Muffins and quick bread, dips, and pies almost always start with the same instruction: “Preheat the oven to 350°F.” Why?
Why is that?
What makes 350°F the magical temperature?
Why is it that so many types of baked foods from cake to bread go in a 350°F oven and come out perfectly after a relatively brief bake?
The answer to that is one part science and one part, well, human laziness.
Putting something in a hot oven sets off a series of chemical reactions that turn the gooey dough into a bouncing bread or sheets of puff pastry into flaky pastries. A temperature of around 350°F is hot enough to complete a lot of these steps quickly.
Step 1. At 90°F, fats begin to melt and combine with the gluten proteins (flour). Gases from the baking soda or baking powder are released, which helps make the baked good tender.
Step 2..At 140°F, the gluten proteins (flour) begin to swell and dry out. That’s when cake or cookies go from wet batter to dry food.
Step 3. At 300°F, sugar starts to caramelize.
Step 4. The Maillard Reaction, a point at which foods begin to brown and develop their distinctive flavor, happens around 320°F.
So why 350°F? It’s good enough to make all those necessary steps happen quickly, even if your oven runs a little cold and it’s not so hot you have to worry about burning.
But how did we decide to bake things at 350°F and not 340°F or 360°F?
That requires a trip back to the turn of the century.
Before we had ovens that could be warmed up in 5-degree increments like we do today, we had ovens that could bake at three settings: slow, moderate, or high. Recipes for baked goods often called for “moderate ovens.”
After World War II, oven manufacturers capitalized on some technological improvements from the war. Newer models of ovens gave cooks slightly more control by letting them set their gas and electric ovens in 25°F increments. Today, many modern ovens will let you set your oven in 5°F increments.
Attempting to adapt antiquated recipe instructions to match the modern day appliances, recipe writers converted a “moderate” temperature to 350°F, which was typically halfway between an oven’s lowest setting, around 200°F, and its highest, around 500°F.
Is 350°F really the best temperature for baking?
No, probably not. Ovens are notoriously unreliable, so setting your oven to 350°F promises you’ll land somewhere between 330-370°F. You’ll hit 350°F only if your oven is well-calibrated. That being said, most ovens have hot spots and cool spots, so it’s not a good bet that you’re really cooking at precisely 350°F.
Recipe writers and food marketers know that it’s better to err on the side of caution with the “moderate” temperature than to get very specific and have a failed recipe.
Some baked goods, like crusty baguettes, benefit from baking at a higher temperature, but a too-high temp could sink it. The higher heat will help the bread rise more quickly and set the crust before the gluten in the bread has a chance to dry out and stiffen.
The same can be true for muffins: the muffin tops rise taller in the higher heat, and you can lower the temp to finish baking them and prevent them from drying out.
Likewise, many chocolate chip cookie recipes bake at a higher temp as high as 425°F or start hot and finish at a lower temp. The hot start gets the dough to the caramelization and Maillard Reaction stages faster and then slows the cooking down to keep the cookies from drying out or burning.
Until ovens become almost foolproof and manufacturers can guarantee an oven really is the temp it says, we’ll stick with the magical 350°F. It’s good enough to get the job done.
I like keeping an oven thermometer close at hand to check my oven temperature from time to time.