The Australian Wine Research Institute, P.O. Box 197, Glen Osmond, SA 5064, Australia.
Molecules. 2022 Mar 22;27(7):2046. doi: 10.3390/molecules27072046.
The winemaking by-product grape marc (syn. pomace) contains significant quantities of latent flavour in the form of flavour precursors which can be extracted and used to modulate the volatile composition of wine via chemical hydrolysis. Varietal differences in grapes are widely known with respect to their monoterpene content, and this work aimed to extend this knowledge into differences due to cultivar in volatiles derived from marc precursors following wine-like storage conditions. Marc extracts were produced from floral and non-floral grape lots on a laboratory-scale and from Muscat Gordo Blanco marc on a winery -scale, added to a base white wine for storage over five to six months, before being assessed using a newly developed membrane-assisted solvent extraction gas chromatography-mass spectrometry (GC-MS) method. The geraniol glucoside content of the marc extracts was higher than that of juices produced from each grape lot. In all wines with added marc extract from a floral variety, geraniol glucoside concentration increased by around 150-200%, with increases also observed for non-floral varieties. The relative volatile profile from extracts of the floral varieties was similar but had varied absolute concentrations. In summary, while varietally pure extracts would provide the greatest control over flavour outcomes when used in winemaking, aggregated marc parcels from floral cultivars may provide a mechanism to simplify the production logistics of latent flavour extracts for use in the wine sector.
酿酒副产物葡萄渣（同义词为葡萄皮渣）中含有大量以风味前体形式存在的潜在风味物质，可以通过化学水解提取并用于调节葡萄酒的挥发性成分。葡萄品种之间的单萜烯含量差异是众所周知的，本研究旨在将这一知识扩展到由于品种差异导致的在葡萄酒储存条件下，来自葡萄皮渣前体的挥发性物质的差异。在实验室规模上，从花香和非花香葡萄批次以及麝香葡萄皮渣中提取葡萄渣提取物，并在酿酒厂规模上从麝香葡萄皮渣中提取，添加到基础白葡萄酒中储存五个月至六个月，然后使用新开发的膜辅助溶剂萃取气相色谱-质谱联用（GC-MS）方法进行评估。葡萄渣提取物中的香叶醇葡萄糖苷含量高于每个葡萄批次生产的果汁。在添加了花香品种的葡萄渣提取物的所有葡萄酒中，香叶醇葡萄糖苷的浓度增加了约 150-200%，非花香品种也观察到了增加。花香品种提取物的相对挥发性图谱相似，但绝对浓度不同。总之，虽然纯品种提取物在酿酒中使用时可以更好地控制风味效果，但来自花香品种的葡萄渣综合批次可能为简化潜在风味提取物在葡萄酒行业中的生产物流提供了一种机制。
