Magazine article Sunset

Which Thermometer? It Makes a Big Difference

Magazine article Sunset

Which Thermometer? It Makes a Big Difference

Article excerpt

Which thermometer? It makes a big difference Correct temperature is critical to success in cooking. And whether you're aiming for a medium-rare roast, creamy fudge, or golden doughnuts, a reliable thermometer can help you judge the best conditions for cooking and when the food is done.

Walk into any store that carries cookware and you'll find thermometers of seemingly every description. There are ones for different categories of food, for regular or microwave cooking, for instant or conventional readings. Which suits your needs?

First, it helps to realize there are two basic types currently on the market: bimetal and glass column. (A third type--the digital probe--is expected on store shelves in the near future.) Within each category, different models are intended for certain uses, from double-checking oven temperature to tempering chocolate.

Here we give a complete rundown to help you select the right thermometer--and, on page 188, tips for getting the best results, based on our own experiences.

Bimetal: slow to fast

You can recognize bimetal thermometers by their dial face. The pointer in the dial connects to a spring made of two metals sandwiched together. When the temperature changes, each metal expands or contracts at a different rate, causing the spring to wind or unwind. Because of slight inconsistencies in the expansion or contraction rate, bimetal thermometers are best for uses where accuracy to the precise degree isn't necessary.

One asset is that the dials are generally easy to read; some are especially large, have magnifying covers, or come with adjustable red arrows on the rim to use as temperature locators.

Stand-mounted oven thermometers have a coil spring that reacts slowly to temperature changes so that briefly opening the oven door won't affect the reading. Stem-mounted food probes are faster, but their movement may be slightly jerky.

Instant-read thermometers, another bimetal type, have the dial mounted on a more slender stem that holds a faster-reacting spring. Most can't be left in the oven while food cooks (some models have parts that may melt), but their slim stem and quick response allow frequent use to check progress.

Most bimetal styles cost $3 to $7; instant-read models range from $10 to $15. All are relatively durable.

Glass: accurate but fragile

A thin glass tube holds colored liquid (usually nontoxic alcohol for food use), which expands up the tube as it heats. A scale alonside records temperature. Choose this style when accuracy and consistency are important. If the thermometer is placed in the food or oven as it heats, it can respond almost instantly.

Although some have a protective stainless steel shaft or sheath, the glass tube is fragile. If you heat the thermometer past its range, its top can blow off. If one is dropped, the liquid may get separated by an air bubble, making the readings inaccurate. Sometimes you can fix this by gently tapping the end on a flat surface.

Look for a thermometer that is securely attached to its scale. If it comes loose from its moorings, it is hard to reposition.

Because you need to read glass thermometers straight on to see the colored liquid, they are more difficult to read than most dial models. Cost is $8 to $10.

Digital probes: style of the future?

Already used in the food industry, digital thermometers with metal-resistance or thermocouple sensors provide very accurate, almost instantaneous readings. Several models for home-kitchen use are under development now. Some units may be built into ovens; others will be portable. Since temperature ranges will vary, watch for ones that suit your purposes.

Which thermometer for what use?

Keep this trade-off in mind: thermometers with wider temperature ranges are more versatile, but those with narrower ranges are more accurate and easier to read. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed


An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.