Author ORCID Identifier
Year of Publication
Master of Science (MS)
Agriculture, Food and Environment
Plant and Soil Sciences
Dr. Seth DeBolt
Quercus alba has been the prominent tree species utilized in the spirits industry for decades. Of its many qualities, the ability to impart desirable flavors on spirits combined with its natural abundance makes it the ideal choice for barrels. Creating barrels is a uniform process, but variability still exists in aged spirits even when all other parameters are controlled. In this thesis, I explore how the origin of Quercus alba influences metabolite variability.
Quercus alba is a resilient species that can grow in many climates. This is seen through Quercus alba’s vast growing range, of which barrel quality white oak is harvested from. White oak contains compounds that are important to distillers, imparting flavors of smokiness, spice, sweetness, coconut, and nuttiness to name a few, to aged products. These metabolites of interest were quantified and compared between the ten regions sampled.
The three main cell wall components, cellulose, hemicellulose, and lignin were analyzed because of their breakdown components resulting from the cooperage process. Other metabolites were also quantified for their direct flavor contributions to aged products including phenolic compounds, hydrolyzable tannins, and four volatile compounds: cis-whiskey lactone, trans-whiskey lactone, eugenol, and vanillin.
Comparison between regions showed significant differences in eight of the nine metabolites. In addition, the coordinates obtained from sampling were used to investigate potential correlations between environmental trends and metabolites. Numerous factors were evaluated that can be categorized under the features soil, water, and elevation. Findings showed significant correlations with several combinations of metabolites and environmental variables. Utilizing the trends found in this work can lead to the development of a targeted approach for sampling white oak.
Digital Object Identifier (DOI)
Research funding was provided by Independent Stave Company and Makers Mark Distillery from 2019-2022 during the duration of the project.
Byrd, Zachary Alexander, "The Site Evaluation of Quercus alba Metabolites" (2022). Theses and Dissertations--Plant and Soil Sciences. 154.
Available for download on Friday, July 05, 2024