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Ask the Inquisitive Cooks

January, 13. 2003

This week's question:
“How does fat affect gluten development?”


When making pastry crust, much effort is spent trying to make sure the gluten in the flour does not develop: Use cake flour, work the dough as little as possible, and I even heard in a class (from a French MOF [Meilleur Ouvrier de France] winner) that you add the butter at the very beginning because it coats the proteins and prevents the gluten from developing, and thus creates tender pastry crust. Now, in a standard foccacia recipe, large amounts of oil are added; in brioche, lots of butter is added...and both of these depend upon gluten development for their character. So, the question: Is there really any truth to the notion that fat added to flour actually limits or slows the development of gluten?
—Submitted by B. Bouvier

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Dear Curious Baker,

The short answer to your question is yes: Fat really does interfere with the development of gluten by coating the proteins in flour that are responsible for forming gluten. Strong doughs usually contain very little or no fat.

Sometimes, however, in doughs such as brioche, the amount of fat included is surprisingly high. In this instance, the development of gluten is affected by when the fat is added while the dough is being made.

Some brioche recipes first make a simple dough with yeast, water, and flour. Softened butter is mixed in only after the dough has been formed and kneaded to develop the gluten. Once the gluten has been formed, it remains intact, and the butter has less effect on its strength.

Other brioche recipes add softened butter directly to the flour before the dough is formed. This method, of course, coats the gluten-forming proteins, so that once liquid is added very little gluten forms. Such a delicate dough (more like a batter) results in a very moist and tender brioche. It's quite different in texture from the more breadlike brioche.

As far as focaccia goes, it too is another variation on the gluten/fat story. Focaccia is traditionally a flatbread; it doesn't rise. Any oil or fat this dough contains helps inhibit the development of gluten in the dough, so the gluten doesn't develop too much as it's kneaded. Because the gluten relaxes when the dough rests, the dough has a slightly softer texture and is easier to roll or stretch to the desired flatness. The oil in the focaccia dough performs the same function as the butter does in the brioche.


Anne Gardiner & Sue Wilson are the authors, with the Exploratorium, of the book The Inquisitive Cook.




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