OVERVIEW
The objective of this project is to quantify the return on investment (ROI) of conventional vineyard management strategies thought to improve the overall quality and character of both wine grapes and finished wine. This project leverages the VI grape ripeness project by extending analyses to human sensory evaluation in order to link chemical signatures to consumer appreciable markers of quality. By testing the degree to which potentially costly field manipulations yield consumer perceptible improvements we will identify the vinicultural strategy(ies) that maximize quality and profit of BC white wines. This project represents the first of its kind for British Columbia in that state-of-the-science technical analyses are ground checked against real world market valuation in determining which results deliver consumer-relevant improvements (willingness to pay) to the character and quality of wine.

OBJECTIVES
We will directly assess ROI of the three most common, yet largely untested viticulture strategies in BC, all assumed by growers to improve fruit (and thus wine) quality. Leaf removal (LR), kaolin clay application (KC) and cluster thinning (CT), the practice of intentionally reducing fruit yield in hopes of improving the quality of remaining fruit. The VI Grape Ripeness Project is providing important insight into the effect of LR and KC on the diversity and abundance of flavour-producing compounds at a molecular level. Here we add CT to the technical analyses and then process all grapes subjected to the LR, KC and CT treatments through to finished wines where each will be subjected to rigorous human sensory analyses. The logic here is that preliminary molecular analyses are already showing significant responses to field manipulations. However, to what extent these differences translate to consumer-perceptible changes in the bottle must be quantified before the true value of these costly field manipulations can be known. In so doing we complete the loop between technical science and the consumer, between chemical signatures of quality and consumer perceived quality. This information will be used to inform growers and producers on what manipulations represent viable strategies to improve quality and potential profits.

METHOD
To determine the characteristic aroma and flavour profiles of 8 experimental wines, and the overall consumer preference for each wine. The wines being assessing are produced from Pinot Gris grapes grown at 2 separately owned commercial Cowichan Valley vineyards, subjected to 1 of 4 vineyard treatments, and harvested in 2019. Participants in this study will help us assess the Return on Investment (ROI) for various vineyard management strategies aimed at improving the overall quality of wine grapes and wine produced on Vancouver Island.

There will be 2 types of consumer analysis completed;
1) trained panel of judges to create detailed flavour and aroma profiles for the experimental wines permitting specific flavours / aromas of each wines to be identified together with the relative intensity of each
2) consumer evaluations will involve volunteers from the general public. This stage of the experiment will use the same 8 wines but focus only on consumer preference for each wine. Volunteers will be asked their “willingness-to-pay" for a wine, after they have tasted each wine. These data will help us understand the ROI that wine producers may expect, should they choose to adopt the specific vineyard management strategy associated with that wine.

Our 4 treatments are:

(1) Control  (following vineyard SOPs)
(2) Heavy Leaf Removal with Kaolin Clay (removing all leaves surrounding clusters combined with a natural kaolin 'sunscreen')
(3) Cluster Thinning (intentionally removing a subset of grape clusters)
(4) Combination: Leaf Removal with Kaolin + Cluster Thinning

These treatments are intended to increase the overall ripeness and heighten the flavour/aroma complexity of the grapes to make better wine, while limiting the cost to grape growers and wine producers.
This research is being completed in conjunction with an ongoing research project that is currently analyzing the molecular chemical profile of these grapes. The data from that project will ultimately be combined with data from this project to better understand how grape ripeness and flavour/aroma translates from a technical analysis to the consumer. By doing so we will not only be trying to improve wine on Vancouver Island, but assessing the efficacy of current research standard for wine analysis (Gas Chromatography Mass Spectroscopy [GC-MS]).

The questions we seek to answer are as follows:
1) Do our vineyard treatments (2, 3, or 4) significantly change the the flavour and/or aroma profile of Pinot Gris wine compared to the control (1)?
2) Are consumers willing to pay more for any of the experimental wines (2, 3, or 4) compared to our control (1)?
3) Do the perceived benefits (increased willingness to pay) outweigh the increased costs associated with our treatments?

Identification of specific aroma chemicals affecting (+/-) perceived quality and thus providing the necessary baseline references for future harvests to amplify “+ve” elements while diminishing the “-ve” ones; this being the first step in establishing a unique BC terroir in much the same fashion that New Zealand won over the world by developing techniques to increase methoxypyrazine (“gooseberry”) in its Sauvignon Blanc wines.