To preheat or not to preheat, that is the question

June 27, 2023·Darcie

Almost any baking recipe, savory or sweet, begins with instructions to preheat the oven. It's second nature for most cooks to turn on the oven before gathering ingredients or preparing baking pans. But is it really necessary to preheat? There's one school of thought that says it wastes time and electricity (or gas), and another that says you need to bring the oven to temperature for even cooking. Food & Wine is in the latter camp, and they also provide tips on how to properly manage your oven temperature.

Food & Wine says preheating is a must because as the oven heats up, the "temperature fluctuates, creating significant spikes and drops in heat" that can mess with the look and consistency of your baked goods. They also go a step farther to say that you should preheat some cookware, especially Dutch ovens used to bake bread. Additionally, many - if not most - ovens use both the upper and lower elements when preheating but only the lower element to maintain the temperature. Having the top element on can lead to over browning the top of your food, especially if the oven rack is in any of the upper positions.

Food safety experts also say preheating is an important step, because it reduces the amount of time food lives in the "danger zone" of 40 to 140 degrees Fahrenheit. Even if the time to preheat your oven is not very long, the experts remind us that "some bacteria can multiply in the danger zone in as little as 20 minutes."

The counter arguments fall into two main camps. The first camp says that it is simply not necessary to preheat the oven for many items, especially those with a long cooking times (think baked potatoes) or that have a lot of liquid, like stews. The second camp says that preheating wastes energy. Even if you have to cook the dish a little longer, the savings amount to about 10% less energy being used, depending on the recipe. Saving 10% may not be life changing, but it is significant enough to consider. A handful of recipes even dictate that you begin with the oven off, the most common being cold oven pound cake and cold oven roast chicken.

Like most things in life, it seems that there is not a black-and-white or one-size-fits-all answer to the question of whether to preheat or not. It will depend on what you are cooking and how your oven heats up. There is one thing that all of the experts agree on, however, and that is to invest in an oven thermometer so you know what temperature your oven really is when you set it to 350 F/180 C.

7 comments

gamulhollandJune 27, 2023

For anything but baking, I usually just pop it in the oven and turn the oven on— no preheating. But baking is such a science — I definitely preheat for baking, but rarely as the first thing even though it’s usually the first instruction, because I’m not that fast and typically the oven is ready long before I am. So that’s how I strike a balance. :)

westerJune 28, 2023

I never preheat anything, not even the three minutes the air fryer wants. But then, I never bake, it might matter then.

FyretiggerJune 28, 2023

There really isn't a single answer to this question. Try making popovers without the thermal shock provided by a preheated oven and pans. Try oven roasting bacon without the fat rendering provided by starting with a cold oven. There are times it matters in both directions, and there are times it doesn't.

Pardon my skepticism, but anyone who is advocating for a one-size-fits-all solution on the matter either has an agenda (in food writing, it's probably coming up with an article for the next deadline -- and they might argue the total opposite in 6 months for the same reason) or they are they are being intellectually lazy and arguing a position from a "my common-sense tells me..." stance, without actually testing their position.

The food safety arguments for preheating are frankly laughable -- so it's better to leave my food on my 70º counter for 10 minutes while the oven preheat, than it is to put it into a 70º and rising oven for that same 10 minutes? I'd like to see the lab data proving that preheating results in lower bacteria counts at the end of cooking.

ellabeeJune 28, 2023

Ovens vary so much in size, technology (gas/electric/convection), location of burners, etc. I'd be very interested in an overview that assessed the pluses & minuses for different kinds of cooking.

CapeCodCookJune 28, 2023

I am a fan of preheating for most recipes—and always for baking—mostly because my cookbook recipes specify their cooking times starting with a preheated oven and this is useful when timing the planning of my meals. However, I have learned NOT to trust the oven-beeper that tells me the oven-temperature has been reached—because it rarely has, even in my newish GE Profile oven. I wondered why most of my recipes always took longer to cook "till done" and when I started using a new oven thermometer inside it, I discovered that my oven was never up to temperature when it beeped to tell me it was! I wondered why my oven seemed so slow and recipes took 10-15 minutes longer to cook. My advice: ALWAYS use a reliable oven thermometer if you are preheating, or cooking anything for that matter.

reader1treesJune 29, 2023

I generally agree with all the other comments here and especially with CapeCodCook about buying and using an oven thermometer. One thing I do to save a little bit of energy is to turn the oven off 5 mins before the end of the cooking time for dishes like lasagne where I'm sure they're cooked through. Those last few minutes in the oven are just for browning the top and provided you don't open the door the oven stays hot for ages.

Xyz123June 29, 2023

I recently starting baking my sourdough bread without preheating. It works perfectly! I learned this method from Elaine Boddy
Whole Grain Sourdough at Home.