It would take a lot to denature an amino acid
Yeah, ... like the production of reactive intermediates (reducing agents) during the cooking process.
(Or racemization from L to D, or catalysis from metal ions or reactive intermediates, or photolysis in other cases, and whatever else would make a complete list of this.)
I see where you're coming from, but if you'll re-read, I didn't say that 'heat' did it. But it would play a part. As the temps go up, things become more energetic (well, generally, there's some cavity qed that can defeat that - but not in the average kitchen rofl ) and their reaction-velocity increases for interaction with any nearby agent.
I'm not implying the arginine is decimated or anything, just that the figures quoted were likely from the most-simple state of the most-average egg. It wouldn't make sense to alter the baseline in some random way (various time under various heat in various containers and resultant agents) and present that as a scientific table of the contents of an egg, assuming someone else would cook it the same way in review.
(Actually I thought if anyone was going to jump me for that post, it'd have been for my math - which I did in my head while exhausted.)
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