1. What’s in your Vodka?
Alexandrea Miller, Aaron Kishlock and Dr. McElroy
Department of Chemistry, Indiana University of Pennsylvania, Indiana PA 15701
Abstract
This is a collaborative project with Disobedient Spirits in
Homer City, PA. We conducted chemical analyses of aqueous
and organic compounds analyzed at various stages of spirits
production.
Results from the analyses will assist the distillery to improve
and stream line their operations and ultimately lead to a better
product.
Introduction
Disobedient Spirits contacted us to help them determine
where in the distilling process organic and inorganic impurities
are coming into their products and how they can reduce these
concentrations. These impurities are a problem because they
affect the taste of their products.
Inductively Coupled Plasma Optical
Emission Spectrometry (ICP-OES)
This is an emission spectroscopy test that is used to find trace metals in a
liquid sample. Using inductively coupled plasma, atoms and ions are excited
that then produce an electromagnetic radiation which is unique for each
element. The concentration for the electromagnetic radiation is based on the
intensity of the emission that is produced.
What is next
The initial goal of this experiment was to help Disobedient Spirits to
improve on their alcohol and to have a way to measure the organic compounds
found in their products. This is the ground work for the future experiments to
come that will help us to develop a protocol to use to more efficiently find the
various compounds in the samples.
The GC-MS is an ongoing process and will be continued throughout the
semester. In the next experiments to come, we plan to try different solvents to
elute the samples with after running the Sep-pak.
References
Robinson, J., Skelly Frame, E., & Frame II, G. (2005). Atomic Emission
Spectroscopy. In Undergraduate Instrumental Analysis (6th ed., pp. 483-497).
New York, New York: CRC Press.
Robinson, J., Skelly Frame, E., & Frame II, G. (2005). Mass Spectrometry 1:
Principles and Instrumentation. In Undergraduate Instrumental Analysis (6th
ed., pp. 613-619). New York, New York: CRC Press.
Robinson, J., Skelly Frame, E., & Frame II, G. (2005). Chromatography with
Liquid Mobile Phases. In Undergraduate Instrumental Analysis (6th ed., pp. 839-
843). New York, New York: CRC Press.
Ackland, T. (2015, January 20). Home Distillation of Alcohol (Homemade Alcohol
to Drink). Retrieved April 2, 2015, from
http://homedistiller.org/intro/methanol/methanol
Distillation of Alcohol. (n.d.). Retrieved April 2, 2015, from
http://infohost.nmt.edu/~jaltig/Distillation.pdf
Ion Chromatograph (IC)
This is a chromatographic separation method for charged particles
(anions or cations) to be separated and quantified from an aqueous sample.
In this study, negatively charged ions (anions) were analyzed using a
NaCO3/NaHCO3 (sodium carbonate/sodium bicarbonate) mobile phase and
suppressed anion system, with detection by a conductivity detector.
Contents Notes
Distilled Water -RO H20 Control
Cherry Whiskey All steps of distilling completed. This
was distilled and then aged in oak
barrels with cherries.
Gin Gin post distilled
3rd Distilled Vodka This vodka has gone through 3
distillations.
4th Distilled Vodka This vodka has gone through 4
distillations.
5th Distilled Vodka This vodka has gone through 5
distillations.
6th Distilled Vodka This vodka has gone through 6
distillations.
Metal Parts Per Million
Calcium 0.62 ppm
Magnesium 0.28 ppm
Iron 0.07 ppm
Manganese 0.09 ppm
Aluminum 0.49 ppm
Strontium 0.01 ppm
Gas Chromatography–Mass Spectrometry
(GC-MS)
This is a technique that is used to separate gas phase ionized atoms to find
the mass-to-charge ratio to help determine what the substance in the sample is.
Ions are separated based on their mass-to-charge ratio and then the
concentration of those ions is measured. This analysis helps to determine the
substances in the sample by providing the mass of the molecules and the
molecular structure of inorganic and organic compounds found.
During our testing, we ran into a few minor problems. For one, we were
not able to directly inject the alcohol samples straight onto the GC-MS because
the water in the alcohol sample would have damaged the column in the GC-MS.
Because of this, we filtered the sample using reverse phase C-18 Sep Pak. This
helped to get rid of the water that was in the sample.
First we used acetonitrile, an organic solvent, to prep the Sep-pak column
for the samples. Then the samples were loaded onto the Sep-pak. Lastly, hexane
was used to elute the sample. This was chosen because it is very non-polar and
is a good solvent for diluting and injecting into the GC. .
Fermentation
The fermentation process begins with mixing a source of
sugar, water and yeast. Then typically, the yeast is put in an
oxygen free environment. The anaerobic environment forces the
yeast to stop using the sugar as a food source and makes the
yeast ferment alcohol instead.
With regards to alcohol, the wort is highly oxygenated
before the yeast is introduced. This helps to speed up the
process to produce the alcohol.
Samples Collected