Three-Build System - Firm Starter

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Yippee on 4 May 2009 at 14:28

What is the benefit of building a firm starter from barm before incorporating into the final dough? 

Could it be that this allows the critters in the barm to propagate into larger population, hence making the starter more powerful?

Thank you.

Toast

LindyD on 4 May 2009 at 19:42

You must be reading Peter Reinhart, as he is the only author who used the term "barm," which is defined by Wikipedia as:

Barm is the foam, or scum, formed on the top of liquor (i.e. fermented alcoholic beverages such as beer or wine, or feedstock for hard liquor or industrial ethanol distillation) when fermenting. It was used to leaven bread, or set up fermentation in a new batch of liquor. Barm, as a leaven, has also been made from ground millet combined with must out of wine-tubs [1] and is sometimes used in English baking as a synonym for a natural leaven.[2] Various cultures derived from barm, usually Saccharomyces cerevisiae, became ancestral to most forms of brewer's yeast andbaker's yeast currently on the market.

"Barmy" is also British slang for "crazy", comparing the foamy texture of barm to the perceived emptiness of such a person's head.

What you're doing essentially is building a firmer starter from your original culture.   I've found there's a subtle difference in the taste of sourdough bread which uses a firm starter, compared to my normal starter, which is about 75% hydration (my firm starter is 64%).

I admit that I flunked Reinhart's seed culture and barm chapters.  It looked extremely complex and wordy to me so I switched over to Hamelman, whose instructions for building a levain I could easily follow.

 

Essentially, I think you are allowing the starter to propagate and grow. A fair number of SD revipes seem to do this.

It's my impression that employing multiple builds is also a device for achieving a desired balance between lactic and acetic acid, as well as yeast. This is done by using different hydration levels and fermentation temperatures for different builds. 

I haven't really analyzed Reinhart's methods in these terms, but his use of 3 builds with multiple cold retardations in this San Francisco Sourdough in "Crust&Crumb" certainly results in a delicious bread.

David

 

I admire knowledgeable bakers in this community like you.  Many of you are passionate about baking, enthusiastic to lend your helping hands whenever needed.  I consider myself lucky to be here.