Measure Ethanol up to 3%

The Ethanol Sensor measures the concentration of gaseous ethanol, from which the concentration of ethanol in a solution may be inferred. The sensor’s probe contains a material whose resistance decreases in the presence of ethanol. The sensor translates this resistance into an ethanol concentration measurement, which is recorded and displayed by the connected computer or datalogger. The Ethanol Sensor is well-suited for continuous recording and discrete measurements.

• The PASPORT Ethanol Sensor can be used with the EcoChamber (ME-6667) to perform yeast fermentation experiments.  See the full solution.

Other factors that affect measurement

• The ethanol sensor has a temperature dependent response. See the instruction manual for response curve against temperature.
• Air flow around or into the probe affects its temperature. Minimize airflow during calibration and measurement.
• In addition to ethanol gas, the sensor responds to hydrogen, isobutane, carbon monoxide, and methane.

Monitor yeast-based production of ethanol

Monitor yeast activity based on ethanol production at different temperatures, with different concentrations of sugar, or with different types of sugars.

Precautions

Do not expose the probe to a gas containing more than 3% ethanol, including the gas above alcoholic beverages. Higher ethanol concentrations will deplete the sensing element. Note that the gas above a liquid contains about the same concentration of ethanol as the liquid itself.

Ensure that the membrane is installed and intact before immersing the end of the probe. The membrane prevents the sensing element from getting wet. If the sensing element accidentally gets wet, rinse and dry it quickly. Note that the probe may be degraded or destroyed if the membrane is ruptured or compromised.

Do not immerse the probe. The membrane (if it is in good
condition) will protect the probe in case of accidental immersion.
However, the probe is designed for use in gas only.

Calibration Technique (see instruction manual)

For accurate measurements, first calibrate the sensor. You will need a solution of 1% ethanol in water. The solution should be at the same temperature as the solutions to be measured.

Calibration data is stored in the sensor’s memory and it persists until the sensor is calibrated again, even if the sensor is unplugged from the interface.

1. Connect the sensor to an interface as described above.
2. Place the probe above the 1% ethanol solution (depending on how it will be used for later measurements).
3. Observe the ethanol concentration reading in software or on the datalogger.
4. Wait until the reading stabilizes.
5. Press and hold the 1% CAL button on the sensor for 4 s.

Immediately after a successful calibration, the sensor’s output reads 1%, and the button is illuminated.