The Fresh Loaf

A Community of Amateur Bakers and Artisan Bread Enthusiasts.

Need Math Help: Starter Build

BXMurphy's picture
BXMurphy

Need Math Help: Starter Build

I know it's here but I can't find it after searching. Please forgive redundant question.

Recipe calls for 115g starter at 100% hydration. How much should I scoop out of my big jar of 100% hydration starter in the refrigerator to finish with 115g after a three-stage build each at 1:1:1?

I know it's about 4.5g but I did it with some trial and error with childish math working backwards.

Can someone help with a quick formula done on a non-scientific calculator?

Murph

barryvabeach's picture
barryvabeach

Murph,  I don't have a formula, but I come up with 121 grams, which means you can scoop out 115 from the 121 after the triple stage, and you should be fine.  I often plan it for a little extra, and that amount goes back into the fridge.

dmsnyder's picture
dmsnyder

If you are feeding your starter 1:1:1: (by weight is assumed), and you need to end up with 115 g of active starter, and you want to arrive there after 3 feedings:

It is probably not practical to do this without any waste, i.e., discarded starter from the intermediate builds, but here is the math if that is your intention:

Final Starter Build

117g = 39g each of starter, water and flour.

Penultimate Starter Build

39g = 13g each of starter, water and flour.

Antepenultimate Starter Build

15g = 5g each of starter, water and flour.

Happy baking

BXMurphy's picture
BXMurphy

"Math @ Murph" Ha! :)

Thanks, Dave! (That's your first name, right?)

I'm amazed that this site is 10 years old and still going strong. Praise God! I hesitated to post this question because everything has already been answered. It's so nice to see some of the Old Guard like you still contributing. Thank you for your help!

Your method is what I did to get the answer. It seemed like so much trouble. I was thinking there had to be a rule of thumb kind of thing out there for lazy guys like me. :) And then came Stan's answer below.

I'm very much digging on dabrownman's No Muss No Fuss starter. That kind of lazy with his kind of results is very appealing - if you catch my drift.

I can't imagine sweating a loaf of good bread and I think sourdough is just the ticket. Thank you for all you do for the community.

Murph

BXMurphy's picture
BXMurphy

Did you just say, "antepenultimate?" Please tell me you didn't just say antepenultimate! :) Look at the big brain on Brett (Pulp Fiction quote)!

Sorry, Dave... Pulp Fiction is one of the most quotable movies I've ever watched. I loves me some Pulp Fiction! Way to rock out some of the King's english!

Murph

Elagins's picture
Elagins

here's the formula, assuming you start with 100% each of flour, water and sponge at Stage 1:

 

 Stage 1Stage 2Stage 3
Flour100%300%900%
Water100%300%900%
Sponge100%300%900%
TOTAL300%900%2700%

At the end of Stage 3, you have a total of 2,700%, so divide your final amount (115g) by 27, which gives you 4.26 grams as the amount of flour, water and sponge you need for stage 1.

Hope this helps

Stan Ginsberg
theryebaker.com

 

BXMurphy's picture
BXMurphy

That's it, Stan! That's the magic simple math formula I've been looking for that can be applied to any final weight over any number of builds on any planet regardless of hydration.

BOOM! Stan, the MAN! Easy-peasy, lemon-squeezy!

Could something like that be applied to a build like dabrownman's where he changes final hydration?

Murph

Elagins's picture
Elagins

it might take a little bit of reverse calculation, per David Snyder's methodology, but in general it's just a matter of plugging in the appropriate percentages.

S

BXMurphy's picture
BXMurphy



Here's where dabrownman changes hydration in his No Muss, No Fuss Starter. 

BXMurphy's picture
BXMurphy

Didnt seem to work as advertised on my phone so here is dabrownman's thing....

http://www.thefreshloaf.com/node/40918/no-muss-no-fuss-starter

Elagins's picture
Elagins

is to spreadsheet dbm's tables, converting the components into percentages of flour at each stage. In other words, the amount of flour at a given stage is always 100%, so at that point, it's easy enough to divide the other quantities by the flour quantity to get the relevant percentages. From there, you can do the same thing as in my table to calculate quantities based on the total amount of sponge needed.

S

BXMurphy's picture
BXMurphy

Spreadsheets are way cool but I bet most of us would rather eat some of the bricks I bake instead of pulling out a spreadsheet.

I bet I could put together a web page calculator to do that math but who would use it when Dave's method works just as well? Is scaling starters or levains a common problem without easy answers? If so, there's gotta be an app for that already, right?

Might be a fun project for this long weekend in the U.S... Google has a thing where someone could put a spreadsheet up, too.

Who knows? Let's bake!

Murph

drogon's picture
drogon

if by 1:1:1 you mean 1 part starter, 1 part flour and 1 part water (by weight), then you divide each stage by 3, so the first calculation is 115 / 3 = 39g. The 2nd calculation is 39 / 3 = 13.

So 13g starter + 13g flour + 13g water = 39g.

Once this is bubbly, then take that 39g and add in 39g flour and 39g water to give a total of 117g.

You can simply divide by 9 to go directly to the first step but doing it this way gives you the numbers for each step.

Personally I'd do this in one stage (actually, I'd take 115g starter directly from my big jar in the fridge). I also build using double the flour to starter, so 1:2:2 I think is the notation. In this case it's divide by 5 (1+2+2, so can you see where the divide by 3 came from earlier?)

So for me, 115 / 5 = 23. 23g starter + 46g flour + 46g water = 115g. Wait for the bubbles, then use.

So many different ways...

-Gordon