Open Collections

Greene, Alisha Lasko

University of British Columbia

The wine industry in British Columbia is an important sector, generating approximately $3.75 billion annually to the provincial economy and contributing over $440 million in tax revenues. Unfortunately, the industry is challenged by the effects of climate change, such as wildfires. It is accepted that compounds present in wildfire smoke can affect wine grapes and the resulting wine. Artemisia tridentata Nutt. is an indigenous plant that often grows near vineyards in the South Okanagan wine growing region. I hypothesized that volatile compounds from growing and burning A. tridentata accumulated in commercial grapevines (Vitis vinifera L.) and that wildfire smoke influenced the terroir of finished wines. To investigate this hypothesis, my specific objectives were: (a) to develop and validate a method for detection and quantification of terpenes in Vitis vinifera L. grapevine leaves and wine; (b) to determine Artemisia tridentata derived terpenes in Vitis vinifera leaves after different passive and extracted exposures to Artemisia tridentata; and (c) to characterize smoky wine and award-winning wines from the South Okanagan wine growing region using metabolomics. My data show that terpenes released in burning A. tridentata accumulated in Vitis vinifera leaves. Both terpenes detected in the A. tridentata extracts and their degradation products were also detected in the treated leaves. After a metabolomic investigation of very smoky wine and unaffected wine produced by the same winery a year later, two hypotheses were generated: 1) wildfire stresses and smoke exposure increase the accumulation of nitrogen through the arginine and proline pathways, potentially resulting in unpalatable flavour metabolites such as ornithine, putrescine, and others; and 2) wildfire and smoke exposure alter the biosynthesis of tannins and the metabolism of quercetins during grape development thereby altering the character of wines. Together, these data improve our understanding of smoke events on grapevine chemistry and terroir.

Text

2024-08-09

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/88918

Chemistry

University of British Columbia

UBCO

http://creativecommons.org/licenses/by-nc-nd/4.0/