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A brand new yeast starter calculator

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Ale
11 gal batch
1.070 wort
100 billion overbuild
yeast production Oct 1
4 liter flask

I get a two step process, second step is 2.5 liters. But only tells me what to do with 2 of the liters... 1.831 liters into batch, 0.169 liters for the overbuild.

That's a legit bug report. Hang on, I'll address it.
 
Okay, Eric - that bug should be fixed. Running your numbers, I am now advised to pitch 2.157 liters and harvest .343.
 
New update!

Added logic on the multi starter step that saves overall starter volume.

The old method would try to get as close to possible to your needed cell count in every step, then add a step if necessary. This actually resulted in more total wort being needed.

Take a brewer with a 2.5 liter flask, trying to make five gallons of 1.060 lager with 71% viability of a single vial (100 billion cells). Brewer also wants to overbuild by 100 billion, yielding a total need of 519 billion cells.

In the old method, the calculator would make step 1 a 2.5 liter starter, yielding 424 billion cells. This is not enough, so it would step up ad make a 2 liter step, yielding 610 billion cells. Total starter wort is 4.5 liters under this method.

The second step has such poor growth due to the high inoculation rate.

Under the new logic, the calculator instead goes with a first step of 1 liter, yielding 212 billion cells. It then steps up to a 2.5 liter starter, yielding 565 billion cells. Total starter wort is 3.5 liters under this method, a full liter less!
 
I'v previously read about "yeast banking" and have been wanting to try it.

I think this calculator would be a great starting point to adapt and ease that process.
 
Just spit balling here: MAYBE you could create a service where users can catalog their yeast starters or yeast bank items, this service would track the generation number, viabilities, etc. You could just log in and select a vial from your "bank", input your new starter params, and have your calculator do the rest of the work... I'd use this service.

[edit] You could keep notes from generation to generation to track how things change. The "app" could create nice family tree visuals. It could warn you or email you when viabilities are getting too low for a particular item. I could go on and on...

[edit] There could be a social aspect to it, people could review yeast strains and discuss the flavor impacts, how it performs from generation to generation, how suited they are for certain styles, share attenuation data and other stats...
 
Very cool calculator. I'll definitely use this in the future. Any chance you can make the units selectable? I can starters in quart and half pint jars, so it would be a lot more convenient to be able to see the quantities in quarts.
 
Awesome calculator. This will now be my go-to. I really like how it does all the step ups for you.
 
Thanks for the positive feedback.

Hmmm, interesting ideas, kraken. I can honestly say those won't be immediate, but they are worth thinking about.

Selectable units is on the upcoming updates list.
 
+100

Lots of work put into your site...... Thanks for sharing! I am sure it will come in extremely handy!!!!!
 
Great calculator, I am definitely going to use it on my next brew!

It appears that the combo boxes to select the aeration method always store the last value used, so its difficult to switch between shaking and stir plate, for example, since you have to go through each step and adjust. I am wondering if you only need to choose once - would someone really use a stir plate for phase 1, but then shake for phase 2?
 
Could you put the units on the custom pitch rate as well, just for consistency. :)

Following up with your previous example of the new stepping up auto suggestion, shouldn't you separate some of the first step starter to use to inoculate the 2nd step rather than, for lack of a better phrase, pitching onto the whole yeast cake? This would keep the inoculation rate between 25-100 rather than the suggested 174~

Example:
Wort: 5.5G batch 1.085 OG 100Bil overbuild. Cells needed 431
Yeast: 100B, 2 months old, 62% viable. 62B.
Starter: 2.5L flask, 1.037 OG, volume 1.5L, grams 151g

step 1:
1.5L, 41.3 Innoc, 212B cells, Total cells 274B, Growth factor 3.42

Step 2:
1.5L, Innoc 182.7, new cells 169B, total cells 443, growth factor 0.62.

Would it not be better to do a 1.5L starter, harvest the 100B cells from the first starter, separate the remaining first step starter in order to get a more promising inoculation rate for the 2nd starter then pitch both the exasperated 1st starter and the cold crashed 2nd starter?

1.5L 274B cells becomes
1) 100B .5L
2) 1B .6666L stored for later
and
3) .333L used to pitch onto the 2nd starter
 
Could you put the units on the custom pitch rate as well, just for consistency. :)

Following up with your previous example of the new stepping up auto suggestion, shouldn't you separate some of the first step starter to use to inoculate the 2nd step rather than, for lack of a better phrase, pitching onto the whole yeast cake? This would keep the inoculation rate between 25-100 rather than the suggested 174~

Example:
Wort: 5.5G batch 1.085 OG 100Bil overbuild. Cells needed 431
Yeast: 100B, 2 months old, 62% viable. 62B.
Starter: 2.5L flask, 1.037 OG, volume 1.5L, grams 151g

step 1:
1.5L, 41.3 Innoc, 212B cells, Total cells 274B, Growth factor 3.42

Step 2:
1.5L, Innoc 182.7, new cells 169B, total cells 443, growth factor 0.62.

Would it not be better to do a 1.5L starter, harvest the 100B cells from the first starter, separate the remaining first step starter in order to get a more promising inoculation rate for the 2nd starter then pitch both the exasperated 1st starter and the cold crashed 2nd starter?

1.5L 274B cells becomes
1) 100B .5L
2) 1B .6666L stored for later
and
3) .333L used to pitch onto the 2nd starter

Very interesting idea. I will tinker with it.
 
HBD, a very nice yeast calculator indeed! I like that you've recreated the wheel in your own perspective, and that the calculations don't exactly match up with any other calculators out there (though they are very close). These are all good things in my eyes. The auto-stepping feature is nifty also. And the viability assumption you've made (i.e. halving of current viable yeast to never reach zero) is probably more in line with actual yeast that arriving at zero viability within a year - intuitively and from experience, it makes more sense.

A couple ideas for change:

-When playing with previous "steps" in the starter, the future "steps" are defaulted to a predetermined volume. It makes it hard to see how adjusting a previous step affects a future step without having manually reset the future step to what it was prior to being defaulted. Trying to play with different values in previous steps becomes annoying, to say the least.

-I don't "mesh" well with the layout of this calculator. It feel very disjointed and spread out, and doesn't feel like a "tool" but more like a data entry screen, or checkout screen when I'm buying something online. I would like to see the calculator "tool" encased in some way that makes your eyes say: "Here's the tool and all of the tool; everything else is information".

Regardless of my ideas of change, your calculator is very well thought out and adds a new perspective on yeast starter calculation. Thanks for sharing!!
 
HBD, a very nice yeast calculator indeed! I like that you've recreated the wheel in your own perspective, and that the calculations don't exactly match up with any other calculators out there (though they are very close). These are all good things in my eyes. The auto-stepping feature is nifty also. And the viability assumption you've made (i.e. halving of current viable yeast to never reach zero) is probably more in line with actual yeast that arriving at zero viability within a year - intuitively and from experience, it makes more sense.

A couple ideas for change:

-When playing with previous "steps" in the starter, the future "steps" are defaulted to a predetermined volume. It makes it hard to see how adjusting a previous step affects a future step without having manually reset the future step to what it was prior to being defaulted. Trying to play with different values in previous steps becomes annoying, to say the least.

-I don't "mesh" well with the layout of this calculator. It feel very disjointed and spread out, and doesn't feel like a "tool" but more like a data entry screen, or checkout screen when I'm buying something online. I would like to see the calculator "tool" encased in some way that makes your eyes say: "Here's the tool and all of the tool; everything else is information".

Regardless of my ideas of change, your calculator is very well thought out and adds a new perspective on yeast starter calculation. Thanks for sharing!!

Thanks for the kind words. I appreciate your input. It's hard to make the thing auto calculate steps, but not do it if you tinker. And honestly, a lot of times, you still *do* want it to auto calculate subsequent steps after you change a given step.

I may look at adding a setting to prevent it from auto calculating if the user prefers. Right now, I'm working on accommodating other units of measure (liters/imperial gallons for batch size, quarts for starter flask/ step size, ounces for DME).

I will also see what I can do about the interface. It's tough, ass there is just a LOT of data to be manipulated... and I suck at design. We'll see how I can improve it.
 
Thanks for the kind words. I appreciate your input. It's hard to make the thing auto calculate steps, but not do it if you tinker. And honestly, a lot of times, you still *do* want it to auto calculate subsequent steps after you change a given step.

I may look at adding a setting to prevent it from auto calculating if the user prefers. Right now, I'm working on accommodating other units of measure (liters/imperial gallons for batch size, quarts for starter flask/ step size, ounces for DME).

I will also see what I can do about the interface. It's tough, ass there is just a LOT of data to be manipulated... and I suck at design. We'll see how I can improve it.

At the very least a couple borders would be handy to "encase" the calculator.

Maybe instead of it auto generate, or perhaps in addition to, provide a button that will calculate new auto steps, if you changed a previous step. Sort of an update to the subsequent steps.
 
HBD, Here's a hack at some layout changes that please MY eye; granted, I'm only one person. Obviously it would need some polish but kind of gives an idea of what I'm thinking when I talk about the layout. Snag the source if you want; just let me know when you're done because I want to take it down after you've looked it over.

http://justfortesting.byethost12.com/HBDYestCalc/yeast_calculator.html
 
@ homebrewdad

Thank you for designing and sharing this calculator. I tried it for the first time today and have found it very user friendly - especially as I needed a 2 step starter and it automatically calculated it for me.

It is saved to my favorites and it will be the calculator I use from now on.
 
Very nice, homebrew dad, I just made a starter that I overbuilt then harvested a batch of clean yeast for my next brew and pitched the starter in 5 gallons of Citra IPA. It's bubbling away and now I get to make a the next batch of yeast for free!!! Ya just can't beat that.
Thanks again for your hard work!!!
 
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