Does baking (or other cooking at high temperatures) significantly affect the level of caffeine in chocolate?
For example, would I get more caffeine from eating chocolate cake batter than I would from eating the equivalent amount of cooked cake?
No. Caffeine is a chemical compound that stays in there, no matter what you do to the product.
If heating destroyed caffeine, then all brewed coffee or tea would be automatically decaf, and the caffeine junkies at work would all be drinking Jolt instead of coffee.
Are you perhaps thinking of aspartame, which is destroyed by high heat? Baked goods using Equal for sweetener have to be dealt with differently.
I wasn’t asking if all caffeine was destroyed by heating, but rather if cooking (especially at high temperatures–above boiling) made any noticeable change to caffeine levels in chocolate.
My own personal experience was that directly eating some cocoa powder (it was a dare…) left me with much more of a buzz than I would have expected if I had cooked it up in some brownies and eaten them. I was wondering what the explanation was for this observation. At this point I think it was simply some sort of placebo effect (an intensely bitter taste in the mouth makes you think it’s “strong” medicine) combined with the speed in which I ate the cocoa (which probably caused the caffeine level in my system to jump up more quickly than if I was chewing my way through a plate of brownies).
Taking a pill of caffiene, or any drug, on an empty stomach will deliver the drug faster and in higher quantity than when it is mixed in with some other bulk material. It’s just a dilution effect.
Caffeine sublimates (evaporates directly from the solid phase) at 178ºC (352ºF). Theoretically, this means that baking temperatures could drive off caffeine. Whether this is a significant effect in baking brownies is less important than certain facts: the buzz from chocolate is mostly from theobromine, not caffeine, and its sublimation point is over 550ºF; chewing on cocoa powder is a more effective delivery system than brownies; and, as you say, there’s a placebo effect.
Maybe you ate more plain cocoa powder than what’s proportionally in one brownie?