TY - JOUR T1 - Volatile Constituents of Grape Leaves. I. Vitis Vinifera Variety 'Chenin Blanc' JF - American Journal of Enology and Viticulture JO - Am J Enol Vitic. SP - 148 LP - 153 DO - 10.5344/ajev.1975.26.3.148 VL - 26 IS - 3 AU - H. L. Wildenradt AU - E. N. Christensen AU - B. Stackler AU - A. Caputi, Jr. AU - K. Slinkard AU - K. Scutt Y1 - 1975/01/01 UR - http://www.ajevonline.org/content/26/3/148.abstract N2 - 'Chenin blanc' grape leaf volatile compounds were isolated by steam distillation. The distillate collected was extracted with pentane, and the compounds present were identified by gas chromatography/mass spectrometry. Prominent in grape leaves are the six-carbon compounds: cis-2-hexenal, trans-2-hexen-1-ol cis-3-hexen-1-ol, n-hexanol, trans-2-hexenol-1-ol, and cis-or trans-hexa-2,4-dienal. Also prominent are the terpenes and their derivatives: myrcene, linalool, alpha-terpineol, isopulegone, citral, geraniol, and ionone. Also identified were the sulfurcontaining compounds tetrathiocane and cis- or trans-3,5-dimethyl-1,2,4,-trithiolane. Sensory evaluation of the compounds exiting from gas chromatographic columns indicated that the six-carbon compounds were largely responsible for the "grassy" flavor from the leaves.To confirm the influence of grape-leaf six-carbon compounds on wine grassy flavor, trans-2-hexenal, trans-2-hexenol, cis-3-hexenal, and n-hexenol in wine were evaluated by a taste panel. At 10 ppm or less, the compounds were detected at the 1% level of significance. To indicate whether six-carbon and other compounds might be released by macerated leaves in winemaking, wines were produced from grape juices containing 2% w/v leaves of which 0, 5, 15, and 25% w/w had been macerated. Taste-panel sensory evaluation of the wines indicated that 5% or more leaf maceration yielded wines of significantly lower quality. ER -