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Types of Thermometers

Food Thermometers

Food Thermometers
Types	Speed	Placement	Usage Considerations
Digital Thermometers
Thermocouple	2-5 seconds	1/4" or deeper in the food, as needed	gives fastest reading good for measuring temperatures of thick and thin foods not designed to remain in food while it’s cooking check internal temperature of food near the end of cooking time can be calibrated more costly; may be difficult for consumers to find in stores
Thermistor	10 seconds	at least 1/2" deep in the food	gives fast reading can measure temperature in thin and thick foods not designed to remain in food while it’s cooking check internal temperature of food near the end of cooking time some models can be calibrated; check manufacturer’s instructions available in "kitchen"stores
Oven cord thermometer	10 seconds	at least 1/2" deep in the food	can be used in most foods can also be used outside the oven designed to remain in the food while it is cooking in oven or in covered pot base unit sits on stove top or counter cannot be calibrated
Thermometer fork combination	2-10 seconds	at least 1/4" in the thickest part of food	can be used in most foods not designed to remain in food while it is cooking sensor in tine of fork must be fully inserted check internal temperature of food near the end of cooking time cannot be calibrated convenient for grilling
Dial Thermometers
Oven-safe, Bimetal	1-2 minutes	2-21/2" deep in the thickest part of the food	can be used in roasts, casseroles, and soups not appropriate for thin foods can remain in food while it’s cooking heat conduction of metal stem can cause false high reading some models can be calibrated; check manufacturer’s instructions
Instant-read, Bimetal	15-20 seconds	2-21/2" deep in the thickest part of the food	can be used in roasts, casseroles, and soups temperature is averaged along probe, from tip to 2-3" up the stem cannot measure thin foods unless inserted sideways not designed to remain in food while it is cooking use to check the internal temperature of a food at the end of cooking time some models can be calibrated; check manufacturer’s instructions readily available in stores
Other
Single-use Temperature Indicators	5-10 seconds	approx.1/2" deep (follow manufacturer’s directions)	designed to be used only once designed for specific temperature ranges should only be used with food for which they are intended temperature- sensitive material changes color when the desired temperature is reached
Liquid-filled (glass or metal stem)	1-2 minutes	at least 2" deep in the thickest part of the food	used in roasts, casseroles, and soups can remain in food while it’s cooking cannot measure thin foods some can be calibrated; check manufacturer’s instructions possible breakage of glass stem while in food heat conduction of metal stem can cause false high reading

Appliance Thermometers

Refrigerator/ Freezer Thermometers:

For safety, it is important to verify the temperature of refrigerators and freezers. Refrigerators should maintain a temperature of 40°F or below. Frozen food will hold its top quality for the longest possible time when the freezer maintains 0°F or below. An appliance thermometer can be kept in the refrigerator and freezer to monitor the temperature. This can be critical in the event of a power outage. When the power goes back on, if the refrigerator is 40°F or below, and the freezer is still colder than 40°F, the food is safe. These bimetallic-coil thermometers are specially designed to provide accuracy at cold temperatures.

Oven Thermometers:

An oven thermometer can be left in the oven to verify that the oven is heating to the desired temperatures. These bimetallic-coil thermometers can measure temperatures from 100 to 600°F.

Pop-Up Timers:

Commonly used in turkeys and roasting chickens since 1965, the "pop-up" style disposable cooking device is constructed from a food grade nylon. The inside contains a stainless steel spring and organic firing material. The organic firing material is specifically designed to dissolve at specific predetermined temperatures. Once the firing material dissolves, the stainless steel spring releases the stem, allowing it to "pop up." This indicates that the food has reached the correct final temperature for safety and doneness. Pop-up style disposable cooking devices are reliable to within 1 to 2°F, however, proper placement is important. Checking with a conventional food thermometer is always recommended as an added precaution to properly gauging both safety and doneness.

Candy/Jelly/Deep Fry Thermometers:

These thermometers will measure temperatures ranging from 100 to 400°F. They are used to measure the extra-high temperatures required of candy and jelly making, as well as frying with hot oil.

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