2 liter starter in a 3 gallon Better Bottle last night and hit it with O2 from a wand and O2 cylinder instead of shaking it (since it had no threaded top, I didn't know of a good way to be sure I could shake it sufficiently).  I awoke to krausen.  And it fell out pretty quickly as I brewed the batch.  I am looking forward to good results on this one.

[brewinhard]

Nice write-up Mark.  Thanks for taking time to do so.  I appreciated the formula examples as well.  I knew bacteria could reproduce quickly, but their exponential growth is SCARY!!

[ultravista]

Given the situation, should I go jug or flask? Which is the lesser of two evils, smaller volume or shape of the container?

Neither container is optimal for a 2L starter.  Is acquiring a second jug a possibility?  If so, you can split the culture between two jugs after re-suspending the yeast in the preform.  Optimally, a 10L media bottle is probably the best option for 2L starters, but even used 10L media bottles are ridiculously expensive.   I paid $70.00 for my NOS Corning 1395 5L media bottle.

Dang it Mark. I have 5 1 gallon jugs and did not consider splitting the starter into two. I wonder where I left my brain ...

[brewinhard]

Probably too much beer clouding your decision making.