Dienstleistungszentrum Ländlicher Raum (DLR) Rheinpfalz, Institute for Viticulture and Oenology, Breitenweg 71, Neustadt an der Weinstraße 67435, Germany.
Department of Chemistry, Kaiserslautern University of Technology, Erwin-Schrödinger-Straße 52, Kaiserslautern 67663, Germany.
J Agric Food Chem. 2020 Mar 25;68(12):3834-3849. doi: 10.1021/acs.jafc.0c00049. Epub 2020 Mar 16.
The C-norisoprenoid aroma compounds 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) and biosynthetically related vitispirane (VS) are important contributors to the varietal aroma of Riesling wines and are released from glycosidically bound carotenoid breakdown products during bottle aging. TDN is appreciated by numerous winemakers, particularly in aged Riesling wines. Higher levels of TDN, however, are perceived as a "petrol" off-flavor, which is expected to increase due to ongoing climate change. Wines produced from the same Riesling clone, which was grafted on six different rootstocks, varied significantly throughout two vintages in respect to their concentrations of free and bound TDN and VS as well as other volatiles. Over three vintages, the same compounds differed significantly among wines made from eight Riesling clones grafted on the same rootstock. Genetically determined loose grape clusters favored the formation of TDN and yielded wines of stronger sensory petrol intensity. Berry size, however, had no relevant impact on TDN and VS formation.
C-降诺里西二烯醇类香气化合物 1,1,6-三甲基-1,2-二氢萘（TDN）和生物合成相关的牻牛儿醇（VS）是雷司令葡萄酒品种香气的重要贡献者，并且在瓶陈过程中从结合糖苷的类胡萝卜素分解产物中释放出来。TDN 受到众多酿酒师的赞赏，特别是在陈酿的雷司令葡萄酒中。然而，较高水平的 TDN 被认为是一种“汽油”异味，预计由于持续的气候变化，这种异味会增加。用同一雷司令克隆系种植在六种不同砧木上的葡萄酿造的葡萄酒，在两个年份中，其游离和结合 TDN 和 VS 以及其他挥发性物质的浓度差异显著。在三个年份中，用同一砧木嫁接的八个雷司令克隆系酿造的葡萄酒中，相同的化合物差异显著。由遗传决定的松散葡萄串有利于 TDN 的形成，并产生具有更强感官汽油强度的葡萄酒。然而，浆果大小对 TDN 和 VS 的形成没有影响。
