Use a Food Thermometer Correctly for Safer Everyday Cooking

Our Best Recipe Editorial Desk

A chicken breast can look done on the outside and still be underdone in the middle. That is why public-health agencies keep returning to the same tool. The CDC states that color and texture are not reliable signs that meat and poultry are safely cooked, and recommends checking with a food thermometer. The tool is inexpensive and simple, but a reading is only useful when the thermometer is accurate and the tip is in the right place.

Know which kind you have

Penn State Extension describes two broad categories for food use. A bimetallic stem thermometer has a dial on top and senses temperature along a length of the stem; it needs to be inserted to the dimple mark on the stem and usually takes at least 15 seconds to settle. A digital or instant-read thermometer senses at or near the tip and reads in roughly 2 to 10 seconds, which makes it better suited to thin foods such as burgers. North Carolina State Extension also describes thermocouples, which sense near the tip. These categories overlap, and response time, insertion depth and oven suitability depend on the model; follow its instructions.

The practical difference is placement. If your thermometer senses along the stem, a thin food cannot cover the sensing area, and the reading will be misleading. If it senses at the tip, you can measure a thin patty by inserting the probe from the side.

Put the tip in the right spot

Both extension sources give the same core instruction: measure in the thickest part, or center, of the food, and check in more than one place. Avoid touching bone or the pan, which can throw off the reading. For a casserole or a thick dish, the center is usually the last part to heat. Check more than one location and assess each piece that may have cooked differently. One acceptable reading does not establish that every part of a batch is safe.

Hypothetical example: a cook roasting several chicken thighs of different sizes checks the largest one first, near the center and away from the bone, then checks a second piece. Any piece short of the target needs more cooking and another temperature check before serving; do not judge all pieces by the one that cooked fastest.

Know the numbers

The CDC and FDA list the same core targets for home cooking. Whole cuts of beef, pork and lamb, such as steaks and roasts, should reach 145°F, and the FDA adds a three-minute rest time before carving or eating. Ground beef, pork and lamb should reach 160°F; ground poultry still needs 165°F. Poultry, whole or ground, should reach 165°F. University of Nebraska-Lincoln Extension advises reheating leftovers to 165°F as well.

These are minimum safe temperatures, not recommendations about texture. A recipe may describe a doneness preference, but for meat and poultry the thermometer reading is the safety check. For foods not listed here, use the federal safe minimum temperature chart for that specific item rather than guessing.

Check accuracy with ice water

A thermometer can drift, especially after being dropped. Penn State Extension describes the ice-water check: fill a glass with crushed ice, add water, stir, and hold the stem in it without touching the sides or bottom. An accurate thermometer should read 32°F. NC State suggests letting it sit in the slush for several minutes. Many dial thermometers have a calibration nut under the head that can be turned until the reading is correct.

Penn State notes that many digital thermometers cannot be adjusted. NC State suggests that if a digital unit reads wrong, try a fresh battery first; if it is still off, have it serviced or replace it. A boiling-water check is another option, but Penn State points out that the boiling point drops as elevation rises, so it is only a clean 212°F reference near sea level. Check the accuracy specification and calibration procedure for your own model, and do not rely on a unit that fails its required accuracy check.

Clean it every time

A probe that goes into raw meat can carry germs to the next food it touches. Penn State and NC State both say to wash, rinse and sanitize the food-contact stem according to its instructions before and after use; a stem used to check raw poultry should be cleaned before it goes into anything else. Keep the electronics dry unless the unit is rated for immersion. Store the thermometer where it will not get knocked around, since a hard knock can be enough to affect calibration.

Common mistakes

Reading too soon can produce an unstable or misleading result. Measuring near the surface, or with the tip touching a hot pan, gives a reading that is higher than the center of the food. Checking only one piece from a batch assumes they all cooked evenly. And trusting an old thermometer without ever testing it means you are trusting a number nobody has verified.

When to stop and reassess

Different readings can reflect real uneven cooking. Reposition the probe and follow the manual's response time. If the instrument's accuracy remains doubtful, check it with the manufacturer's recommended procedure before relying on it. If food is cooked for people at higher risk, such as young children, older adults, pregnant people or anyone with a weakened immune system, it is worth being especially careful about reaching and verifying safe temperatures, and asking their health care provider about any additional precautions.

A thermometer turns a guess into a measurement. Learn your type, put the tip where the heat arrives last, test it now and then, and wash it every time.

Sources

Penn State Extension, Thermometer Use and Calibration: https://extension.psu.edu/thermometer-use-and-calibration NC State Extension, Measuring the Heat (FSS5): https://content.ces.ncsu.edu/measuring-the-heat CDC, Preventing Food Poisoning: https://www.cdc.gov/food-safety/prevention/index.html U.S. FDA, Safe Food Handling: https://www.fda.gov/food/buy-store-serve-safe-food/safe-food-handling University of Nebraska-Lincoln Extension, Leftover Food Safety: https://food.unl.edu/article/leftover-food-safety