What’s so magical about that number?
The magic of cooking at 350 degrees isn’t magic at all, but chemistry. It is, for example, the level associated with the Maillard Reaction, the chemical process that gives so many foods a complex flavor profile—and an appealing golden-brown hue—when sugar and protein are heated together just so.
“Without Maillard chemistry we would not have a dark bread crust or golden brown turkey,” wrote the authors of a Royal Society of Chemistry book about the reaction, “our cakes and pastries would be pale and anemic, and we would lose the distinctive color of French onion soup.” The Maillard Reaction—which actually entails a series of reactions—isn’t all toasty goodness, however. It’s also responsible for making apples turn brown, which many people find unappetizing “despite negligible effect on flavor,” the authors write.
Well, it turns out that oven temperatures weren’t nearly as precise before they had degrees on the dial, and it hardly mattered. They aren’t even that precise now. Cooks from bygone eras pretty much learned what worked by experience. If your oven was hotter or cooler, you just adjusted your baking time. An article at the Atlantic tells us about how precise oven temperatures came about, and why recipe publishers chose the settings they did. I use 400 degrees more often these days, since I’m putting something frozen in the oven.