The Bimetallic Stemmed Thermometer

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A bimetallic stemmed thermometer is an important tool for keeping track of food temperatures. 

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Using a Bimetallic Stemmed Thermometer

These thermometers usually measure temperatures from 0º F to 220º F. Check the metal stem for a notch or slight indentation as an indicator of how far into the food the thermometer must be placed to take an accurate reading.

Step 1: Calibrate the thermometer  
Step 2: Clean and sanitize thermometer (an alcohol wipe or sanitizer dip may be used)
Step 3: Air dry thermometer
Step 4: Insert into food up to the indicator notch
Step 5: Take reading when dial stops moving
Step 6: Clean and re-sanitize thermometer
Do not leave thermometer in food while it is cooking. 
 

Calibrating a Bimetallic Stemmed Thermometer  

A thermometer is your best defense against temperature abuse. However, it is of no use if it is not measuring the temperature of food accurately. You should calibrate your thermometer any time you have used it in a very hot to very cold food, it’s been dropped, or if it does not appear to be taking accurate readings.

Boiling Point Method:
Use this method in locations where altitude does not affect the boiling point temperature. Place metal stem thermometer into boiling water. When the recording needle stops moving, read the dial. It should read 212º F. If this is not the reading, then, while keeping the thermometer in the boiling water, adjust the calibration nut at the base of the dial until the needle is at 212º F. Wait another 15 seconds to be certain it maintains a temperature of 212º F. 

Freezing Point Method:
Place the metal stem thermometer into a container of crushed ice and water. When the recording needle stops moving, read the dial. It should read 32º F. If it does not, then, while keeping the thermometer in the ice water, adjust the calibration nut at the base of the dial until the needle is at 32º F. Wait another 15 seconds to be certain it maintains a temperature of 32º F. 

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Phone: (603) 447-3834
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