Title

An analysis of electrical conductivity and pH in acetous fermentation

Author(s)

Isabelle Doan

School Name

Southside High School

Grade Level

12th Grade

Presentation Topic

Chemistry

Presentation Type

Non-Mentored

Oral Presentation Award

3rd Place

Abstract

The measurement of electrical conductivity, a solution’s ability to conduct an electric current, is becoming widely used in ethanol and lactic acid fermentation, as an indirect way of testing the parameters of fermentation. In this work, we analyze how the measure of electrical conductivity can be used in acetous fermentation. Acetous fermentation is the oxidation of ethanol to acetic acid, typically by Acetobacter. During this process, the molecules of the solution tend to dissociate, allowing for greater electrical conductivity. We demonstrate the relationship between electrical conductivity and the fermentation of ethanol at different concentrations. Acetobacter cultures were placed in three different alcohols of varying ethanol content: red wine at 13.5% by volume, vodka at 40% by volume, and rum at 75.5% at volume, as well as a control group of water with no alcohol content. These samples were allowed to ferment for several weeks. Their conductivity was checked weekly, using a 90 conductivity probe. From the data, we found there was a steady increase in conductivity in all three alcohols. In addition, their pH was checked weekly using a pH probe.

Start Date

4-11-2015 11:45 AM

End Date

4-11-2015 12:00 PM

COinS
 
Apr 11th, 11:45 AM Apr 11th, 12:00 PM

An analysis of electrical conductivity and pH in acetous fermentation

The measurement of electrical conductivity, a solution’s ability to conduct an electric current, is becoming widely used in ethanol and lactic acid fermentation, as an indirect way of testing the parameters of fermentation. In this work, we analyze how the measure of electrical conductivity can be used in acetous fermentation. Acetous fermentation is the oxidation of ethanol to acetic acid, typically by Acetobacter. During this process, the molecules of the solution tend to dissociate, allowing for greater electrical conductivity. We demonstrate the relationship between electrical conductivity and the fermentation of ethanol at different concentrations. Acetobacter cultures were placed in three different alcohols of varying ethanol content: red wine at 13.5% by volume, vodka at 40% by volume, and rum at 75.5% at volume, as well as a control group of water with no alcohol content. These samples were allowed to ferment for several weeks. Their conductivity was checked weekly, using a 90 conductivity probe. From the data, we found there was a steady increase in conductivity in all three alcohols. In addition, their pH was checked weekly using a pH probe.