To make sure the proper food temperatures are reached and maintained, you should use a probe thermometer. A probe thermometer is a thermometer that has a pointy metal stem that can be inserted into food. Use a probe thermometer to check internal food temperatures when you cook, re-heat, cool, thaw, and keep foods hot or cold.
There are different types of probe thermometers. Some are safe to use in an oven while others are not. Some provide instant digital readings while others use a dial to show the readings. Make sure you read the manufacturer’s instructions on how their thermometers work. Unless the thermometer is oven safe, never leave the thermometer in food that’s being cooked in an oven or on a stove.
Probe thermometers must be cleaned and sanitized by using alcohol swabs or a sanitizing solution after each use. To sanitize, mix 5 ml (1 tsp) of unscented bleach with 750 ml (3 cups) of water. Sanitizing the probe thermometer will help you avoid cross-contamination.
- Insert the stem of a probe thermometer into the thickest part of the food, or in the centre of the food if the food is even in thickness. If the food is liquid (e.g., stew or soup) stir it to make sure the heat has been evenly distributed before inserting the thermometer in order to get an accurate temperature reading.
- Wait at least 15 seconds for the reading to steady and then record the reading.
Don’t let the probe touch the bottom or sides of the food containers, because you won’t get an accurate temperature of your food.
“Recalibrating” means to adjust the thermometer to make sure it’s reading the right temperature. You need to recalibrate your thermometer regularly to make sure your temperature readings are accurate.
A thermometer should be recalibrated:
- Before first use.
- At least once a month.
- When the thermometer is exposed to extreme change in temperature during storage.
- If the probe thermometer has been dropped.
We recommend ice point method to calibrate your probe thermometer as it’s safe and easy to use.
- Fill a cup with crushed ice and add just enough water to barely float the ice. The temperature of the ice water will always be 0°C (32°F). This is the temperature that you use as a guide to calibrate your probe thermometer.
- Place the stem of the thermometer in the mixture, making sure it doesn’t touch the sides or the bottom of the cup. Wait until the needle stops moving. If the needle is not pointing at 0°C (32°F), it needs to be adjusted.
- If your thermometer has a calibration nut, use a small wrench to turn it until the temperature reads 0°C (32°F). Keep the probe in the ice water to make sure the temperature is accurate.
- Some thermometers, like the ones from the Windsor-Essex County Health Unit, can be adjusted in the same way by using its built-in wrench, while other types of digital probe thermometers can’t be recalibrated. Make sure to read manufacturer’s instructions to find out if your digital thermometers can be recalibrated.
Infrared thermometers (laser thermometers) are convenient to use. They give you an instant reading of the surface temperature of food or ambient temperature of the room, such as a cold storage unit. However, it’s not effective when checking the internal food temperature as the infrared light does not penetrate the food. Most of infrared thermometers can be calibrated. Please follow the manufacturer’s instructions for proper calibration.
If you have any questions, feel free to contact us at 519-258-2146 ext. 4475.