Milk thermometers, like any analog thermometer, need occasional calibration adjustments. We normally recommend checking accuracy every few months, but depending on the volume of your operations, you may prefer to check accuracy more often. If your thermometer has been subjected to any heavy use or abuse, it is important to recalibrate it immediately.
How to Calibrate Milk Thermometers?
The quickest way is to put both digital and analog thermometers together in a glass of hot water (close to boiling point). Wait 60-90 seconds for the water temperature to stabilize, then check the analog thermometer reading against the digital reading. If there is a difference, you will need to recalibrate. As a general rule, a variation of +/- 35.6°F/2°C is considered correct on most analog thermometers.
It is always preferable to control several different temperatures during the calibration process, such as 167°F/75°C, 104°F/40°C, and 50°F/10°C (or approximately). Cold water can be added to a simmering glass of water for a faster temperature change! This will ensure that the thermometer reads accurately across the entire temperature scale.
Remember to wait 60-90 seconds for the temperature to stabilize before comparing the readings.
Calibrate using the 'Ice Bath' method: Put crushed ice in a glass or milk jug, add cold water until it has a watery consistency. When the consistency is just right, mix the ice and water mixture for 30-45 seconds and then let it sit for another 2-3 minutes to allow the temperature to stabilize.
Calibrate using the 'Boiling Water' method: Boil a pot of water and use it as a guide for the 212°F/100°C mark. If you are using water from the kettle of the coffee machine, please note that the hot water does not disperse at its boiling point (212°F/100°C). Avoid using this as a guide.
If the problem indicates a difference between analog and digital thermometers, a simple recalibration can be done (this usually takes a few minutes).
When There Is A Difference Between An Analog And A Digital Thermometer, How To Fix The Difference?
- Simply adjust the needle position to show the correct temperature using a small wrench/wrench.
- While holding the dial/face, lock the tool into the recalibration nut on the back of the dial.
- To increase the temperature; Turn the recalibration nut clockwise.
- To reduce the temperature; Turn the recalibration nut counterclockwise.
This setting may take a few tries to get the needle to the 'perfect' position, but the ability to recalibrate 'with a flick of your wrist' provides an important key to extending the life of your analog thermometer.
When you are ready to calibrate using the Ice Bath or Boiling Water method, insert the thermometer into boiling or ice water and adjust the temperature readings accordingly using the adjustment method (described above).
If you want you can use both methods and transfer the thermometer from ice water to boiling water (and/or vice versa). Align the needle at 212°F/100°C if using boiling water or 32°F/0°C if using freezing water.