Cooking and temperature
Reactions
- Room temperature (~25C, ~70F)
- baking soda, baking powder starts reacting (though some are designed to react to more heat)
- yeast reacts decently (one-two hour rise)
- above 30C (~90F)
- melts various fats
- and e.g. tenderize
- also helps rising, if done by releasing gas or water
- above 55C (~130F)
- yeast dies, so you won't get yeast based rising anymore
- above 60C (~140F)
- various protein (e.g. eggs and gluten proteins) begin to dry out, stiffen, set
- starch granules swell with water and gelatinize (up until about 90ºC/200ºF(verify))
- above 70C (~160F)
- enzymes die, which you want in baked goods that contain enzymes (the enzymes would otherwise digest things, making for a different outcome)
- above 150C (~300F)
- Sugar caramelizes, Maillard reaction happens
- important for the golden-brown color and flavors to baked goods containing sugar
- 300-400F
- hotter releases steam faster, which can help airy things stay puffed up
Notes:
- "Preheat the overn to 350F" (175C) is common
- primarily because it's an easy convention that's decent for a lot of baking
- pastries, cookies are often baked around here
- breads:
- 200C (~390F) is a good target for a thinner, crisper crust (also affects rising?), and for leaner breads (little fat or eggs)
- 175C (~350F) may be better breads with more fat, egg, or sugar
- bread will bake above 160C (325F), but this will often make for a thicker crust (why?)
- higher, e.g. 220C (~420F) works too. Keep in mind the time may be significantly shorter than a 175C/350F.
- sourdough is hot and shorter
- filled bread may wish to cook the filling at higher temperature, then bake the bread at a more regular one
Checking bread is done
- the best check is inside temperature - basically because that indicates moisture is gone
- tapping also works, for similar reason
- also similar for the give when you poke it, the amount of drag on a knitting needle, etc.
Oven settings
Temperature
For those who do not live in the USA, the following tends to be useful:
Gas mark Celcius Farenheit Stufe 1/4 120 225 1/2 125 250 1/2 1 135 275 2 150 300 1 3 160 325 4 175 350 2 5 190 375 6 205 400 3 7 220 425 ~4 8 230 450 ~4 9 245 475 ~5 10 255 500 ~5
You should take this as approximate, because
- gas-to-temp charts usually disagree by ~5 degrees - in part due to rounding
- thermostats won't be entirely accurate
- the thermostat is often at the top. Assume that the bottom of the oven is be 10C cooler
- ...though on the forced-air setting it should be more uniform
- there are hot spots near the walls. The middle will be some amount cooler - varying by heating type as well
- Most aren't very well calibrated.
- That's as much about sensor calibration as the difference between the temperature at the sensor and at the food.
- There's some control theory details here - there is time between actuation and sensing, and a sluggish response.
- Don't be surprised is the average is higher -- the heating is throwing a kilowatt of power in there, the cooling is waiting around.
- Yes, your oven could be correcting for that, but if others don't, that just means the actual meaning of the set temperature varies between ovens to start with.
In short, don't be surprised if the variation is 10 or 20 degrees C over or under what you thought you set.
That doesn't mean you shouldn't follow your cookbook.
There are specific reasons the recipe requires a specific zone, but even processes that are specific in temperature will vary with
There are a bunch of processes that specifically need low, moderate, or high heat, yes.
There's also variation with the size of the thing.
But for most cooking, things are fine in a zone. "Preheat to 350" is really just a "preheat to moderate temperature" put in numbers
Yes, there are things that need more precision that that. The recipes will probably point that out, though.