Here's one to keep you up at night: does it really matter if you rotate a pan of cookies in the oven while baking? The argument is that hot spots in the oven will cause cookies (or brownies, bread, pie, etc.) to bake faster in some places than others, and rotating the tray helps everything cook evenly. But we're not convinced.
The counter argument is that opening the oven door lets out a surprising amount of heat, even when you're just quickly reaching in to rotate a pan. The drop in temperature could also cause baked goods to cook unevenly as the warm air sweeps out and the heating units blast on to correct the temperature.
By our thinking, if we just leave the oven door closed, the heat will even itself out. The fact that it's a closed system means that less heat will be lost and the heating units will come on less frequently. At least theoretically.
We've been experimenting in our oven with the two things we make most frequently: bread and chocolate chip cookies. So far we've found no real difference between either rotating the trays or letting them be. Then again, our oven in a previous apartment - an admittedly very old oven - was very definitely hotter in the back and we often ended up with slope-shaped loaves of bread.
Maybe it comes down to your own oven and figuring out what works best. What do you think?
Related: Why Do My Baking Sheets Buckle in the Oven?
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Comments (15)
Keep the door closed! Especially if you have a less expensive oven that loses a lot of heat.
Convection ovens get rid of the hot spot problem, making this question moot. I love to bake at my parents' house because their convection oven cooks everything so evenly!
http://operagirlcooks.com
I'm a turner-round kinda girl... but I blame that on the terrible oven (http://penguinsandparentheses.blogspot.com/2010/05/four-letter-words.html) at my apartment. I never used to be quite so worried about turning when I lived with my folks (I quite understand, Coco... everything I cook at their place rises twice as much!)
I've always been a bit wary of rotating trays. I do it because recipes say to do it, and I understand all of the benefits of turning the trays, but have always thought that it prolongs the baking process since the oven has to come back up to temperature.
Depending on what I'm baking, I'll turn the trays/dishes, but if I want to save time, then I don't. I can't say that I've ever had anything drastic happen because I didn't rotate a baking item.
I always have to turn my sheets because cookies, bread, basically anything I am baking will burn at the back of the oven if I don't. Cookies will be completely uncooked in the front and burnt in the back. I have a really old crappy oven. I combat the lost heat with a pizza stone that I keep on the lowest rack which keeps a lot of heat in the oven when I open it.
I think it really depends on your oven. With my old oven - I definitely had to rotate, otherwise the ones in the back would get overbaked when the ones in the front were just barely done. If I rotated, it was okay.
With my new oven, it's not as important. It's still not perfectly even and I do sometimes get one side browner than another, but most of the time I can just leave it closed.
So, the moral is - know your oven (and get an oven thermometer)!
It depends on what I am cooking. Pies, definitely rotated; cookies, not so much. Anything that I need to check doneness for (and actually remove it from the oven) I usually attempt to rotate. I guess it's hit or miss with me...
I'm with digigirl: Totally depends on knowing your oven. If I don't rotate in mine, one side of the cookie sheet burns before the other is fully baked. Crappy-ass old oven, cheap-ass landlord. Plus if my oven thermometer is to be believed (the internal one I bought, not the gauge on the oven itself), there's not much heat loss in the few seconds it takes to turn--certainly not enough to affect baking time.
I never rotate pans in the oven and haven't noticed problems. Maybe I'm lucky with a nice oven.
I think rotating hasn't been necessary since back in the day (like the 50s) if your oven is made in the past quarter of a century, I really don't think its necessary. My grandma's oven when I was young had hot spots and yes ovens now still have them but not enough to throw things out of whack.
Know thy oven. Pure and simple, as other commentors have said. There is no other answer.
Never trust your oven and always have an oven thermometer. My old oven was much larger and the back was hotter than the front. My new oven is much more compact and pretty much even throughout, so I am going to try not rotating and see what happens.
In previous ovens, I always had a pizza stone in the oven, which helps to even out hot spots. Now, I also have a good stove, with convection oven, so this is no longer an issue.
What's up with comments? On main page it says this has 12 comments but when I open it there are none.
Anyway, life's too short to rotate baking pans. Maybe for a lemon meringue pie...
Even convections cook unevenly. We have a nice convection oven at work and after about 8 minutes we rotate the cookies and other items. Why? Because you can see browning on one side and the other side is pale.
A little baking science: when it comes to opening the oven, you must keep the door closed for the initial few minutes of baking because of something called "oven spring". Smaller items take about 8 minutes (cookies), but cakes, 10-14 minutes (or longer, depending on size). This is when the initial heat reacts with the baking powder/soda, yeast, or egg whites, which causes the batter and dough to rise and it sets the structure during this time. So if you open the door too early, you will get a rush of cool air in which causes your baked goods to fall in the center. You can't get this rise back; the rest of the baking time will just cook the center.
It would be nice to have the perfect oven to bake everything evenly. If you have success rotating, then that's good. If not, then that's fine as well.
Hope that helped.
What ARE those cookies in the picture? They look awesome!