Betcha can't un-fry an egg
Yeah, some proteins don't denature reversibly, eggs are a good example. And to your point tom, the brewing literature might have the information, you're right. But they might not have done the required experiments either, I really don't know. Clearly the proteins are inactivated at higher temps, and just as clearly they are irreversibly denatured at some
point before the fermentation or mash temp profiles would have little meaning. But where is that point where they are irreversibly denatured? Is it just in the boil, or is it some point before that, and if before that, when? Like Kai said, there is a time/temp component, but I haven't seen any data from the right kind of experiment to determine the answer.
Anyway, I'll do some digging and see what I can find.