Resumen de Monoterpene levels in different grapevine (vitis vinifera l.) cultivars and clones during fruit ripening
M.J. Hey, M. Nitsch, E.H. Rühl
The objective of this study was to characterize and compare the monoterpene content and seasonal variation of different grape cultivars and clones. Grapes of aromatic, less aromatic, and non-aromatic cultivars were collected during ripening periods in 2007, 2008 and 2009 at the Geisenheim Research Center. Free and glycosid¬ically bound monoterpenes were extracted with a solid phase extraction-method (SPE) and analysed by GC/MS.
The focus was on the monoterpenols linalool, nerol, geraniol and terpineol; the furanoside and pyranoside cis/trans isomers of linalool oxide; and the aldehydes neral and geranial plus two diendiols. Results show large differences between cultivars and two clones of Traminer (Gewürztraminer). Highest contents were found in grapes like Siegerrebe and Muscat cultivars such as Morio Muskat. Only traces of monoterpenes were detected in Dornfelder and Chardonnay. During ripening, linalool increased significantly in most cultivars, while -terpineol levels varied only slightly with time.
