How to use a Maple Syrup Hydrometer
What is a Hydrometer?
A hydrometer is an instrument used to measure the specific gravity (or density relative to water) of a liquid. The
density of maple syrup is measured in Baumé degrees and fluctuates with temperature. At a temperature of 211 °
Fahrenheit, sap becomes syrup at 32 Baumé degrees. This hydrometer also contains a Brix scale, which
measures the sugar content of a liquid.
How to Use Your Syrup Hydrometer:
Fill the hydrometer test cup with syrup until it is approximately 2 inches from the top and place it on a level
surface. Do not fill the hydrometer cup with the hydrometer inside, as the syrup on the stem will add weight and
affect the reading. Slowly lower the hydrometer into the syrup until it is floating on its own or resting on the bottom
of the hydrometer cup. This is a very fragile instrument. DO NOT drop the hydrometer into the syrup, as this can
cause the hydrometer to shatter.
Reading the Hydrometer:
It is important to take a temperature reading at the same time as the hydrometer reading, because density
changes with temperature. Take the hydrometer reading once the hydrometer has stopped bobbing. Read the
Baumé scale on the hydrometer where the scale meets the syrup in the hydrometer test cup. Using the
conversion scale below, determine the desired Baumé degrees based on the temperature.
- If the Baumé reading is higher than desired, the syrup is heavy. Add some sap to the boiling syrup to
- If the Baumé reading is lower than desired, the syrup is light. Continue to boil the syrup.
Between readings, clean the hydrometer with hot water or sap.
Conversion Scale for Temperature Variation