ABV via Ebulliometry

This method of finding ABV uses a piece of equipment called an ebulliometer. Water has a boiling point but alcohol has a lower boiling point. By finding the boiling point of a sake sample and comparing it to the boiling point of water you can figure out how much alcohol is in your sake.

Water will boil at different temperatures depending on atmospheric pressure. It is essential to take a baseline temperature of distilled water before testing a sake sample.

Sake has a high content of alcohol and this can affect the reading of the ebulliometer. To account for this a simple 1:1 dilution can be done and the results adjusted by doubling it.

Glucose content can also affect the reading of the ebulliometer. A correction can be applied by finding the Baume (see below).

Needs:

Method:

  1. Baseline Test with Distilled Water
    1. Flush the Ebulliometer chamber with distilled water
    2. Measure out ~100ml of distilled water and add to the chamber
    3. Turn on flow of cooling water
    4. Turn on Ebulliometer and allow to come to a boil
    5. Record the baseline temperature once the temperature has stabilized
  2. Sake sample test
    1. Flush the Ebulliometer chamber with distilled water
    2. Measure out 50ml of sake sample and mix with 50ml of distilled water
    3. Flush Ebulliometer chamber with sake dilution
    4. Measure another 50ml of sake sample and mix with 50ml of distilled water
    5. Fill Ebulliometer chamber with sake dilution
    6. Turn on flow of cooling water
    7. Turn on Ebulliometer and allow to come to a boil
    8. Record the sake sample temperature once the temperature has stabilized
  3. Subtract the two numbers and compare the result on the chart to find the ABV, then double the ABV percentage to account for your dilution

Correction for glucose:

  1. Calculate the Alcohol by following the above procedure.
  2. Using a Baume hydrometer determine the Baume reading of  your sake sample. The Baume must be >0.5 for the conversion to be applicable.
  3. Adjust the result by applying the following method:
    • Final Alcohol = Apparent Alcohol x [1-(Baume x 0.015)]