Gluten.
Flour and water, stirred, make a paste. Kneaded, the same paste becomes a dough that stretches and springs back — gluten has formed.
Wheat flour contains about 8–14 % protein, most of it two kinds that do nothing on their own: glutenin, long chains that link end to end, and gliadin, smaller and coiled. Add water and they hydrate; work the mixture and they line up and bond into gluten, a network that is both elastic (glutenin, springing back) and extensible (gliadin, flowing). That network holds the bubbles of a rising bread, gives noodles their bite and makes pastry tough if overworked.
Three things build gluten: protein in the flour, enough water, and time or work — kneading, or simply resting so the proteins link on their own (autolyse and no-knead bread, XXIV.4). Two things hold it back: fat, which coats the proteins, and sugar, which competes for water. The workshop builds a dough.
Below: gluten development against kneading time for bread, all-purpose and cake flour, and your dough with the water, rest and fat you choose (a teaching index, 1 = well developed).
- Name the gluten proteins.
- Explain what builds and what limits gluten.
- Choose flour and method for chewy or tender results.
- Use rest instead of work.
Water, work and time
A 12 % protein flour at 65 % water, kneaded eight minutes, reaches a development of 0.63 on this index. Leave out the kneading but add more water and twelve hours of rest — the no-knead method — and it reaches 1.00: given time and water, the proteins link by themselves. Add 30 % fat and the same kneading gives only 0.19, which is why brioche needs long mixing and why shortbread, with lots of butter, low-protein flour and little water (0.06), stays crumbly.
Choose accordingly. Bread and chewy noodles want high-protein flour, enough water and work; cakes and tender pastry want low-protein flour, little mixing and fat to shorten the strands (IX.9, XXV.4). Chinese flours are graded the same way — 高筋 for bread and pulled noodles, 中筋 for dumplings and steamed buns, 低筋 for cakes. Salt tightens gluten a little; acid and enzymes in some ingredients loosen it.
Mix 100 g of flour with 60 g of water into a shaggy dough and leave it covered for 30 minutes. Then pull a small piece: it already stretches a little. Knead the rest for five minutes and pull again; it stretches thin enough to see light through — the "windowpane" of developed gluten.
Terms
- Glutenin
- Long wheat proteins that link into elastic chains.
- Gliadin
- Smaller wheat proteins that make dough extensible.
- Gluten
- The network glutenin and gliadin form with water and work.
- Autolyse
- Resting flour and water before kneading, letting gluten develop on its own.
Sources
- A teaching value chosen for the course: the right order of magnitude and shape, not a measurement of a particular food.
- H. McGee, On Food and Cooking: The Science and Lore of the Kitchen, 2nd ed., Scribner, 2004.