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Nathan Myhrvold's Recipe For a Better Oven
Tekla Perry writes: We cook our food today using technology invented to bake bricks. We can do a lot better. Nathan Myhrvold explains what's wrong with today's ovens and challenges oven designers make them better. He says, "Oven designers could do a lot to make ovens heat more evenly by taking advantage of the different ways ovens transfer heat at different cooking temperatures. At 200 C or below, convection moves most of the heat. But at 400 C, radiant energy starts doing a fair amount of the heat transfer. At 800 C, radiation overwhelms convection. Why couldn't we have an oven designed to cook primarily by convection at low temperatures that switches to radiant heating for high-temperature baking? ... The shiny skin of raw fish reflects heat, but as the skin browns, it reflects less and less energy. That’s why food under a broiler can seem to cook slowly at first and then burn in the blink of an eye. But technology offers a fix here, too. Oven designers could put optical sensors in the oven chamber to sense the reflectivity of the food, and then the oven controller could adjust the heat automatically or at least alert the cook as the surface browns. And a camera in the oven could feed to a color display on the front panel, giving the chef a clearer view of the food than a small window in the door can. Indeed, a decent optics system could allow designers to dispense with the glass in the door altogether, reducing the gap between the hottest and coolest corners of the oven and obviating the need to open the door and rotate the food midway through cooking.
The real question is "who cooks at 800C?". I do quite a bit of baking and the only reason to go over 200C is pizza.
I think repeatedly confusing C and F should immediately disqualify someone as an oven engineer. Or an oven operator, for that matter. :-)
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at 400 C, radiant energy starts doing a fair amount of the heat transfer. At 800 C, radiation overwhelms convection.
800 degrees C??? That's 1470 degrees F! Who has an oven that goes that high? That will turn just about anything into charcoal in under a minute.
Even 400 C-- 750 degrees F-- is quite a bit hotter than most ovens.
Commercial ovens, and specifically commercial salamander ovens. And what the summary failed to explain is that the heating elements get up to that temperature, not the air - hence, infrared radiation cooks the food, rather than convection through the air.
They're useful for anytime you want a quick and hard sear, including steaks, creme brulee, flash broiling fish, etc.
I modded my almost new dumb oven (2 knobs and indicator light) with cast iron plates about 5 millimeters thick on top and bottom, with some additional rails to quickly remove them if necessary. The heat up process is a bit slower, but overall the oven performs way better than stock one and bakes evenly.
This is thermal mass right over heaters for even roasting/baking.
If I want crust, I just pop on the ventilator in the oven for 10 minutes before done, perfect every time.
As for bread, i pop out the plates, Heat the oven and cast iron pot with lid to 260C, pop in the bread when hot and forget about it for 45 minutes.
If he wants Tech in the oven, well let's see his ideas. At friends house they bought new $INSERT_NAME oven (overpriced around 1500€) with all the bells all over, you can't even expect to turn it on without at least reading 10 pages of the 80 pages long manual. It's super energy saving design takes like 20 minutes to heat up to 200C or ~30 minutes to 250C. For the fun of it we popped in an NTC sensor to see what's going on in heat up and baking process. Nice SLOOOW and steady heat up, then we popped in a roast. Temperature dropped around 40C then heating back up for 16 minutes, overshoot set temperature by 18C, dropped back 21C under set temp and oscillated all the way to the end. All the micro controlling in there failed with REGULAR use.
With that price tag you expect at least steady even temperature, but noooo, $INSERT_NAME decided to screw the customer with poor excuse for an oven, and telling you that you baked your stuff wrong all your life, so they decided to set you straight.
If I wanted to die of waiting I would go to DMV line...
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