Botrytised wine
Botrytised wine is a category of wine produced from grapes affected by Botrytis cinerea under specific climatic conditions that promote so-called noble rot. Unlike destructive grey rot, noble rot partially dehydrates ripe grapes, concentrating sugars, acids and flavour compounds, and giving rise to some of the world’s most distinctive and long-lived sweet wines.[1]
Noble rot
[[Botrytis cinerea]] is a fungus that can infect grape berries in different ways depending on weather conditions. Noble rot develops when humid conditions encourage fungal growth followed by dry, sunny periods that halt its spread and allow gradual dehydration of the berries. The fungus perforates grape skins, leading to water loss and chemical transformations within the must.[2]
This process results in grapes with extremely high sugar concentration, modified acidity and altered aromatic precursors, forming the basis of botrytised wine styles.
Viticultural requirements
Successful production of botrytised wine depends on precise climatic balance. Regions suited to noble rot typically experience autumnal morning mists followed by warm afternoons, often near rivers or lakes that moderate humidity. Harvesting is labour-intensive, as grapes are usually picked in multiple passes to select only suitably botrytised berries.[3]
Because outcomes are highly vintage-dependent, botrytised wines are among the most variable and risky categories in viticulture.
Winemaking and composition
Musts from botrytised grapes ferment slowly due to high sugar levels and altered nitrogen composition. Wines typically retain significant residual sugar and show elevated glycerol, complex polysaccharides and distinctive aromatic compounds derived from fungal metabolism.[4]
These chemical characteristics contribute to the wines’ viscosity, sweetness and capacity for long ageing.
Styles and regions
Classic botrytised wines are produced in regions such as Sauternes and Barsac in Bordeaux, Tokaj in Hungary, and parts of the Loire Valley. Styles range from intensely sweet, richly textured wines to more delicately balanced expressions where acidity plays a defining role.[5]
Many appellations impose strict regulations governing minimum sugar levels, harvesting methods and labelling for botrytised wines.
Sensory characteristics
Botrytised wines are typically noted for aromas of honey, dried apricot, saffron, marmalade and exotic spice, alongside fresh acidity that prevents cloying sweetness. With age, flavours may evolve towards caramel, toasted nuts and complex oxidative notes while retaining structural balance.[6]
Historical significance
The use of noble rot in winemaking has been documented for several centuries, with some of the earliest recorded examples linked to [[Central Europe]]. Historical evidence suggests that botrytised wines were valued for both their sweetness and longevity well before modern microbiological understanding.[7]
Their rarity and production difficulty have long associated botrytised wines with prestige and high economic value.
Regulation
International definitions of wines produced with noble rot are recognised by organisations such as the OIV, which provides guidance on terminology and production practices to distinguish noble rot wines from those affected by spoilage.[8]
See also
References
- ↑ Robinson (ed.), The Oxford Companion to Wine, Oxford University Press, 2015, ISBN 978-0198705383.
- ↑ Jackson, Wine Science, Academic Press, 2020, ISBN 978-0128161180.
- ↑ Johnson & Robinson, The World Atlas of Wine, Mitchell Beazley, 2019, ISBN 978-1784724030.
- ↑ Ribéreau-Gayon et al., Handbook of Enology, Vol. 2, Wiley, 2006, ISBN 978-0470010396.
- ↑ Stevenson, The Sotheby’s Wine Encyclopedia, DK, 2011, ISBN 978-0756686840.
- ↑ MacNeil, The Wine Bible, Workman, 2022, ISBN 978-1523515327.
- ↑ McGovern, Ancient Wine, Princeton University Press, 2003, ISBN 978-0691070803.
- ↑ OIV, “Wines produced with noble rot”.