Vine performance, fruit composition, and wine sensory attributes of Gewurztraminer in response to vineyard location and canopy manipulation

An experiment was conducted on Gewurztraminer vines between 1988 and 1992 in the Okanagan Valley of British Columbia, Canada, to assess the impact of three canopy manipulation practices (unhedged control; hedged to ca. 14 leaves per shoot; basal leaf removal) at each of three vineyard sites [Oliver (Region II); Kaleden (Region I/II); Kelowna (Region I)]. The Kelowna site was characterized by lowest weight of cane prunings and canopy density, and highest cluster weight and number of berries per cluster. Site had no consistent effect on berry and juice degrees Brix, but highest pH, potassium (K+), free volatile terpenes (FVT) and potentially-volatile terpenes (PVT), and lowest titratable acidity (TA) were measured at the Oliver site. Basal leaf removal lowered degrees Brix, TA, pH, and K+, and increased FVT and PVT in the berries and juices in some years. In triangle tests, tasters could discern between some pairs of sites and canopy manipulation treatments on an aroma and retronasal aroma (hereinafter known as flavor) basis, and found in most cases that leaf removal wines had highest muscat and floral aromas and flavors. Descriptive analysis of wine sensory attributes showed that the Oliver site, and the hedging and leaf removal treatments, contained most intense fruity, muscat, and cedar aromas and flavors, as well as most body and aftertaste.