Gluten (from Latin gluten, "glue") is a protein composite found in wheat and related grains, including barley and rye. Gluten gives elasticity to dough, helping it rise and keep its shape and often gives the final product a chewy texture. Gluten is used in cosmetics, hair products, and other dermatological preparations.
Gluten is the composite of a gliadin and a glutenin, which is conjoined with starch in the endosperm of various grass-related grains. The prolamin and glutelin from wheat (gliadin, which is alcohol-soluble, and glutenin, which is only soluble in dilute acids or alkalis) constitute about 80% of the protein contained in wheat fruit. Being insoluble in water, they can be purified by washing away the associated starch. Worldwide, gluten is a source of protein, both in foods prepared directly from sources containing it, and as an additive to foods otherwise low in protein. Get The best quality Isolated Whey.
The fruit of most flowering plants have endosperms with stored protein to nourish embryonic plants during germination. True gluten, with gliadin and glutenin, is limited to certain members of the grass family. The stored proteins of maize and rice are sometimes called glutens, but their proteins differ from true gluten.
Unless you have celiac or an allergy, gluten might be largely beside the point. According to the researchers, most of us can tolerate gluten.
It's all about quality
Keep in mind gluten is the protein portion of the grain, proteins have differing levels of quality. For example a sprouted wheat berry is going to have a higher quality based gluten than a traditional wheat gluten. And, you will see potato starch used as an adjunct order replacement for gluten. But potato starch in Itself is a poor quality replacement as it is high glycemic and high load.
I would place the emphasis on the quality of the protein rather than focusing on being gluten-free and eating poor quality low fiber high glycemic load replacements like potato flour or potato starch.