I rely on my audience of scientists and/or science buffs to keep me honest in all things technical (I was a Philosphy major, for pete’s sake). Regular reader Hans chimes in with this about steam and bread crust:
When was the last time you stuck your face in a plume of steam to feel
the cooling effects? Steam condensation is a process that releases A LOT of heat (because of the latent heat of water if you want to get technical). That’s why steam burns are so bad. If that seems counterintuitive, just remember it’s the opposite of why causing ice to melt (by adding salt) makes things colder, and why we do that when making ice cream.
This high heat transfer is part of what makes steam so great, along with the other things you mentioned.
Well alrighty then! I have to say this makes sense, given that under-proofed bread rarely browns no matter how much steam you apply to it. That to me says that the bulk of the enzymatic starch-sugar conversion happens before the bread is ever put into the oven.
I’ll have to look into this, since the idea that water evaporation helps keep enzymes working is well-established dogma in a many baking circles — some of the world’s preeminent bread bakers talk about it. But then if I had a dime for every technical error I’ve seen repeated in text books and on cooking shows…
Thanks Hans! I’ll get back with you as soon as I’ve delved into this a bit more!