Page 26 - GrapevineMarApr 2022

In The Winery

alcohols. 15. Close the stopcock and repeat steps 3 through
14 above.
Procedure for Wine
16. From experience the operator will easily be able
1. We have calibrated the unit and have wines to run about 5 tests with these units before the
ready to test. cool water in the upper condenser needs to be
refreshed and the alcohol burner needs to be
2. Make sure the upper condenser is filled with filled with ethyl alcohol. (Be careful as alcohol
cool water. is flammable).

3. Fill the glass cylinder supplied to the line “vin” Calculation
(roughly 50 milliliters) with the wine you plan to
test. As you can see there is no real calculation here.
Just using the slide rule circular chart and making
4. Place this amount of wine in the boiling cham- sure to use a steady hand while making future
ber once again through the thermometer ori- readings. Make sure not to accidently move the
fice. inside circle on the “slide rule” as readings will be
affected. If this does happen you will need to relo-
5. Replace the thermometer in that orifice imme- cate the chart to the recorded distilled water boil-
diately. ing point or actually re-establish that data point via
the steps under calibration above.
6. Light and place the burner under the chimney
to heat the wine sample.
Other Helpful Tips
7. Wait about 3 to 5 minutes to hear the similar
rumble in the unit as noted previously above in Residual sugar : The boiling point of a wine is
step 5 under the distilled water calibration sec- raised if the wine has a perceivable residual sugar.
tion. The raising of the boiling point temperature gives a
false low alcohol reading for the wine. A wine high-
8. Watch the mercury rise and wait patiently for it er in alcohol will boil at a lower temperature due to
to steady on a reading. It will be jumpy at first the fact alcohol has a low boiling point. Sugar will
but allow it to remain on one reading, steady, interfere with the readings
for about 30 seconds.
Reproducible results : If this is your first time using
9. Record that boiling point. one of these units be sure to run several tests on
the same wine to make sure you can achieve sim-
10. Remove the burner and blow it out. ilar results with each test. If you can’t achieve the
same results dig deeper to look for errors.
11. Carefully look on the calibration circular slide
rule for that temperature reading. Spot check your results from time to time with a
competent outside lab to see if results are within
12. Follow the chart carefully to see what alcohol ranges expected. If not – look for sources of error.
level that reflects.
While performing the test make sure to calibrate
13. Record that alcohol reading in the proper places the unit with distilled water if you notice atmo-
for your records. spheric changes taking place outside. At a min-
imum it may be best to calibrate the unit every
14. Carefully dump the boiled wine sample in a lab three hours or so. Recall to flush the chamber out
sink or other container. Recall this is very hot with upcoming wine sample after calibrating with
and know that you may need to gently tilt the distilled water to avoid false / water diluted read-
unit toward the stopcock opening to get the ings.
entire sample out.
Typically these units are very foolproof and last for

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