Have you, like catmanager, been wondering why Menu Foods is importing wheat gluten when wheat is grown all across Canada and the United States? More generally, why does the United States import 70 percent of all the wheat gluten it consumes? Even more generally, what is wheat gluten?

Catmanager confesses he had a misperception about wheat gluten. I thought it was simply a part of the wheat. Seems I forgot my high school biology: the wheat seed, or kernel, comprises the bran, the germ, and the endosperm (here’s a diagram). But I wasn’t completely off. I was just thinking macro rather than micro. Gluten is found in the cells of grains like wheat.

First, a little about cells. They contain both living and nonliving substances. The living substance is the protoplasm. The nonliving substances include carbohydrates, proteins, crystals, and fats, collectively referred to as ergastic substances. If a cell were a store, the employees would be the protoplasm and the ergastic substances would be the inventory.

Gluten is an ergastic protein. Specifically, an

amorphous mixture of proteins found combined with starch in the endosperm of some cereals, notably wheat, rye, and barley. It constitutes about 80% of the proteins contained in wheat, and is composed of the proteins gliadin and glutenin.

Wheat gluten, then, isn’t something easily separated from the rest of its wheat-ly components (you can’t simply thresh the wheat to get to it). In Western food culture, the wheat gluten is generally not removed, becuase it is needed to give breads their “chewy” quality and for leavening to occur.

The Chinese were the first to figure out how to extract wheat gluten. The process is relatively simple: form a simple water and flour dough; then rinse and knead the dough with fresh water until it is free of starch and bran. The resulting sticky lump is wheat gluten. When cooked, it becomes firm and will absorb flavors from the ingredients with which it is cooked. Wheat gluten as a stand-alone food product is widely used throughout Asia, often as a meat substitute. (If you’ve ever been to an Asian foods market and wondered about all the fake meat products in the frozen-foods section—imitation beef, turkey, chicken, squid, catfish, etc.—those are all made with wheat gluten. So, oddly, is Tofurkey.) In the West stand-alone wheat gluten is more commonly called seitan, and unless you’re a vegetarian or on a macrobiotic diet, the chances are good you haven’t eaten any or at least haven’t been aware of eating it (the stuff is included in some processed foods).

Now the import of wheat gluten to the United States makes a bit more sense. It’s just not as widely used here as in other parts of the world, so it’s more economical to import what we do need. What surprises catmanager is where we get our wheat gluten from. In 2006 the United States imported $141.5 million worth of wheat gluten, almost double the amount in 2001. Most came from Europe. Less than 1 percent came from Asia, and less than 0.01 percent came from China. Catmanager wonders what portion of that amount went to Menu Foods.

(Note: I obtained the trade data from the U.S. Department of State TradeStats Express Web site. Just before posting, I checked the site again and found it to be nonfunctional. All I see is a blank, white page or a server error.)