August 16, 2011 - 10:40am
Conversions
Hi!!
I was wondering if anyone had a good way to do a starter conversion for a bread recipe that uses dry instant yeast ..in other words how much starter to replace dry yeast. I have a great recipe that I have been using and would love to try to use my new starter with it. Thanks!!
The short answer is that there isn't any one-to-one conversion formula. You are, in essense, converting the bread from one that is commercially yeasted to one that is a sourdough- or levain-based bread. The two will taste differently, proof differently, etc.
That said, most levain-based breads are based on starters in which the prefermented flour is between 15% - 25% of total flour weight. This means that you must recalculate your entire dough formula to account for the flour and water in your starter, as well as decide if you will be using a relatively liquid starter (say 100% -125% hydration) or a firm one (say 60% hydration).
The best explanation - and guide - for what you want to do can be found in this excellent piece by Susan from her blog "Wild Yeast."
Good luck,
Larry
A cup of ripe starter can be used in place of a pack(.25 oz or 2 1/2 tsp ±) dry yeast.
http://www.sourdoughhome.com/usingastarter.html
That's a good starting point.