Why is gluten important? Or is it?
(Pollan on cooking) “But even better, I found, is the satisfaction of temporarily breaking free of one’s accustomed role of producing the one thing – whatever it is you sell into the market – and being the passive consumer of everything else.”
This is the third article I draw from Michael Pollan’s book “Cooked”. Today we look at gluten.
Barley rarely registers in our diets today but before the invention of bread, it was a staple food in the West. Barley was one of a number of edible grasses but it grew quickly and was highly nutritious. It made porridges, beer and flat bread. Yes flat, because no amount of leavening would get the bread to rise.
Gluten is found primarily in wheat and to a lesser extent in rye. To be more precise, gluten is not found in wheat but its precursors are, namely the proteins gliadin and gluetin. When these two proteins are moistened with water and combined they form gluten.
Gliadin allows dough to be stretched and shaped and gluetin allows it to bounce back to its original form. Gluten therefore gives bread its “muscle”.
Gluten has no nutritional value. Its benefits lie elsewhere.
The rubbery properties of gluten makes it an ideal medium for trapping air which is created in the wet fermenting dough during the baking process. It forms a matrix that stretches like a balloon to contain the fermenting gases. Without the extensible and elastic gluten, bread would not rise.
So when did bread overtake barley as the main staple grass? Wheat was first cultivated nearly 10,000 years ago. The early wheat contained too much gliadin and not enough glutenin to trap the fermentation gases. The origins of bread is subject to ongoing debate among botanists but at about 3,000 BC somewhere in the Middle East a stalk of wheat appeared that contained just the right proportions of gliadin and glutenin. When this was crushed and mixed and baked we saw the first risen loaf of fluffy bread. The world did not look back.
Today no crop is more important than wheat, with rice coming second. Wheat accounts for a fifth of the calories consumed in the human diet.
Other cereals produce more calories per acre (corn and rice) and others are easier to grow (corn, barley and rye) and still other are more nutritious (quinoa) but wheat sits at the top of the totem. Why? Gluten. Humans love leavened bread.