Riesling wines

Baderschneider, B. and Winterhalter, P., Isolation and characterization of novel benzoates, cinna-mates, flavonoids, and lignans from riesling wine and screening for antioxidant activity. J. Agric. Food Chem. 49, 2788, 2001. 

Flg.11.3 Impact of must concentration technologies on aroma compounds in Riesling wines ( =3) [94]... 

Riesling wine rignin new shikimic acid metabolite [104]... 

As a consequence of bottle aging, carbohydrate conversions can occur, although slowly at cellar temperature, to form the caramel-like 2-furfural aroma for example, in aged Madeira wines. Rapp and Giintert (86MI141) have shown that such carbohydrate decomposition in Riesling wines leads to 2-furfural 9,2-acetylfuran 10, ethyl furan-2-carboxylate 11, 2-formyl pyrrole 12, and 5-hydroxymethylfurfural 13. 

Additional oxygen heterocycles with a furan ring are lignans 56 and neolignans 57, which have been isolated from Riesling wine (01JAFC2788) ... 

The remnants of a very old, dry-farmed V. vinifera vineyard near Union Gap, in the Yakima Valley, still exist. It is reported to have been planted in the 1880s. The first documented planting of V. vinifera grapes in the Yakima Valley were planted in 1930 by W. P. Bridgeman. The first V. vinifera wines produced were made by Mr. Bridgeman at the Upland Winery in Sunnyside in 1936. A White Riesling wine was produced for several years before being discontinued. 

Winterhalter, R, Sefton, M.A., Williams, P.J.. (1990). Two-dimensional GC-DCCC analysis of the glycoconjugates of monoterpenes, norisoprenoids, and shikimate-derived metabolites form Riesling wine. 7. Agric. Food Chem., 38, 1041-1048. 

Bonnlander, B., Baderschneider, B., Monika Messerer, M., Winterhalter, P. (1998). Isolation of Two Novel Terpenoid Glucose Esters from Riesling Wine. J. Agric. Eood Chem., 46, 1474-1478. 

Winterhalter, R. (1993). The generation of Ci3-norisoprenoid volatiles in Riesling wine. In J. Crouzet, C. Elanzy, C. Martin, J.C. Sapis (Eds.), Connaissance aromatique des cepages et qualite des vins (pp.65-73). Montpellier Revue frangaise d oenologie. 

Gawel, R., Van Sluyter, S., Waters, E. J. (2007b) Xhe effects of ethanol and glycerol on the body and other sensory characteristics of Riesling wines. Australian Journal of Grape and Wine Research, 13, 38-45. 

Komes, D., Ulrich, D., and Lovric, T. (2006). Characterization of odor-active compounds in Croatian Rhine Riesling wine, subregion Zagoije. Eur. Food Res. TechnoL, 222, 1-7. 

Among the derivates of HBAs, further compounds have been identified. GUntert et al. (1986) identified ethyl esters of vanillic acid and p-hydroxybenzoic acid, and methyl esters of vanillic acid and protocatechuic acid. Ethyl esters of protocatechuic acid and vanillic acid, as well as the glucose ester of vanillic acid, were isolated from a German Riesling wine (Baderschneider and Winterhalter 2001). Analytically, HBA are mostly determined as trimethylsilane derivatives by using... 

Fig. 9C.8 Structures of lignans and neolignans isolated from a German Riesling wine...

Herrick, I. W., Nagel, C. W. (1985). The caffeoyl tartrate content of white Riesling wines from Cafifomia, Washington, and Alsace. Am. J. Enol. Vitic., 36, 95-97. 

Analysis, Structure, and Reactivity of Labile Terpenoid Aroma Precursors in Riesling Wine... 

The role of these glycoconjugates in the formation of important wine aroma volatiles is discussed. In addition, the identification of uncommon glycoconjugates in Riesling wine is reported. These novel wine constituents include 2-phenylethyl-a-D-glucopyranoside, the N-glucoside of 2-ethyl-3-methylmaleimide as well as the Ji-D-glucose ester of 10,11-di-hydroxy-3,7,1 l-trimethyl-2,6-dodecadienoic acid. 

Figure 3. Structures of two newly isolated glycoconjugates from Riesling wine.

Figure 4. Structure of the newly identified glucose ester 9 from Riesling wine.

Whereas the glucose ester 9 has been identified for the first time as a natural wine constituent, glycoconjugates of its reduced form, i.e. of the monoterpene diol 11, are known Riesling wine constituents (2). Under acidic conditions, diol 11 was partially converted into the bicyclic ether 12, the so-called dillether (2). In analogy to the formation of ether 12 from terpene diol 11, a likely formation of lactone 10 from acid 9A could be be expected (cf. Fig. 5). This so-called wine-lactone 10, first identified as an essential oil metabolite in the Koala (55), has recently been established by Guth (34) as a major aroma contributor in two white wine varieties. The 35,3a5,7aR-configured isomer of 10, which has been identified in wine, is reported to possess an unusual low flavor threshold of 0.01-0.04 pg/L of air and a sweet, coconut-like aroma (55). 

Isolation of Two Glucosidic Precursors of B-Damascenone From Riesling Wine. 

Figure 7. Structures of two acetylenic precursors of B-damascenone 19 isolated from Riesling wine.

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