Why Food Temperature Matters

Old Cue: Simmering Water
New Cue: 160°F (meat and fish)/180°F (eggs)

Cooks often think of a simmer as just barely below a boil (which is not technically wrong, though "simmer" has a broad temperature range). But when you poach fish or chicken in liquid in the 180°F to 200°F range, they end up  tough and dry, because the high temps scald the meat and squeeze the life out of them. Instead, heat the water only to 160°F, which is closer to the end temperature you want the food to be (chicken breasts are ready at 160°F; white fish at 145°F; medium-cooked salmon at 125°F). When you gently submerge your food, the water temperature will drop immediately, so adjust the burner heat until the water comes back to 160°F. This approach yields incredibly supple and juicy proteins. Quick-cooking eggs need a higher temp and some bubbles, so 180°F works best for poaching them.

Old Cue: Toss in a spoonful of batter and see if it bubbles rapidly
New Cue: 375°F/340°F

Frying oil temps can range from 325°F to 400°F or so. For healthy frying, the oil needs to be hot enough to turn the food's water content to steam, which prevents the food from absorbing oil. Oil that's too cool will seep into the food, making a soggy grease bomb instead of crunchy, golden perfection. We find 375°F ideal for quick-frying veggies and dumplings, while 340°F is great for dense items like chicken and fish.

Old Cue: Until fork-tender
New Cue: 195°F

You've probably had overcooked pot roast. And strange as it seems, you can dry out stewed and braised meat, too, even though they cook in liquid. Cooked too long, the meat surrenders its juices and turns stringy. The sweet spot is said to be when you can insert a fork and easily pry the meat into shreds. But this leaves plenty of room for error. Tough connective tissue that binds cuts like pork shoulder, beef chuck roast, and lamb shanks is made up mostly of collagen, which starts to melt at around 140°F. When the meat reaches 195°F, the collagen has all turned to creamy gelatin that coats the meat and gives it seductively rich mouthfeel. The meat stays superjuicy at this temp, too. Recipes that calls for shreds of meat (like pulled pork) can go to 200°F for a little extra fal-off-the-bone tenderness without drying out.

Old Cue: Until browned and bubbly
New Cue: 155°F

Face it: The macaroni is just a vehicle for the rich, velvety cheese sauce. But lighter versions with reduced-fat dairy can curdle easily, and broken sauce kills this comfort food. Even whole milk and half-and-half curdle if cooked too hot or too long. The trick is to heat the sauce no higher thant 155°F, just enough to melt the cheese into the milk mixture. No need for the sauced mac to bake long in the oven—a few minutes under the broiler will brown any added topping nicely.

Old Cue: Mixture "thickens slightly" or "coats the back of a spoon"
New Cue: 165°F (sauce)/179°F (ice cream base)

The terror of making any egg emulsion (hollandaise sauce, carbonara pasta, mayo) is that the egg will overcook and curdle into a sad, coagulated mess. A custard like crème anglaise, the sweet base for crème brûlée and ice creams, is just as delicate. And even experienced chefs can differ on exactly what a slightly thickened custard looks like or how it should coat the back of a spoon. It's important to heat the mixture gradually, so it cooks evenly and doesn't scald. But for a sauce base, the only visual cue you need to guarantee perfect consistency is a read of 165°F on your digital thermometer. Then chill it down, and you're golden. Because a custard that will be an ice cream base needs to be a little thicker, we carefully take it to 179°F.

Old Cues: Temp range, touch test
New Cues: 115°F/81°F/89°F

To temper chocolate, you melt it down, then cool it back into solid form, giving it shiny gloss and snappy texture. Chocolate can be finicky, so precision is critical. Look to hit three marks during the process: first, 115°F when you melt the chocolate in a double broiler or the microwave; next, 81°F when you add whole chunks to cool the mixture, and last, 89°F when you reheat the whole mixture. This temp combo leads to Wonka-level magic every time.

Old Cue: Tap on the bottom of the loaf and listen for a hollow sound
New Cue: 200°F/185°F

Unless you're practiced in the art of bread loaf tapping, underbaked bread can make a very similar "hollow" sound to a fully baked loaf. It's like thumping a watermelon to check for ripeness: Do you really know what you're listening for? The thump test for bread works just fine for seasoned bakers, but the rest of us need a more exact guideline.

Our in-house baking experts find that at 200°F, yeast bread like baguettes, sourdough boules, and whole-grain loaves are ready to pull from the oven and cool. Sweet and egg-enriched breads like challah and brioche that are softer than "lean-dough" breads will be done sooner: Our bakers aim for 185°F. And to keep the loaf looking pristine, insert the thermometer into the bottom, if possible.

Old Cue: "Lukewarm" water, touch test, temp range
New Cue: 110°F

Active dry yeast is alive, made up of good-guy microbes that give rise (in every sense) to fresh-baked bread. The first step is to combine the yeast with water to proof, or "bloom," the yeast, bringing the microbes back to life. Old-school bakers will tell you to test the temp with your finger: Water that's about 98°F won't feel like anything at all, since it's approximately the same as your body temperature. They say the right temp of water will feel slightly warm to the touch, but this is pretty imprecise. Many recipes ofer a range as wide as 105°F to 115°F. We aim for dead center—110°, warm enough to activate the yeast but not too hot to kill it and allowing for 5 degrees leeway either way.