Illinois Food Service License Practice Test

The correct answer is that a bimetallic stemmed thermometer must be inserted up to the dimple in the thermometer stem to provide an accurate reading. The dimple marks the point where the sensing portion of the thermometer begins, ensuring that the measurement is taken at the correct depth where the temperature of the food is accurately detected. This is crucial for safety in food service, as improper readings can lead to undercooked food that poses health risks.

Inserting the thermometer deeper than the dimple may not affect the reading; however, it risks measuring the temperature of the surrounding material rather than the food itself. Simply touching the tip of the thermometer to the food does not provide an accurate reading, as the temperature may not stabilize due to insufficient thermal contact. Thus, proper insertion up to the dimple is essential for reliability in temperature readings.