Gluten deteriorates in high temps???
So. I had heard rumors of the “fact” that gluten can be modified so greatly when exposed to high temperatures that it renders it harmless to those with celiac disease. I was highly skeptical. Still, I didn’t really know for certain one way or another.
Then, a guy on my local celiac Yahoo group, Chef David Hall, did the research for me. Well, for himself, and then shared it with the group. I asked him, and he gave me permission to print the response of the chemist he consulted to find out the scoop. I found it very interesting. (All the more so, as it confirmed my suspicions. 😉 )
I found and contacted a Chief Scientist at API Purifications LLC, in the Greater St. Louis Area, and posed the question to him with the cursory temperature range given to me by someone at the meeting, which was about 600 F to 1200 F. Below is his reply. I am withholding his contact information, as I do not have permission to distribute it.
“First of all, nothing I write here should be construed as medical advice. I am not a medical expert. If you require medical advice, you’ll need to contact a physician.
I can provide a chemically sound response to your inquiry, and that is what I will attempt here.
The information you have received from other sources appears to be sound. If you wish to chemically change gluten to such an extent that it no longer behaves as gluten in biological systems, you will have to do more than heat the molecule to temperatures usually used in cooking. What you need is severe oxidation or pyrolysis (heat-induced destruction of the molecule). However, such severe conditions are likely to cause the formation of carcinogenic compounds in whatever material you are cooking, and that of course would be a severe health problem. Therefore, from this chemist’s point of view, in any case, chemical or thermal destruction of gluten is not feasible, and should not be attempted.
It is possible that in the cooking process you will denature the protein. However, denaturing the protein is not sufficient, because to say the protein is denatured is simply to say that the tertiary structure of the protein has changed. The primary structure–the “chemical formula” if you will–has not changed in the process. What you need to do is to chemically or thermally destroy the primary structure. What that means in essence is that you must chemically change the molecule. Usually this would be accomplished through oxidation or pyrolysis. If for some reason you were interested in doing this, you would want to heat the material to at least 350 C (650 F) for 30 minutes, and you would need to have some way of proving that every part of the material (and especially any interior parts) had been exposed to that temperature for the entire length of time. Also, you would need to ensure that air flow around the material was unimpeded. But all of this is quite an academic exercise, since as I said above, you would never wish to serve anything like this to another person, or even to an animal.
My advice would be to use gluten-free products. There are many such products available, and all manner of food can be prepared gluten-free. There are many good gluten-free cookbooks, and as you are a chef, you will have a much better idea than I of where to find these.
If you do receive medical advice indicating some less severe conditions suffice to render the material suitable for gluten-sensitive patients, as a chemist I would certainly be wary of this advice. Gluten is quite a robust little protein, not an ordinary feeble protein, and it does quite well under harsh conditions. It’s a tough nut to crack, and very definitely a difficult material to degrade chemically or thermally.”
So. I think that’s a pretty definitive answer. Now, like me, you know. 😀