A thermometer changes what you are able to cook

Both approaches to kitchen thermometers work. What differs is what they cost you, and the cost is what this sets out.

Colour is a poor guide

Meat colour depends on pH, packaging, freezing history and the pigment content of the muscle, not only on temperature. Poultry can remain slightly pink at a safe temperature, and minced meat can brown before it is fully cooked. The touch test with your palm is a rough heuristic that varies with the cut and with how it was cooked.

Temperature is the only property that actually tracks doneness and safety, which is why guidance is written in degrees.

What to buy

An instant-read digital probe is the workhorse, and speed of reading matters more than any other specification. A leave-in probe with an external display is useful for large roasts and for bread, where you want to watch the climb. Infrared thermometers read surface temperature only, which makes them useful for pans and useless for meat.

If you are short of time, analogue dial thermometers are slow, often inaccurate and awkward to calibrate, and are a false economy.

Using it properly

Read the thickest part, away from bone and fat, since bone conducts heat differently and gives a misleading number. Push through and withdraw slowly, watching for the lowest reading, which is the true centre. For thin cuts, insert from the side rather than the top so the probe sits in the middle of the thickness.

Check more than one place in a large or irregular joint, because it will not be uniform.

Calibrate it occasionally

A probe in a slurry of ice and water should read close to zero degrees Celsius, and boiling water gives a second check adjusted for altitude. Many digital probes have a calibration function, and those that do not can simply be used with a known offset. Dropping a thermometer is the most common reason for it drifting, and it happens more often than people admit.

A thermometer you do not trust is worse than none, because it makes you second-guess a correct reading.

Beyond meat

Bread is done by internal temperature far more reliably than by tapping the base, and enriched loaves finish lower than lean ones. Custards, curds and caramel all have narrow temperature windows that are difficult to judge by eye. Oil temperature for frying is the difference between crisp and greasy, and it drops sharply when food goes in.

Dough temperature after mixing is the single most useful measurement in home bread baking.

Adjust seasoning at the end rather than trusting a quantity written by a stranger.

Safety guidance is national

Recommended safe internal temperatures for poultry, minced meat, pork and fish are set by national food safety agencies and differ between countries. Some countries publish time-and-temperature combinations rather than single numbers, since pasteurisation depends on both. Look up the figures for where you live rather than relying on a number remembered from a television programme.

For anyone cooking for pregnant people, young children, older people or anyone immunocompromised, the conservative end of that guidance is the sensible choice.

Side by side

The takeaway

Buy a fast digital probe, check it in ice water, and look up the safe temperatures for your own country.

Get the heat and the salt right and the rest is detail.