Since I talk alot about being gluten free and specifically about gluten free brewing, I thought it might be good to go back to the start and talk a little bit about what gluten is and why it's bad for those of us that react. As a disclaimer, I'm not a bio-chemist, gastroenterologists, dietician or, hell, even a scientist really. I'm just taking information I've gleaned over the past few years to share with you.
Gluten is a protein composite that largely comes from wheat and the wheat family (genus triticum) of grass-related grains (like barley and rye). It is called a composite because it is actually two proteins, gliadin and glutenin, that travel together in these. They are bound up with starch in the endosperm of these plants. For brewers out there, the starch is what we're after when we're trying to make beer and for clear beers, like lagers, the proteins left over are an anathema. There is something to be said, however, for those proteins when we're making something that requires more mouthfeel, but that's a topic for another day. The Gluten composite is what makes bread stretchy and is a primary source of protein the world over (although admittedly, not an essential amino). It is added to a myriad of products as a thickener and as a texture agent and even in some cosmetics. This is a seriously popular protein largely because it is cheap, and because it's not water soluble, it can be easily obtained by washing the starch out of wheat.
Our body uses a toolbox full of specialized enzymes to break down the proteins into the amino acids and then those acids into the building blocks our body needs to build and repair cells. Gliadin is a strange duck because the enzymes in our toolbox can only break down its constituent long chain aminos into peptides or short chain amino acids, rather than into more digestible molecules. The end result of this is that in order to absorb these peptides, our small intestinal walls will separate in order to let them through. When a peptide enters the body in that way, our immune system sees them as an enemy and attacks. In a normal person, those gates will either not open or close immediately when our immune system kicks in, and the remaining peptides will be flushed. In those sensitive to gluten, the walls stay open the leaky intestine and our immune system begins reeking havoc on our body.
At this point there is no known enzyme that can do more than break gliadin into peptides so there is no magic pill. Those whose system opens the gates to the peptides will stay that way until there are no more of those peptides in the system. So really, the only option is to remove them from the diet entirely. For those of us that like beer, the question is, what do the particular characteristic of gluten bring to beer and how can we simulate those using a substance that is fully digestible. That is the topic for another day.