Ensuring food is prepared to the correct temperature should not be a matter of guesswork; the experienced chef will be able to tell if a dish is correctly heated through, but the more inexperienced cook can greatly benefit from a food thermometer. From the practical point of view, making sure food is cooked to a safe temperature – one at which dangerous bacteria will be destroyed – is a sensible precaution. Food thermometers are not exclusively used in the cooking of food, though; fridge thermometers are also available and are primarily used to ensure that raw and cooked foods are stored at safe temperatures.
About Food Thermometers
The word thermometer originates from the Latin words thermos, meaning hot, and metron, meaning measure. The two elements of a thermometer are the temperature sensor, such as the bulb in a mercury-on-glass thermometer, and a means of converting this into a numerical value, such as a visible scale. Thermometers work by using materials that change in some way when they are either heated or cooled. In a mercury thermometer, for example, the liquid expands when it is heated and contracts as it cools. The thermometer was not a single invention but the result of a series of developments. Galileo Galilei is often credited with pioneering work in this area; however, in 1593, he actually produced the thermoscope. The thermoscope detects changes in heat, but does not have a scale. Italian Santorio Santorio produced the first thermoscope with a scale – and thus the first thermometer - in 1612. Today, many different types and styles of thermometer are available. These range from medical thermometers, such as oral and forehead thermometer strips, to food thermometers such as meat thermometers and sugar thermometers.
Choosing a Food Thermometer
Some food thermometers are used simply to display the temperature of food in the oven. As ovens can vary in temperature, this is useful to know and will remove the need to estimate the temperature and the cooking time required. Others have a more specialist function, especially those that are designed for use in the making of confectionery and preserves, or for the heating of specific ingredients to a precise temperature. Food thermometers can also be used to ensure that cooked food is kept at a safe temperature until it is served.
Meat thermometers are used to ensure that the temperature of a piece of meat is elevated sufficiently in the cooking process to destroy potentially harmful bacteria and to reduce the risk of food poisoning. A long prong is inserted into the centre of the piece of meat or poultry and registers the temperature inside the joint or bird. This will guarantee the correct temperature is reached and the meat or poultry is cooked all the way through, ensuring that the middle is not undercooked. A digital display or analogue gauge will clearly show the cook the temperature inside the food and allow for an accurate calculation of the cooking time to be made. Research has shown that food and colour changes are unreliable when used to determine if food is cooked. The only way to ensure that any harmful pathogenic microorganisms present in the food are destroyed is to use a food thermometer. Meat should also be rested for at least three minutes before it is carved or eaten.
Professional confectioners and amateur sweet makers alike know the importance of bringing sugar up to the correct temperature, as too low or too high a temperature can ruin a whole recipe. With practice it is possible to estimate the temperature, but a sugar thermometer can take the guesswork out of it and help cooks to make perfect sweets. Sugar thermometers come in a range of styles, from the traditional flat metal type to the more modern digital versions. All can be inserted into the pan of ingredients to give a clear readout of the temperature, which enables chefs to proceed to the next stage of preparation once the required temperature has been reached. Digital sugar thermometers tend to be more accurate and some even have an alarm when a certain temperature is reached. The sugar thermometer reaches much higher temperatures than the meat thermometer.
A specialised item, the milk thermometer is designed to test the temperature of milk for making frothy coffees and can help the aspiring barista to make the perfect latte or cappuccino. The milk thermometer often comes with a clip to attach it to the milk jug. The ideal temperature for frothing is between 65ºC and 77ºC. Some milk thermometers have coloured zones to facilitate easy reading.
These items are used inside appliances in order to get an accurate reading of the current temperature.
Useful for ensuring the correct temperature for recipes that require precision, the oven/grill thermometer will display an accurate reading of the temperature inside ovens or grills, which can vary in temperature by a surprising amount. Ovens maintain temperature by cycling on and off, but even the best ovens often deviate from the desired temperature by several degrees.
Similar to the oven version, the refrigerator thermometer sits inside the fridge freezer to confirm the temperature and to ensure the safe storage of food. Not many refrigerators show the actual temperature; using a thermometer will allow the settings to be adjusted if necessary. Remember that food can spoil if a refrigerator temperature is too high; if it is too low then it will be using unnecessary electricity. Food-borne illnesses are a concern if the refrigerator is not cold enough.
Food Thermometer Styles
Food thermometers are available with analogue – commonly known as 'dial thermometers' – displays and digital displays.
Dial Food Thermometers
Dial food thermometers, also known as bimetal thermometers, are exactly as the name suggests: the temperature is shown on a dial, similar to a clock face. The dial food thermometer is more robust than the in-glass food thermometer.
Digital Food Thermometer
Digital food thermometers have electronic displays and are very easy to read. They often display the temperature with great precision and are compact and stylish. Digital food thermometers are the most common type of food thermometer, especially since concerns were raised over the mercury in the original in-glass thermometers.
Find a Food Thermometer on eBay
Potential buyers should take some time to prepare before entering into an auction; having a general idea of the current market value of the item they are interested in will ensure the final price they pay is realistic. Also, being aware of the types of food thermometers on offer in shops and on the internet will give customers an idea of which particular style best suits their need, and this can help reduce the time it takes to search for an item through the auction listings. Identifying their own needs is important, too; knowing the use to which the thermometer will be put can also save time and effort. Using the search tools available on eBay will make finding the right thermometer simple. One route is to use the dynamic menu on the homepage and follow the link through Home & Garden to Kitchen, and then to Food Preparation & Tools. This will open a page that contains a panel on the left hand side, which will contain a link to thermometers. Making selections in the category panel can further narrow the search. Another way is to type ‘food thermometer’ into the search box on the homepage and then select from the options in the drop-down menu. This is easier if the specific type of thermometer being sought after is known. Clicking on any of the options will direct the search to a similar page to that described above, and the category list in the left-hand panel can be used in the same way to find specific examples of the items required.
For the safe preparation of food, or for accuracy when making recipes that require exactness, a food thermometer can relieve the cook of the responsibility of guessing if food is cooked thoroughly. The food thermometer can also ensure that food is stored at the correct temperature. The selection of food thermometers on eBay offers something for every chef, however adventurous they may be.