The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Calculator to determine amount of mother starter to use?

BKSinAZ's picture

Calculator to determine amount of mother starter to use?

I make a lot of sandwich bread for the kids, but most of the recipes on the internet only show fleischmann's  jar active yeast. I would like to convert those recipes so I can use my mother starter instead of the fleischmann's jar yeast. Is there some kind of calculator that can assist? My mother starter is a 1 to 1 ratio.

LP14's picture

It would be easier to look for sourdough sandwich bread recipes since you'll need to alter your method along with the type of leavening you're using. These will also take into account the different qualities that sourdough will contribute to the loaf. There are lots of those recipe on this site and online. 

Here's one: 

In terms of converting, here is some guidance using ratios of starter to flour in the recipe:   More can be found by searching this site if you haven't already done so.

dabrownman's picture

Here in AZ in the summer we may want to use 5% and in the winter 15% t get the timing right for the bulk ferment and final proof and if you are doing a retarded proof

But once you decide what amount of prermented flour to use you can then quickly decide how to build the levain.  Use Lucy's rule of 7.  If you have 100 g of flour in the bread ans want to use 12% prefermentd flour in the winter than 100 x .12 = 120 g of prefermented flour divide the 120 by 7 and you get 17 g of starter using the closest whole number,  to use with the 100 g of flour and 100 g of water to make a 12 hour levain that totals 217 g.

If you keep your starter on the counter and it is ready to go then you just use 217 g of it.

If you are building a 3 stage levain of 4 hours each the rule of 7 works great.  17 g of starter, water and flour for the first build.  Then 2 times 17 = 34 g of water and flour for the 2nd build and the 3rd build is 3 times 17 or 51 g each of flour and water.

All you have to do is decide how much prefermented flour you want to use of the total amount of flour and that depends on what time of year it is temperature wise, how much time you have to get the bread done and what the actual process you are using for bulk and proof.