Dr. Mary G. Chisholm

Professor Emerita of Chemistry

B.Sc.,1962, London University, United Kingdom.
Ph.D.,1966, Organic Chemistry, London University, United Kingdom.

Phone: (814) 898-6412
email: mac8@psu.edu


Behrend College Council of Fellows Excellence in Teaching award: 1974
American Chemical Society, Erie Section: Outstanding Member Award, 1995
Behrend College Council of Fellows Research Award: 1998
Sigma Xi Faculty Research Award: 2002


Visiting Scientist, Department of Food Science, New York State Agricultural Experiment Station, Cornell University. 1987-8
Visiting Scientist, Reading Scientific Services, Ltd., Cadbury Schweppes, Reading, UK. 1995-6.

Teaching Interests:

Organic Chemistry
Instrumental Analysis and its application to organic analysis
The applications of spectroscopy to the structure determination of organic compounds
I believe that chemistry is primarily an experimental science and I encourage my students to learn by experimentation. I encourage them to learn from both their success and mistakes and to benefit from our small classes where they can take advantage of the opportunities available to them to use modern instrumentation. I also believe that an active research program is the most powerful teaching tool available to show students the exhilaration of discovery and to teach them creative and independent thinking.

The instrumental analysis component of our chemistry major has been revised in response to the American Chemical Society's recommendations. This will give us an opportunity to update and streamline our use of instruments in the undergraduate curriculum.

Research Abstract:

My research is in the field of flavour chemistry, which is a part of an interdisciplinary field of study which is attempting to unravel the mechanism of olfaction. I am studying the aroma characteristics and flavour quality of Lake Erie regional wines in collaboration with Presque Isle Wine Cellars of North East, Pa. This work has included identifying the characteristic aroma compounds of French American hybrid white wines, andexamining some flawed wines by measuring the odour activity of compounds formed during spoilage.  Recently I began to work with citrus oils as a result of my sabbatical in 1995-6. Very little is published about the aroma volatiles of lime oil and I am anxious to examine the role of chirality in the aroma composition of Key lime oil. We hope to discover more about aroma interactions using lime oil as a model.

My work uses an aroma bioassay, which uses a technique based on gas chromatography-olfactometry, known as CharmAnalysis. The aroma data from a set of serial dilutions of an extract are sorted by the computer to produce an aroma or Charm chromatogram which provides a measure of the odour intensities of the odour-active components of the sample. We have found some interesting discrepancies between sensory aroma data and GCO data, which suggests to us that we still have a poor understanding of the behaviour of mixtures of aroma compounds when they reach the nose.

We have been funded by the National Science Foundation to look at human responses to simple mixtures of aroma compounds, using both sensory and GCO methods to collect the data, and to study the effects of chirality on lime oil aroma.

Student Research:

Students who choose to join our group will learn some fundamental techniques common to many areas of chemistry: High resolution gas chromatography, and trouble shooting of a modern gas chromatograph.
Gas chromatography-olfactometry, using an aroma bioassay called CharmAnalysis.
Gas chromatography-mass spectrometry for the identification of aroma compounds, often at trace levels
The use of SPME and preparative chromatography to concentrate samples for better identification of aroma compounds.
Simple extraction and sample preparation.
The opportunity to present their research at a national conference.


Improvement of a Research Program in Flavour Chemistry by the Addition of Chiral Gas Chromatography. National Science Foundation-CAA. $52,774. 1995-98.

Integration of gas chromatography-mass spectrometry throughout the curriculum in a new major. National Science Foundation-ILI. $33,704. 1996-98 (with Timothy Friebe).

Introductory Polymer Chemistry for Plastics Technology Students. Curriculum Development Award sponsored by the American Chemical Society, Division of Polymers and Polymeric Materials. $10,000, 1998-9.

Recent Publications:

Chisholm, M.G. and J.M Samuels*. Determination of the Impact of Metabolites of Sorbic Acid on the Odor of a Spoiled Wine.
J. Agric. Food Chem.1992, 40,630-633.

Chisholm, M.G., L.S. Guiher*, T.M.Vonah* and J.L.Beaumont*. Comparison of Some French-American Hybrid Wines with White Riesling using Gas Chromatography-Olfactometry. Amer. J. Enol. Vitic.1994, 45,201-212.

Chisholm, M.G., L.S. Guiher* and S.M. Zaczkiewicz*. Aroma Characteristics of Aged Vidal Blanc Wine. Amer. J. Enol. Vitic.1995, 46,56-62.

Chisholm, M.G., M.J. Palisin*, K.R. Stank* and J.L. Beaumont*. The Role of Gas Chromatography-Olfactometry in Assessing Wine Aroma. Proceedings of the 4th International Symposium of Cool Viticultural and Enology.VII, pp 27-32, 1996

Baigrie, B.D., M.G. Chisholm, and D.S. Mottram. The Effect of Processing on the Chiral Aroma Compounds in Fruits and Essential Oils. In: Flavour Science, Recent Developments. Royal Society of Chemistry, 1996; pp 151-157.

Chisholm, M.G. and P.E. Koch. An Introductory Polymer Chemistry Course for Plastics Technology Students. J. Chem. Educ.2000, 77, 1147-1151

Chisholm, M.G., M.A. Wilson*, G.M. Gaskey*, J.A. Jell* and D.M. Cass, Jr.*, The Identification of Aroma Compounds in Key Lime Oil Using Solid Phase Micro-extraction and Gas Chromatography-Olfactometry. In: Gas Chromatography-Olfactometry -The State of the Art.ACS Symposium Series 782, American Chemical Society, Washington, DC, 2001; pp 100-112.

Chisholm, M.G. Chiral Analysis. Stereodifferentiation of Chiral Odorants Using High Resolution Gas Chromatography. In: Current Protocols in Food Analytical Chemistry. R.E. Wrolstad et al. Eds. John Wiley & Sons, Inc., New York, 2001. pp G1.4.1- G1.4.20.

Chisholm, M.G., M.A. Wilson*, and G.M. Gaskey*,  Characterization of Aroma Volatiles in Key Lime Essential Oils (Citrus aurantifolia Swingle). Flavour & Fragr. J. 2003, 18, 106-115.

Chisholm, M.G., J.A. Jell*, and D.M.Cass, Jr.*,  Characterization of the Major Odorants Found in the Peel Oil of Citrus reticulata Blanco cv. Clementine, Using Gas Chromatography-Olfactometry. Flavour & Fragr.J.  2003, 18, 275-281.

* Student


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Interested persons may contact me for information at: mac8@psu.edu or (814) 898-6412

Last modified:  January 31st, 2005