I love bread. I haven't met a kind of bread that I did not like. In fact, I am pretty certain that bread and I are soul mates, designed for one another is a kismet fashion. I could go on and on about all the kinds of breads that are out there from flat breads to Irish soda breads, the world of breads will never cease to amaze me. But that's not what I am here to talk about. I am here to talk about chemistry.
The basis to any bread is flour. In the baking world, there are multiple types of flour including: whole wheat flour, rye flour, peanut flour, cake flour, all-purpose flour, bread flour, etc. The list can problem travel down one arm and up the other. Flour is serious business. Certain flours are exchangeable because they are similar in chemical properties. Others would be absolute destruction if used in exchange for another type of flour.
Bread flour is high in gluten content. Now you are probably staring blankly at the screen wondering why you even decided to read this blog. Trust me, I questioned my sanity, the universe, and all of my morals and principles when I encountered that little factoid too. But it's simple, or at least it will be once I am through explaining. Gluten is the fabulous little doodad that gives the bread its texture and helps support the bread when it is rising. It basically just helps things stick together.
Look at a piece of bread. Like, hold it up to your nose. Now do you see those little holes? Those were created by the release of CO2 from yeast (my best friend and a matter to be discussed soon). But, the reason that the bread does not just crumble and fall apart because of all the air bubble escape pods is because of the gluten. The gluten traps most of the gases that are released during the rising phase.
The Chinese deemed gluten as the "muscle of flour" because it is essentially what gives bread it's strength. Gluten is made up of proteins. Flash back to high school biology, what is a protein? If you were not scared off by my mentioning of high school, then you are still reading this and have already googled "what is a protein?". Job well done. A protein is basically a long string of amino acids. Gluten proteins are around one thousand amino acids long. All of the sudden the whole "muscle of flour" nickname makes sense.
When the gluten is dry it does not move or transform, once in contact with water the gluten molecules are able to move, form, and break bonds with each other. In other words, it gets sticky and mushy. Like play-doh.
Let's recap. Firstly, any serious baker knows that there are several types of flour, each serving a unique purpose. Why? Because they have different chemical compositions. Bread flour is high in gluten, which means that it is an excellent choice if you want to use it with yeast since it is such a powerful force in entrapping the gases. Trapping the gases= making the bread rise. That is the reason behind the whoosh of air that escapes whenever you "punch down" bread that has been rising.
Not all baked goods want to work with flours that are high in gluten content. For instance, cakes and pastries pretty much detest gluten. Like seriously, they just do not get along. But we'll get more into that when the time comes.
Shortening-whether it's butter, margarine, or lard-interferes with the way gluten-forming proteins in flour interact with water. This makes for short strands of gluten, which is the key to flaky pastries and crusts.
Whole wheat flour contains about 14% protein, while pastry flour might contain half as much. You can find out how much protein is in a flour by looking at the nutritional information on the package!
Gluten is both plastic-able to change shape-and elastic-able to spring back into place.
Gluten is not only used in baking. It's also great for "beefing up" vegetarian cooking.
Recipes for cornbread and pancakes often warn you not to mix the batter too much. For these breads, overmixing can make the gluten too strong, which makes for a tough, chewy finished product.
When the gluten is dry it does not move or transform, once in contact with water the gluten molecules are able to move, form, and break bonds with each other. In other words, it gets sticky and mushy. Like play-doh.
Let's recap. Firstly, any serious baker knows that there are several types of flour, each serving a unique purpose. Why? Because they have different chemical compositions. Bread flour is high in gluten, which means that it is an excellent choice if you want to use it with yeast since it is such a powerful force in entrapping the gases. Trapping the gases= making the bread rise. That is the reason behind the whoosh of air that escapes whenever you "punch down" bread that has been rising.
Not all baked goods want to work with flours that are high in gluten content. For instance, cakes and pastries pretty much detest gluten. Like seriously, they just do not get along. But we'll get more into that when the time comes.
Did you know?
Shortening-whether it's butter, margarine, or lard-interferes with the way gluten-forming proteins in flour interact with water. This makes for short strands of gluten, which is the key to flaky pastries and crusts.
Whole wheat flour contains about 14% protein, while pastry flour might contain half as much. You can find out how much protein is in a flour by looking at the nutritional information on the package!
Gluten is both plastic-able to change shape-and elastic-able to spring back into place.
Gluten is not only used in baking. It's also great for "beefing up" vegetarian cooking.
Recipes for cornbread and pancakes often warn you not to mix the batter too much. For these breads, overmixing can make the gluten too strong, which makes for a tough, chewy finished product.
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* Source: McGee, Harold. On Food and Cooking: The Science and Lore of the Kitchen. New York: Scribner, 2004.
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