"Preheat oven to 350 degrees." This may be one of the most common phrases in the cooking universe...and also one of the most misleading. If you fret over the accuracy of your oven's internal temperature reading, you're working too hard. Here's why:
In a nutshell, it's impossible to control your oven temperature, so you should stop worrying about it altogether—or so writes Slate writer Brian Palmer. While you think might 350 degrees on the dial means 350 in the oven, no residential oven maintains a 350-degree temperature for the duration of a bake session. Rather, it usually ranges between 330 and 370 degrees and, as Palmer notes, that's if it's a well-calibrated oven, which few are. What about oven thermometers, you ask? "A waste of time," writes Palmer. The variability in temperature throughout the oven chamber makes oven thermometers unreliable at best.
If that all sounds like cause for worry, it's not, and here's why: the 350-degree instruction has always been just a default recommendation:
Around the time that manufacturers put temperature dials on ovens, cookbooks had to convert their old terminology into degrees. A "moderate" oven became 350 degrees, and few writers bothered to test if 350 was really better for an individual recipe than, say 360 or 380.
Even Mark Bittman, New York Times food columnist and author of How To Cook Everything says that "oven temperatures are a convention." He prefers to think of them in four ranges: Really low (under 275 degrees); moderate (between 275 and 350); high (over 350 but under 425); and maximum. His advice: give up the numbers completely, and "get used to the visual and olfactory (and even aural) cues that food gives off while it's baking or roasting."
Sound too scary? Then get an instant-read thermometer to stick in your food while it's cooking. "Used frequently, [it] solves most issues," says Bittman.
What do you think of this advice? Does it lessen your anxiety? How comfortable are you thinking about oven temps in terms of what you need to do, i.e. warm slightly, cook through, blast, etc?
Read More: Ignore Your Oven Dial at Slate
Related: Want Awesome Pizza? Turn Up the Oven
(Image: Emma Christensen)
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I understand that this article is saying that oven temperatures are guides, so don't worry too much about the exact number since there are ranges.
However, an oven thermometer is necessary if your oven is anything like mine - it's off by 100 degrees! So if I set the dial to 375, it's actually starting to cook my food at 475, which is obviously a recipe for disaster.
Isn't this how an Aga works? It has a "simmering" oven, a "warming" oven, a "baking" oven, and a "roasting" oven. I don't think there are even any temperature dials.
And yet, when you test cookie recipes (for example) you do find there is a difference between a cookie baked at 350 and one baked at 375.
Oven temperatures does make a difference as @ALEXISRT mentioned about cookies. I've kept an oven thermometer and spot tested with an infrared thermometer and my oven DOES keep its temperature that I set. It's not a designer oven; it's a 25 year old Kennmore. I do not believe oven temperatures are a convention. If the setting on an oven is off by more than a few degrees then the oven is poorly made. Period.
@alexisrt: the article does not say that there is no difference between 350 degrees and 375 degrees. The point of the article that the temperature you choose on the dial or the screen is not always the temperature you think it is so it shouldn't surprise you when cook times vary. As a result, the temperature you pick does not matter (within reason) because you should take out the food when its done, not a set time. So if you put the cookies in at 350 or 375 and leave it in the same amount time in the same oven, yes the end result will be different. But the point is that you should take it out when ready.
I basically thought this was common sense when I read it. Isn't that how everyone cooks when you only have one oven and two or more dishes that need the oven? Say at Thanksgiving?
I think oven temperature is more important in baked goods than roasting or baking dishes like casseroles.
This is ridiculous. Get yourself a $5 oven thermometer and put your cookies in when the little needle points to 350. That's it. I even drew a little dot on my oven dial for actual 350 because it's old and off quite a bit. No need to have an anxiety attack over this.
There is absolutely no need to sit there and smell your goods to somehow assume what temperature they are baking at. What the hell Bittman??
My oven runs hot. The first time I used it was when we'd just moved in, and the pizza which should have taken 12 minutes was very nearly burnt after 4 minutes!
Fortunately, my olfactory senses caught it in time, but using an oven thermometer showed that to get the usual 180c (375f or gas mark 4) I needed to set the oven to 120c!!
Yes, once you know what the actual temp settings are, you don't need to keep worrying about it, but it's important to know - especially if it runs cold, when potentially the food might get undercooked.
When I lived in Malawi, my oven was in centigrade. I suppose I could have done the math, but I ended up just approximating (as I recall, it was pretty inaccurate even in centigrade). It's certainly possible to cook without temperatures, but one will have over/undercooked food until one figures out what the temperatures are, more or less.
The oven should be preheated, but I agree that there's no point stressing about degrees. For me, there's low, medium, hot and very hot.
For some foods, like a roast, having the temperature be off by 25 - 40 degrees can be compensated for with more or less time.
But for many baked goods the oven temperature affects how quickly the food cooks on the outside versus the inside. A temp that is too high will make the outside brown before the inside is fully set, so you wind up with a crust that has to split to allow the inside to finish cooking (or you have a sturdy crust & a denser-than-desired middle). For cookies an oven temp that is too low can be disastrous - by the time the outside is golden brown the inside is drier than the Sahara desert.
If you want a cookie with a golden brown and slightly crispy exterior, but still a chewy center, temperature IS important. Even 25 degrees can be important. No one is saying you have to "worry" or "stress" - just be aware.
I do agree on the necessity of an instant thermometer, it can (!) be used for baked goods too, like bread and pies to see how hot the internal temp is. If it looks dark, cover it with foil, and keep baking until the internal is in the desired range. Goes for meat, casseroles, whatever. Takes all the guess-work out of different ovens, timing, convection vs not, etc. Still, use your visual & temperature cues to tweak the recipe to your equipment to get the best results. So "400-ish" was too high for what you wanted in your ideal bread? Too dark, too light? keep tweakin' it, until you get it just the way you want. As long as the middle gets done, you can change a lot in the external texture and appearance with oven temp.
I grew up in a house that rarely used recipes (unless a dish was being cooked for the first time), so I was taught to play it by eye and nose. If the dish required 350F, then we set the oven dial at 350F and assume it's 350F. Then we'll just check on it once in a while. If the dish turned out to be too pale or too dark, we would just adjust the temperature accordingly the next time we cook it.
I'm with Ambitious. We inherited a 15 year old capricious oven with our house, and it's generally off by about 25-50 degrees. I don't expect the temp to always be exactly constant, but the oven thermometer lets me know if it gets too hot and I need to turn it down a bit. Also, it's good to keep in mind that every time you open the oven door you can expect to lose 25 degrees of heat.
Who cares what cookbook writers did at the time when they started putting temperature dials on ovens? The cookbooks I have and use were written long after, and the recipes were tested at those temperatures.
I find the advice to disregard pretty ridiculous, too. Unless you have a new oven that works perfectly, which most of us probably do not, every apartment I've been in has had oven "issues," too hot or too cold. As someone said, for baking, that's pretty crucial and if you're following someone else's recipe for the first time, the difference between taking out cookies at 12 minutes or 15 minutes is huge. Same goes for chicken and other meat. In fact, when is it not important to check how hot your oven really is?