2019 Jogue Scholarship - Zhuzhu Wang

2019 Jogue Scholarship – Zhuzhu Wang

Bio:

Zhuzhu has a Bachelor’s in chemistry, and Masters’ degrees in Molecular Chemistry and Pharmaceutical Science.  Prior to admission to the PhD, she worked for over two years as a Research Scientist for Archer Daniel Midland (ADM) company. Currently, she is conducting her doctoral research in Flavor Science under the supervision of Dr. Keith Cadwallader at the University of Illinois at Urbana-Champaign. Zhuzhu’s research focuses on the effect of ethanol on the flavor perception of distilled spirits.

 

Research outline:

Despite the variety of classes and types, many people enjoy drinking distilled spirits on the rocks or with a splash water to open up the flavors. From a physicochemical perspective, the addition of water (dilution of ethanol) affects the spirit’s matrix in several ways. These include a decrease in surface tension, a change in the structure of the liquid water/ethanol matrix and a change in volatile compound partitioning/release from the bulk solution. However, physicochemical properties of the aroma compounds and ethanol only determine the likelihood that the aroma compounds will be released from the matrix into the headspace. Additional attention has also been drawn to the physiological impact of low ethanol content (caused by dilution with water) on aroma perception, as it partially reduces the pungency associated with high ethanol content, and more importantly, it increases olfactory sensitivity to the aroma compounds. In order to provide a clearer picture as to the physiological effects of ethanol on individual aroma compound perception, a modified gas chromatography-olfactometry (GC-O) system was built so that panel was able to sniff the GC effluent in a background of constant ethanol vapor of differing concentrations (generated from 0% ABV, 20% ABV, and 40% ABV solutions). In this way, the solvating effect of ethanol (such as in the case of distilled spirits) was totally excluded, so that any experienced alteration of aroma detection could be attributed solely to the physiological effect of ethanol from the vapor background. Our results support the physiological suppression effects of ethanol on aroma compound detection thresholds in air, suggesting a possible relationship between aroma compound structure and the degree of ethanol aroma suppression. Accordingly, this research will provide additional insights into the structure-function understanding at the molecular level in an effort to better explain the physiological suppression effect of ethanol on flavor perception.