It’s among the most frequently-asked questions we field: what is a VDN?

The short answer is that ‘VDN’ stands for the French term ‘Vin Doux Naturel’ – literally ‘naturally sweet wine’.

Alongside First Fill and Virgin American Oak, and Premium French Oak, VDN casks make up the four pillars of our Good Wood portfolio.

But why, in a world in which oak is probably the most talked-about element of whisky, is the term ‘VDN’ so unfamiliar?

A word, first of all, on those naturally sweet wines themselves.

‘Naturally sweet wine’ is actually one of the great misnomers of the drinks industry. Unlike conventional sweet wines – Sauternes, Tokaji, Trockenbeerneauslese – whose sweetness derives from an original gravity too high for yeasts to ferment to total dryness, Vin Doux Naturel gains its sweetness through a process of ‘arrested fermentation’, by fortification with alcohol.

The home of VDN is the south west of France, particularly the small appellations of Maury, Banyuls and Rivesaltes. The most important grapes are Muscat à Petit Grains for white wines and Grenache Noir for red, but various other varieties can be and are used.

Just like sherry or Port, during fermentation spirit is added, raising the alcohol level beyond the which yeast can operate, leaving unfermented sugars in the must. The wine is thus both sweet and between 15-20% ABV

The wine is then matured in barrels, where it is subject to a micro-oxidative process that sometimes lasts decades before bottling. There’s no intention for the flavours of oak to play a role in the wine; the casks are old, relatively neutral vessels. Over the long years of maturation however, the VDN seeps into the staves of the casks themselves, imbuing them with new, rich, sweet flavours. It is these flavours with which we are looking to augment our single malt; natural sweetness rather than the short-cut additive of E150a Caramel Colouring.

Why so few and far between?

Before the seventies wine casks of all stripes were commonplace in the whisky industry. Until then, almost every wine consumed in Ireland and the UK arrived in casks for local bottling. To clear the docks and decks, emptied casks were despatched to grateful distillers. Wine casks, often of French and Spanish oak, were near-ubiquitous in Scottish and Irish distilleries.

A perfect storm put paid to all that. Sherry fell steeply out of fashion after the 1970s, and indeed consumption of all post prandial fortified wines dropped markedly, partially as a result of tightened drink driving laws, partly age demographics. The final nail in the coffin was the outlawing of bulk exports of sherry in 1981 – by which time the practice of shipping casks from anywhere had, in any case, all but disappeared.

The results, for the whisky industry were significant. Paxarette, a darkly concentrated sweet gloop, a combination of poor quality sherry with ‘vino de color’ – a sweetening and colouring agent made from concentrated grape must – was trialled as a replacement, before it was outlawed. More often, distilleries would simply reuse old sherry casks over and over again, long past the point at which they could impart any flavour. As long as they originated once upon a time from Jerez, as long as they were called butts – no matter how exhausted or denuded of impact – the word ‘sherry’ could be added to the label, the appearance mimicked by E150…

Ironically, the fashion for sherry wood-fetishisation in the whisky industry has moved the industry to a point where whisky labelled ‘sherry cask’ suspiciously outsells sherry itself. The so-called ‘seasoning’ of casks – ‘sherry’ casks made in Jerez specifically for the whisky industry and ‘seasoned’ for a brief spell with a bottle or two of a sacrificial wine, before being sent to distilleries. Our preference is to use the real McCoy – barrels that have been part of true sherry solera systems – but these genuine sherry casks are few and far between. Hence using only a small handful of the very best we can find.

The wine connection

Our roots in the wine trade go deep. Our founder, Mark Reynier, worked in fine wine for twenty years before joining the whisky industry, and we’re extremely lucky in the connections we have with world class wineries as a result. We speak the same language.

Oak is too important to compromise on, so we go direct. Indeed when Head Distiller Ned was visiting one of the wineries we get VDN casks from, they remarked that it was the first time a distiller had come to see them. The casks we get as a result are second to none.

These casks give us natural sweetness, a sucrosity leached from the wood by the spirit that simply can’t be replicated through any quicker, cheaper methods. Though they augment seamlessly into our whisky – one VDN winemaker commented that he couldn’t taste the wine itself – their absence would be felt enormously.

VDNs are some of our most expensive, hard-to-source casks. But they play a critical part in the balance and character of our whisky.