Published November 1, 2006.
We finally found an easy-to-use candy thermometer.
Candy thermometers are designed for stovetop recipes where close monitoring of temperature is key—especially candy-making and deep-frying. The thermometer stays in the liquid during cooking. But which brand is best? To find out, we brought several models into the test kitchen and made multiple batches of caramel for our Turtle Brownies.
Thermometers with the simplest style—a plain glass tube—worked fine, but they are also fragile and the gradations were hard to read. What's more, a few models had a tendency to slide down and touch the bottom of the pan, giving a false reading. Similar thermometers with a metal "foot" to keep the thermometer off the pan bottom didn't work in a small (shallow) batch of caramel and were also hard to read. Dial-face thermometers required as much as 2 1/2 inches of liquid—a rarity when making candies.
By far, digital thermometers are best: quick to respond, precise, and easy to read. Most digital models have easy-to-read consoles and alarm features that warn the cook when the caramel is done. But they tend to be top-heavy, with a precarious grip on the saucepan. The one we originally liked best had the most reliable grip, and it's a decent choice. But essential? Probably not. An good instant-read thermometer capable of registering temperatures up to 400 degrees is just as reliable and can also be used to check the temperatures of roasts, breads, sauces, and more.
Still, we wanted something more like our favorite thermometer for roasts in which a long wire separates the "brains" from the business end. Then we found a probe thermometer model that comes with a mounting clip that lets you attach the probe to your pan. An on/off switch would be nice (to save batteries over time), but it still gets our top recommendation for its clip-on ease.