Project Number: 5358-21000-034-26
Project Type: Grant

Start Date: Sep 21, 2007
End Date: Sep 30, 2009

Objective:
1. Investigate the feasibility to use aroma and aroma precursor analysis in grapes as an additional measurement for grape quality evaluation. 2. Determine the impact of deficient irrigation on key aroma and aroma precursor development in Merlot grapes and the impact on wine aroma quality. 3. Determine the impact of kaolin-based reflectant on key aroma and aroma precursor development in deficit irrigated Merlot grapes and the impact on wine aroma quality.

Approach:
The trial at Skyline has 16 plots with each plot containing four rows of 14 vines per row. Vines were provided weekly with 35, 70, or 100% of estimated crop evapotranspiration. At each location, a kaolin-based particle film will be applied at a standard rate three times. Harvested grapes from 8 field treatments (4 irrigation levels, each with or without Kaolin) will be frozen and sent to the flavor chemistry lab for grape aroma and aroma precursor analysis. A newly developed stir bar sorptive extraction gas chromatography-mass spectrometry method will be used to analyze both free aroma as well as the glycoside bound aroma precursors. About 30 key aroma compounds will be selected based on their importance to Merlot wine aroma. Their concentrations in grape (both free and bound form) and the finished wine will be determined. Documents Grant with Oregon State University