A recent economic analysis has estimated the New York wine and grape industries contribute $6 billion per year to the state economy, with much of the recent growth occurring in the premium winegrape and wine sectors. Further improvements in New York State wine will demand a better understanding of how vineyard practices influence wine flavor. Consistent production of premium wines is challenging in our cooler climate, and red wines can have excessive herbaceous and unripe flavors, particularly in poor growing years. Determining the compounds responsible for unripe flavors and understanding how these compounds are affected in the vineyard and the winery will be essential for sustained industry growth.

Consistent production of premium wines in cool climates like New York State is challenging. For example, in poor years, wines may have excessive herbaceous and unripe flavors. Additionally, the flavor chemistry of several popular cool-climate grape varieties is not well-studied, which makes recommendation for improving quality difficult. Understanding how the flavor of New York wines develops from vine to bottle is essential for raising the per-bottle price of wine and eventually for improving returns to both grower and winemaker.

The collaborative team of Gavin Sacks (Dept of Food Science and Technology), Justine Vanden Heuvel (Dept. of Horticultural Sciences and Dept. of Horticulture) and Alan Lakso (Dept. of Horticultural Sciences) has investigated the impact of vineyard conditions on the "methoxypyrazines" (MPs). The MPs are a potent class of flavor compounds with green pepper and vegetal aromas found in several popular red varieties, including Cabernet Sauvignon, Cabernet Franc, and Merlot. We have discovered that increasing exposure of clusters to light and reducing vine growth appear to reduce the accumulation of MPs early in the growing season, but that these factors are less critical late in the season. Controlling MP levels in harvested grapes thus demands early intervention. Dr. Sacks’ group has also investigated the use of novel materials for removing MPs from juice prior to fermentation on a micro- and small scale. Finally, Dr. Sacks is identifying other flavor compounds that may reinforce or mitigate the perception of unripe flavors in red wines.

Preliminary results on the effects of vineyard practices on the vegetal-smelling MPs will be presented to grapegrowers and winemakers at industry workshops in 2008, including the New York State Wine Industry Workshop. Recommendations on how to modify existing practices based on our preliminary results will also be presented. We expect our recommendations to result in fewer wines with excessive “weedy” and “green” characters. Often, these wines must be blended and/or sold at a lower price point to maintain the reputation of the winery. Prices per bottle varietal wines made from premium red winegrapes grown in New York State (Cabernet Franc, Cabernet Sauvignon, Merlot) can range from $10 to over $100. Small improvements in the consistency of red wine production can translate into improved profitability for both growers and winemakers.