Thermometers

By comparison with other technical issues around cooking, temperatures are relatively straightforward. There's the Celsius scale (water freezes at 0° and boils at 100°), and the Fahrenheit scale (water freezes at 32° and boils at 212°). The obsolete Réamur scale and the technical Kelvin scale are not used in cooking. Celsius is still frequently referred to as Centigrade, since it has 100 degrees between freezing and boiling.

Fahrenheit gets on my nerves because I'm not used to it, but it's relatively easy to convert to Celsius: C = (F - 32) * 5 / 9. When I feel like it, I might include a conversion table here.

The real problem with temperatures is that they're so seldom mentioned. What temperature should a roast beef be in the middle? Ask me and I'd say 58°. Ask others and they might talk in terms of the colour of the meat (not an easy thing to measure during cooking) or the length of time you cook “at gas mark 5”. But meat thermometers are available, even if the ones I have found in Australia recently have left much to be desired. Some are made of plastic (“do not place in the oven”). The best I've found looks like this:

The best thing about this thermometer is the warning at the bottom: Do not put in water. My old thermometer, made in Germany, does not have this inscription:

Since writing the above, I've found a digital meat thermometer:

It's useful (and not overly expensive), but it's not easy to use. The temperature probe (in front) is coated with metal, and it is connected with a wire braid. I presume that the sensor itself is at the tip of the probe, but the metal cover is a good conductor of heat, and as a result it tends to show higher temperatures than you'd expect. That's why I've wrapped some stiff paper around it, to insulate it from the outside. A ceramic covered probe would be much better. It would also have avoided the fate of this particular unit: I put the probe in a barbecue with the lid down, and it fried the probe (presumably the cable). I need to find a better unit.