How Gluten-Free Bread Works
To make traditional breads, you need an astonishingly small number of ingredients: usually flour, water, yeast, and salt. That’s it. With just those four ingredients you can make baguettes, rolls, sourdoughs, loaf breads, heck- even soft pretzels!
These breads work because of a little protein called gluten which is responsible for holding everything together. Gluten, found in cereal grains like wheat, spelt, rye, etc., is actually a combination protein made of two parts wrapped up in each other: gliadins and glutenins. When gluten becomes “activated” in the presence of water and motion (as when you’re kneading dough), it acts like culinary glue, keeping the flour-based foods together and it adds to the tender, airy quality of breads and cakes.
But what about gluten-free breads? How does a gluten-free bagel hold together when there isn’t any glue?
The answer: other ingredients which accomplish the same task!
Gluten-free breads are made using all sorts of grain and legume flours which are naturally free of gluten, including rice, almond, buckwheat, chickpea, sorghum, quinoa, and millet. If you were to toss any of these flours with water, yeast, and salt, you’d end up with one lovely mess that wouldn’t go anywhere… except maybe over your kitchen counter. You need to ADD something to take gluten’s place and act as a binder to keep all those good things sticking together!
Nature has provided lots of options for us to achieve this. You’ve probably heard of these ingredients, or seen them on food labels, and they can usually be classified in two categories: gums and starches.
Gums: Common gums found in gluten-free breads include xanthan gum and/or guar gum. Xanthan gum is a powder derived from an inactive bacterium called Xanthomonas campestris. These bacteria are allowed to ferment on a sugar and the process produces a gel that is subsequently dried and milled to create the powder. Xantham gum is actually a polysaccharide, which means a sugar made of many smaller sugars. Guar gum is a powder made from ground up endosperm of guar plant seeds. About 20-40% of each seed consists of a substance called galactomannan gum, which forms a thick gel when mixed with water. The guar plant is native to India and guar is actually Hindi for “cow food”!
Starches: Common starches found in gluten-free breads include corn, tapioca, arrowroot, and/or potato. Extracting all of these starches requires a surprising amount of steps and not a small amount of equipment but they all boil down to a few basis stages: the plant components are separated to isolate or release the starch (in the case of corn, the kernel needs to be disassembled; the others simply need to have their cell walls burst apart through mashing) and the starch is then washed out, refined, purified, and finally dried. Corn starch is such a ubiquitous substance around the world and has been around for centuries. It’s made from the endosperm of corn kernels. Tapioca starch comes from the roots, or technically the tubers, of the cassava plant of South America. Potato starch is made from the whole potato tuber and the starchier the variety, the better (Russets are prime starch potatoes). Arrowroot starch comes from the tubers of the arrowroot plant which, like cassava, is sourced in South America.
Gluten-free bakers typically use combinations of both flour and starches/gums to make their products because each one behaves a bit differently. But the bottom-line is that together, they behave like gluten, and that’s how gluten-free bread works!