February Outturn 2025 Feature Article
Mighty Oaken Cask chapters on Sherry Butts (#4) and Seasoning & Treatment (#6) allude to the popular whisky cask rejuvenation technique now known as paxarette. This Scottish innovation is a much-misunderstood and abused term coined in the 1970s by wine writers derived from a Spanish winemaking technique. This sherry cask treatment played a major role in developing Scotch and Irish whisky from the late 19th century until the late 20th century.
Ex-sherry casks were the vinous flavour bridge that transitioned English brandy and wine drinkers into whisky. Since the 19th century, the trade classification and consumer acceptance of whisky was ‘Sherry wood is said to yield a peculiar and desired flavour to whisky, imparting a deeper colour hereto than plain wood. Whisky made in this manner is Genuine Scotch.’ In the formative days of sherried whisky, ex-sherry butts were almost inert of oak flavours, as winemakers minimised the presence of wood to enhance wine flavours. Sherry bodegas dissipated tannin and oak compounds in new oak containers by exhausting the wood for a decade or more, utilising grape must vats and fermenting vessels before exposing their wine to the spent stave wood. This oak-spent, sherry-infused cask flavour shepherded the adoption of whisky in Britain and exports throughout the Empire.
The word paxarette originates from a sweet wine first produced in Pajarete (multiple spelling variations, Pajete, Pacaret, etc.), a region in the Province of Cadiz, neighbouring Jerez de la Frontera, the home of sherry. Pajarete winemakers, in the late 17th century, left Muscat and Gibi-Millar grape harvests on mats to be sun-dried to intensify the sugars or Baume level before fermenting and exporting to Britain and the American colonies, which commanded premium prices. Neighbouring wine districts of Malaga, Jerez, and Seville adapted this sweeter style with variations. Jerez added the Moors method, a culinary formula that traces back to Pharaonic Egypt and Ancient Greece, creating sweet grape syrups called arrope and sancocho. By the late 18th century, syrup added to the sherry produced a more pleasing colour and flavour called color de macetilla.Jerez bodegas used Pedro Ximenes and Palomino grape syrup in their oxidised wines to bolster their Amontillado, Oloroso, and Palo Cortado to Pedro Ximenes styles of sherry style wines. Jerez bodegas developed recipes using sweet grapes and adroit techniques to reduce their syrup over twenty-four hours.
England had been sherry’s principal export market since the 14th century, and between 1820 and 1860, England imported 87% of sherry’s export trade. It became Britain’s favourite wine, and from 1860 to its peak year of 1875, imports doubled to 6.8 million gallons (31 million litres). Maturing malt spirits in ex-sherry casks was the sensory breakthrough for Scotch whisky, making it a more desirable and complex product than storing malt or grain distillate in ex-rum, ex-brandy or other containers. After 1875, sherry began its long and deep decline in Britain, while whisky rapidly became Britain’s leading distilled spirit, leading to chronic cask shortages; sherried whisky might have been responsible for further cannibalising sherry consumption. Aggravating the shrinking delta of imported sherry casks, distilleries and wholesalers preferred older and sweeter butts, once holding Oloroso and Pedro Ximenes, avoiding drier biologically aged styles like Fino and Manzanilla sherry. Remedial solutions were introduced when distilleries and cooperages started a new practice by aggressively treating virgin casks with heated water, pressurised steam and caustic chemicals to extract and minimise the oaken flavours to store new whisky distillate for a couple of years before flavour embellishing in ex-sherry casks for several years. Most whisky was cask-aged for five to eight years.
To extend the useful life of ex-sherry casks, another solution was developed in the late 1880s, resulting in the Lowrie, Barr & Scott’s patent of October 1890, the process of injecting sherry through the bunghole under steam pressure to wine-infuse exhausted casks. Lowrie was the largest whisky wholesaler in Scotland, owned cooperages and blending houses, and was an agent for the leading sherry house, Gonzales Byass. The Scottish patent replaced William Thompson’s Dublin’s Prune Wine Extract, which added pleasing pseudo-wine flavours and colouring to many Irish, Scotch, and Australian whiskies since the late 1860s. William Lowrie’s pressurised wine treatment was used widely until the late 1980s to enhance the sherried flavour of Walker’s, Dewar’s, Buchanan’s, and countless Scotch brands.
Distilleries seeking to continue to bottle ‘genuine Scotch whisky,’ ergo sherried whisky, faced the continuing shortage of ex-sherry casks throughout the 20th century due to wars, changing fashions and economic cycles. By the 1970s, the shortages had become so acute and costly that distilleries like Macallan began acquiring cooperages in Jerez to ensure supply. Even though the greater bulk of sherry was bottled in Spain, when Spain joined the European Union, the Spanish government banned shipping bulk casks in 1986 to prevent adulteration by fraudulent overseas agents. Britain’s 1988 Scotch Whisky Act, adopted in 1990 as the EU Scotch Whisky Order, contained a blanket ban on additives, including traditional sherry wine cask treatments. Paradoxically, the foreign additive, E-150a/c, usually made from cane sugar, was permitted in the Act as caramel colouring for Scotch.
The sherry bodegas and cooperages responded to the whisky industry’s insatiable demand for sherry casks by filling new oak casks and soaking low-quality sherry for six to eighteen months before shipping wine-infused casks to contracted wholesalers and directly to distilleries. Wine regions outside the Jerez sherry triangle and unscrupulous agents inundated the market with ersatz-soaked casks. In 2015, the Cosejo Regulado set at least twelve months to soak sherry casks in the Jerez zone; however, this is self-regulated and not an enforceable standard.
Beguilingly, the flavour profile of sherried whisky has gone through several noteworthy taste modifications due to changing cask treatments, from the original sherry-intense butts to the modern oak-laden hogshead ‘sherry bombs.’
- From the 1780s to 1870s — Inert sherry butts with minimal oak presence (almost exclusively American white oak) maximised whisky’s vinous flavour characteristics.
- From the 1880s — Specially treated plain new oak purged of tannins and oak flavonoids (mostly white oak), often sequentially filled in paxarette-treated older sherry casks to enhance flavour amelioration.
- From the 1980s — New, virgin casks, briefly sherry-soaked, resulted in more pronounced oaken flavours and tannin astringency with drier mouthfeel.
Australian coda: In 1993, Tasmania’s first micro-distillery, Small Concern, soaked its 200L ex-bourbon barrels in local sherry for two weeks (reclassified apera in 2010), repeating the flavouring treatment widely practised by Australian whisky distillers since the 1860s, and is continued by other distilleries today. Only Scotland banned this treatment on home soil, permitting bodegas and cooperages to continue this traditional practice of conditioning casks with sherry before shipping to Scotland.
This is the 7th instalment of Chris Middleton’s ‘Mighty Oaken Cask’ series, an in-depth series looking at wood in all its forms in relation to whisky maturation. You can read the previous instalments here.
This article is featured in the February 2025 issue of Outturn Magazine — bottles will be available to purchase on Friday the 7th of February at midday AEDT exclusively to members of The Scotch Malt Whisky Society. Not a member? Click here to learn more about the world’s most colourful whisky club.
