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WINEMAKING page 53), and that grape stems and grape leaves had even higher levels. To confirm that airborne transmission was responsible for the transfer of 1,8-cineole (from eucalyptus trees to the vines located close by) passive traps to capture the volatile aroma compound through adsorption onto polyethylene sheets were placed in the canopy at different locations at set distances from the eucalyptus trees. Again, the results confirmed previous findings: The closer the traps (and vines) were to eucalyptus trees, the higher the concentration of 1,8-cineole. Leaves from eucalyptus trees themselves also appeared to play a role. When the researchers collected clusters of grapes for the study, they often found eucalyptus leaves lodged in the canopy and within the grape bunches in vines closer to eucalyptus trees. The next step, therefore, was to quantify the effect on 1,8-cineole concentration if eucalyptus leaves found their way into ferments, in the form of MOG in the harvest bin. Five-hundred-and-fifty kilograms of Shiraz were picked by hand from the rows close to eucalyptus trees, taking special care to avoid MOG. The fruit was randomized and split into separate lots (50kg) for different treatments: one lot was pressed immediately (rosé style); a second lot contained crushed berries only with all grape stems and leaves thoroughly removed (no MOG); a third included grape leaves (500g) and stems (1.3kg) and the final batch included four eucalyptus leaves and a small piece of bark (total weight 3.5g). 1,8-Cineole concentrations were determined daily throughout fermentation. Again, the results were striking. While the inclusion of grape leaves and stems increased the concentration of 1,8-cineole, adding less than a handful of eucalyptus leaves had the most dramatic effect of all: It increased concentrations of the com- The presence of eucalyptus leaves—and to a lesser extent grapevine leaves and stems— were key drivers behind concentrations of 1,8-cineole in wine. pound from less than 2μg/L (for the control, i.e., no MOG) to above 30μg/L. Given the high number of eucalyptus trees in the Australian landscape and the fact that large amounts of eucalyptus leaves can be found naturally in grape bunches—the researchers found 33 eucalyptus leaves in just one 550kg lot of hand-picked fruit—the impact of eucalyptus leaves on wine character cannot be underestimated. Eucalyptus by design The results were clear: The presence of eucalyptus leaves—and to a lesser extent grapevine leaves and stems—were key drivers behind concentrations of 1,8-cineole in wine. While there were apparent differences between vintages, the proximity of eucalyptus trees had an obvious effect. The impact of MOG—and eucalyptus leaves in particular—was also very clear (see "Effect of Leaves and Stems on page 54). While not all eucalyptus species have high levels of 1,8-cineole in their leaves, many of Australia's winegrowing regions' common trees such as eucalyptus leucoxylon (Yellow Gum) The original, BOTTLE-MATIC-II 3 YEAR WARRANTY INCLUDED Front and Back! MADE IN USA! 21 day trial $1800 for Wines & Vines Readers! Front & Back! Label any cylindrical container fast and accurately from ½" to 8" diameter, @ Speeds of 1200 Pcs. per hour. NOT A CHEAP, IMPORTED KNOCK-OFF! ISPENSA-MATIC DLabel Dispensers STOP Wasting Time Labeling by Hand! Price subject to change without notice. 28220 Playmor Beach Rd, Rocky Mount, MO 65072 Call Toll Free: 1 (800) 325-7303 or (573) 392-7684 FAX:(573) 392-1757; E-mail: info@dispensamatic.com Web: http://www.bottle-labeler.com 2/01/10 Win es & Vin es F EB RUA RY 20 13 55