Cabernet Franc is being grown in the Hudson Valley by the major producers in this region including Tabour and Millbrook Winery in Dutchess County, Glorie, Whitecliff and Brotherhood Wineries in Ulster County, Warwick Valley and Benmarl Winery in Orange counties. This variety has been favorable choice for cool climate growing regions among Vitis Vinifera varieties because is cold hardy and produces well-balanced, structured wine. However, increased accumulation of methoxypyrazines (MPs) in the fruit has been broadly reported and related to cool climate. This compound has been regarded as having a negative impact on wine quality and described as “green pepper” or “vegetal” aroma. Therefore, finding a successful, time efficient and economical approach for controlling the MPs accumulation in Cabernet Franc fruit is crucial for producing the highest quality wine.
Currently available literature agrees that enological methods for removing MPs during wine fermentation or after had limited success primarily because they could not selectively target MPs without interfering with and reducing desirable compounds of the wine as well. On the other hand, viticultural methods and vineyard management have shown potential to control MPs by manipulating the factors that have direct impact on MPs accumulation or its degradation. Previous research showed that early cluster exposure to light and crop load had significant influence on MPs reduction. However, it is less known which methods has better control over MPs accumulation and at the same time is more time efficient and economically sound. Manual leaf pulling cost rates from $130.00 to $270.00 per acre, depending on the growing area and planting density. Our research evaluates effect of leaf pulling on the quality of locally produced Cabernet Franc grapes while at the same time comparing it to the techniques used to obtain vine balance, such as balanced pruning and crop thinning.
The research has been conducted in Whitecliff vineyard & winery in Gardiner, Glorie Winery in Marlboro, and Millbrook Winery in Millbrook, NY and supported by the New York Wine and Grape Foundation for 2017 and 2018.