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Is the oak industry under threat from rapid maturation techniques?

Moving things along iStock.com/liveslow A look at rapid maturation methods

By Roger Putman fortune, perhaps we should consider what occurs during maturation and judge whether the science behind these It is an oft-quoted old saying, particularly amongst the accelerations is likely to have any com- brandy fraternity, that: “You make brown spirits for your mercial effect. During the preparation of this article, I was told of magic and black sons and daughters and drink the ones your father made.” arts by a number of Scots. Many text This would suggest that it takes time to mature a spirit into books gloss over ten long years in a dark something of which a father might be proud. According to cellar by the Hebridean Sea by saying that the raw spirit fresh off the still is California-based whisky writer, Bozkurt Karasu, Americans diluted to around 64%ABV in casks pre- lack one important virtue – and that is patience. viously used in the US bourbon industry, the angels take their share and hey presto, a few years later the magic hap- ence there has been a lot of inter- wood and if they don’t get that, they are pens after the black arts have weaved Hest lately, particularly in the USA being cheated. All whisky sold in the EU their spells and the blender is presented with its 1000 craft distillers, in produc- must be matured in wooden casks for with something to play with! ing an acceptable spirit in weeks or at least three years, with the defi nition months rather than waiting for years of requiring maturation Wood and brown spirits and suffering concurrent losses of in oak. One can experiment with differ- Brown spirits are matured in wood and volume and alcohol, high stock valu- ent techniques, but whether the fi nal include whiskey, brandies (cognac, ations, on-going warehouse storage product complies with the defi nition of armagnac, pisco, aguardiente and costs and having the Excise breathing whisky in the market concerned (and other grape products) as well as some down your neck all the time. can therefore be described as whisky) is rums, cachaças and tequilas. I note On the more cautious side, Rose- a different matter. Such products would that the innovative souls at Watershed mary Gallagher at the Scotch Whisky have to be described as something else in Columbus, Ohio, fi rst produced a Association observed that “Traditional – they should not benefi t from being barrel-matured gin back in 2012. They production practices have built up the described as whisky.” were surprised when the sale of a reputation of whisky as a category. Con- Before we take a look at the various few bottles was announced and 750 sumers expect whisky to be matured in methods supposed to save distillers a folk turned up to buy some. Hernö in

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Brown spirits of course start off from the still entirely colourless. The brown comes from the oak cask, its charring and toasting and the col- our of any previous incumbent be it bourbon or sherry. Although still a niche category, brand owners see an Char 1 Char 2 angle in acquiring casks that earlier held port, Madeira or wines like Sauternes, Tokaji or even Grand Cru champagne or Chateau Margaux. France’s Brenne farm distillery near Cognac makes a single malt and does things the other way around, starting

Char 3 Char 4 (Alligator char) in new Limousin oak then finishing in newly disgorged cognac casks. Charring the casks at the Independent Stave Company and the various levels of char available, from Char 1 to Char 4 which is the classic Alligator Unaged spirits in the past Sweden has gone further and used a from Longmorn and Glen Garioch with During the nineteenth century, much juniper cask for its spell of maturation. whisky from the Hanyu distillery in whisky was bottled soon after distilla- In the UK, Chris Hayman reports that Japan to produce an offering called tion. But like brewing, whisky-making for his wood-aged 1850 Reserve he Glover. Perhaps on the more bizarre tended to be seasonal in nature and had to alter the gin recipe to take ac- but still eye-catching end of innovation the oak barrel would have been the count of the woody flavours interacting is from independent bottler Caden- most readily available container for with the botanicals. head’s Stupid Cask range with Fishky storage. Discerning producers and I do hope we are not about to see which supposedly put Bruichladdich customers must have picked up on a botanical-infused whiskey but the in a herring cask; pundits Whisky Cast the changed character of the spirit. whole market is highly competitive and were not complimentary, suggesting The current minimum storage period innovation to get that edge in the market that: “The nose hides the secrets of embedded in the Scotch Whisky Regu- is intense. Developing a USP has never the whisky well and the finish is salty, lations is a little known result of Lloyd been more critical. Once upon a time the greasy and nasty with no redeeming George’s efforts to bolster munitions sector was driven only by %ABV, pack- qualities.” Westland Distillery also production during the Great War when age design, age or cask finish. Scottish put out a press release on April Fools drink was apparently causing more products no longer feature as regularly Day with Inferno, finished in a Tabasco problems than the whole fleet of Ger- in Jim Murry’s Whisky Bible top five as cask. Roundstone Rye probably had man submarines. they used to. While at the classic end of more luck with a maple syrup cask. Total prohibition was not an option the market, a 12yo whisky might now be but a number of measures to curb more common than a declared 8yo but Vibrant sector immoderate consumption were intro- there is more and more Scotch on sale So the sector is indeed vibrant and as duced. UK brewers are familiar with with no age statement. In Ireland, Cooley Bill Owens at the American Distilling the restriction of pub opening hours, is selling a poteen straight off the still; Institute points out, if you listen care- making the buying of rounds illegal I trust that it is more potable than the fully to the supply chain for American – and the nationalisation of pubs and product which surreptitiously appeared whiskey, there is a distinct sucking breweries around the munitions plants at times in Bass’ Belfast Brewery! sound as demand threatens to outstrip at Enfield in London and Gretna on the Hybrids are everywhere; Pernod- the ability of the industry to supply. Scottish border – but the Immature Ricard has Zaconey, a blend of Irish and The market is huge, with Bill’s 1000 or Spirits (Restriction) Act of 1915 banned US with berry extracts; Eng- so US craft distillers representing just the sale of any spirit less than two land’s Lakes Distillery produced a blend 1.5% of American spirits sales (over years old. This was increased to three of whisky from all parts of the United there craft beer is 12.2% of the market). a year later. Kingdom called ‘The One’ to sell before We have already seen %ABV reduc- The Act certainly reduced spirit its own whisky comes of age. Moss- tions and a shortening of the period availability and took immature prod- wood finished a 7yo in cask so small wonder that brand ucts off the market believing that they in a cask which had been seasoned with owners are interested in any permitted caused more drunkenness than older espresso coffee. High West Whiskey’s accelerations as long as they do not and obviously more expensive brands. Campfire combines American rye with damage brand credentials. No doubt Today the arms factories are long peated imported Scotch. Similarly Jim much work is going on behind closed gone, but the three-year rule still ap- Beam Kentucky Dram blends Kentucky doors to avoid accusations of penny- plies for Scotch whisky along with the Straight Bourbon with an Ardmore pinching corner-cutting but enquiries to restrictions on raw materials, upper peated malt to ‘marry smoke and va- PR departments are greeted with sharp distillation strength and a minimum nilla’. Diageo’s Whiskey Union recently intakes of breath and quiet tutting alcoholic strength of 40%ABV in bottle. launched Huxley Rare Genus Whiskey, sounds for your even suggesting that Immature spirits disappeared from the comprising Scotch, Canadian and such shenanigans are going on! Heriot market for a century. American casks while its Boxing Hares Watt University in Edinburgh has also The benefits of aging in oak have infuses hop flavours. conducted some research but under a long been appreciated, rather than Adelphi has mixed single malts client non-disclosure agreement. understood. Even today we have only www.ibd.org.uk Brewer and Distiller International November 2016 z 37 l DISTILLATION

Ian Palmer from Scotland’s newest whisky distillery Inchdairnie says he has looked at lots of rapid maturation options, not that he wanted to use them but just to understand them. He tried adding wood into the barrels but this just tasted of sawn wood where the young spirit flavours are masked as opposed to maturing them out. He added “I am looking for complexity, mouth feel, long finish and sweetness. Many of these ideas, for a sophisticated palette, can be just one dimensional which leads to disappointment. Time is only a problem when you do not have enough of it.”

teraction and masking of low flavour heated elements provides a similar if threshold, less desirable characters. less pyrotechnic effect. The tight grain of American oak slows Sherry casks remain popular chemical interactions so the internal although they are no longer procured surface of the staves (not usually the from Bristol bottlers as since 1981, ends) are charred or toasted to create sherry must now be packaged in both a carbon layer and to damage the Spain. Users should note that only wood so that lignin derivatives can be about 90% of sherry casks are derived leached out by the spirit. The staves of from European oak with lighter sher- elucidated parts of it and the discipline uncharred casks have also been dam- ries demanding wood from America – of wood management has emerged aged by heat applied during the curving buyers need to ask the right questions. utilising our current knowledge of a of the staves to make the barrel shape. highly complex and lengthy process. For charring, a gas flame is Making the casks last longer Oak wood is a potent source of vanilla deemed more controllable than the The level of charring, initially carried out and coconut like flavours. traditional fire of oak chippings, with to help mature the bourbon, is still active The continuing popularity of vanilla the intensity of flame and duration when the cask is used for Scotch. It will ice cream is testament to how this spice dictating different levels of charring. remain active for up to five fillings over is inculcated into our flavour preferences Heavy charring can leave a smokiness perhaps 40 or 50 years but each suc- from an early age. Yet it is not all about and acrid taste which is not always de- cessive use exhibits a drop in activity, so adding flavours, there is subtraction, in- sirable. Toasting in front of electrically immature flavours are slower to go and Oak still rules mature flavours take longer to develop. This is best tracked by looking at the colour which is extracted. By carefully choosing the US cooperage supplying the used bourbon casks, it is possible to get a level of activity to suit the product you are trying to mature. After all, if you have to hold stock for a statutory three years there is little point in procuring casks which will have moderated the new-make flavours in two! In the old days exhausted casks would be destined for the garden centre but now they can go through a dechar/ char process where the old layer is scoured off down to bare wood and the surface then charred again with suf- ficient heat to damage the upper wood layer to allow a further few fillings. Con- In Scotland at and Arran and the currently closed Bladnoch distillery ditioning with sherry used to be popular

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but today if you have both grain and malt with oxygen which diffuses through the whiskies, the newly-charred cask is just oak to produce desirable flavour conge- refilled with grain spirit. Otherwise they ners such as acetals. might be used for a ‘finishing’ period Furthermore, the concentration with matured whisky to condition the of ethanol, increased by loss of water wood. There is obviously a limit to suc- to the atmosphere or decreased by cessive dechars before the structural the loss of ethanol if the humidity is integrity of the stave is compromised. high, will complicate the reaction even Balance is essential. A heavily peat- more. For a more detailed review of ed Islay may still dominate the finished the reactions which take place, Ian product even after long maturation Hornsey published a survey in last in a highly active cask. Conversely, a April’s Brewer and Distiller International delicate Lowland would be swamped by and John Conner’s chapter in Inge the use of first-fill sherry casks leaving Russell’s Whisky Technology: Production a cask flavour masking any contribution and Marketing is invaluable. of the stills themselves. Having said New make is typically cut to that the heavy sweetness from sherry 63-64%ABV into cask, there may be is popular with some customers but it temptation to increase this to save on Learning more about maturation conditions. should not be overbearing. barrels and warehouse space but such The front and rear elevations of Buffalo spirit matures more slowly so it will Trace’s experimental 150 cask Warehouse X at Over 500 components have to be in cask for longer. Casks may Frankfort in Kentucky Industry guru Alan Rutherford points be held on their bilges (bellies to the to explore some of the storage issues. out that mature whisky contains over brewer) two high in traditional ware- Warehouse X is comprised of four in- 500 identifiable molecular compo- houses or else on steel racks as high dependently operating chambers that nents, although it is likely that fewer as your building costs and fork lift truck allow specific variables like natural than a hundred of these have a primary reach will allow. More and more will light, temperature, humidity and air- influence on organoleptic character. be conveniently stored on their ends flow to be tested. There is only space These compounds, or congeners, (heads to the brewer) on pallets per- for 150 casks but it uses $1m worth of include higher alcohols, aldehydes, es- haps five high or six high. Temperature monitoring equipment. ters, nitrogen and sulphur compounds, seems to be important and warehouses After a couple of years, results are carbonyls, phenols and lactones. He should be as full as possible to reduce said to be encouraging, yielding ‘inter- groups the long slow chemical reac- fluctuations but casks on the top- esting experimental insights’. Sazerac tions occurring during maturation into most rows will get a lot hotter even in CEO Mark Brown does not believe three general categories. Scotland unless the ceiling is specially rapid aging is the solution to current Firstly, the removal of undesirable insulated. Even in Scotland a steady shortages but he has launched Whis- or immature components such as heavy 2% of volume is lost to the angels every key Thief – a bourbon with added oak sulphur compounds by absorption on year meaning that after ten years only inserted into the barrel. Such contact to the oak/char surface and to a lesser 85% of the volume will remain but the is said to double the age profile of the extent by evaporation (light carbonyls) loss of water being relatively greater product. Meanwhile Buffalo Trace is to through the porous wood. Then desir- will usually slightly elevate the %ABV. spend $200million on capacity expan- able components such as lactones mi- sion at its Frankfort base in Kentucky. grate from the oak to the spirit. Finally Experimental warehouse there is chemical interaction within the Sazerac opened its Buffalo Trace Reducing the raw new-make spirit between organic compounds and Experimental Warehouse X in late 2013 flavours A large company like Diageo with 28 malt distilleries has to know the char- acter of the various new-make prod- ucts in formulating a wood manage- ment policy. These flavours may range from perfumed, appley, grassy or fruity to cereal, sulphury, feinty or smokey. This immaturity is attenuated to yield a desirable product over time before the whisky is deemed saleable and can be passed on for blending. Newer producers should look at the materials and processes which might lead to the new-make product being more pun- gent, sulphury and feinty thus needing a longer maturation period. One Speyside distiller I spoke to was most affronted when I suggested his new-make was pungent, raw or feinty. Three casks sit in the firing chamber at various stages of the charring and heat treatment as Clearly he has a finely-tuned process, part of cask rejuvenation he thought he would get the sack if www.ibd.org.uk Brewer and Distiller International November 2016 z 39 l DISTILLATION

Maturation in action it wasn’t and the spirit was not ready Maturation effects on the 1096th day after filling. Others might choose to alter the wash condi- tions considering the wort clarity and concentration, totally enclosed or open, stainless or pitch pine fermenters, pitch Distillery Character Interactive rate, type of yeast used, pitch tem- perature, wort oxygenation and period Spirit

Character in fermenter. All will alter the volatile Immaturity Maturity compounds present in the wash. Within the still, the ‘copper conversa- Subtractive Additive tion’ is critical as active sites on the sur- face will remove sulphury compounds. Time These active sites will get used up like a This diagram from Diageo illustrates how the maturation process attenuates the raw spirit spent Brillo pad and need rejuvenation immaturity over time, the distillery character interacts with the wood which also develops by resting the still, opening the hatch to maturity traits – all over time allow air inside and also having a gap be- tween one distillation and another. There Maturation effects - Maturation effects - initial high level of immaturity low level of initial maturity must be some mileage in the nano par- ticle copper surfaces espoused by Italy’s Green Engineering (Brewer and Distiller International, June 2016) as surface area Distillery Character A Distillery Character A for reaction is increased dramatically. Spirit Spirit Character Character Distillery Character B Distillery Character B Still design with respect to the angle of Immaturity Immaturity the lyne arm, the reflux geometry in the neck and the temperature of operating Time Time the condensers so that if they run hotter These slides show higher levels of immature character take longer to attenuate with the vapour condensing further down the worm so that there is more spirit Maturation effects - Maturation effects - vapour ‘conversation’. exhausted cask highly active cask Then there is the generosity of the cuts from foreshots to spirits and then to feints. Whether there are separate Distillery Character A Distillery Character A tanks for foreshots and feints and Spirit

Spirit the way these recoveries at different Character Character Distillery Character B Distillery Character B ethanol concentrations react with the Immaturity Immaturity still all have an effect. It has always Time Time amazed a humble brewer how these An exhausted cask will remove immaturity far more slowly than a reactive one unwanted compounds go round and round the process yet somehow the levels remain in balance and you do Maturation effects - Maturation effects - exhausted cask highly active cask not get the accumulated methanol from operations since stills were legalised in 1823! Scotland is a relatively small area Distillery Character A Distillery Character A compared to the United States or Canada Spirit Spirit

Character Maturity Character Distillery Character B Distillery Character B where temperatures can easily range from 30oC in summer to -30oC in winter. Maturity Eight thousand feet up in the Rockies in Time Time Colorado will see a 20% evaporative loss; Similarly, the maturity level in an exhausted cask will build more slowly than in a highly there you will see casks covered in large reactive one plastic sheets and misters trying to keep the atmospheric moisture up. There Maturation effects - Maturation effects - are over a hundred Coloradoan craft exhausted cask highly active cask distillers, situated over 5000 feet above sea level, tackling challenges unknown at sea level but with many Americans Distillery Character A Distillery Character A tracing their ancestry back to Scottish Spirit Spirit immigrants, the draw to produce a tradi- Character Character Distillery Character B Maturity tional Scotch is high indeed. Immaturity Immaturity Maturity Time Time Oak is big business Putting the two effects together, you can see the slow loss of immaturity and the slow gain of The Scotch Whisky Association reckons mature character in an exhausted cask compared to the more rapid reduction in raw flavour and there are 20 million casks matur- increase in mature flavour to a higher level if the cask is more active ing spirit in Scotland. I am told that a

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commercial rental for a cask is around degradation products (such as vanillin, istic of aged product’. A 1976 patent £15 per year. Applying that figure syringaldehyde and coniferaldehyde) from Belarus proposes that staves are across the industry shows how storage provide floral, spicy, smooth, mellow placed in a vessel under vacuum for alone amounts to a not inconsiderable attributes to flavour and aroma. Tannin half an hour to remove most of the air sum. The whisky market worldwide is contributes to bitterness and astrin- from within; gaseous NH3 is introduced around 11.5% of the total spirits market gency. Subtractive reactions include under a pressure of 1bar and the (3127m 9L cases), so add the brandy evaporation of volatile compounds staves are held for 0.5-5 h at 20-35°C and rum casks, all the wine casks and such as ethanol, acetaldehyde and in an alkaline medium, in which oxida- even Tabasco, Worcestershire Sauce dimethylsulfide. tion with O2 is carried out at 20-35°C and maple syrup barrels, you have an Oxidations involve ethanol to for 0.5-3 days. Excess NH3 is removed awful lot of wooden containers. acetaldehyde and dimethylsulfide to under vacuum. Today the brewing contribution is dimethyl sulfoxide and ethanolysis John continues: “From a Scotch negligible with traditional producers like of acrolein to 1,1,3-triethoxypropane. whisky perspective, there are two prob- St Austell, Wadworth and Sam Smiths Productive or interactive reactions lems with the first method. A big stick- as well as kolsch makers in Cologne include oxidation of acetaldehyde to ing point is that most Scotch whisky still using a few casks. It is thus hardly acetic acid, esterification of acetic acid is matured in used casks and this is surprising that one of the earlier papers to ethyl acetate. Acetal formation from virtually impossible to mimic using oak exploring rapid maturation appeared in acetaldehyde and ethanol, oxidation sticks. The chips provide a rapid and a journal called Forestry back in 1985. and esterification of lignin degradation almost complete extraction whereas Oak is a large industry. A tree might take products and water-ethanol interac- the physical structure of the stave plays 80-120 years growing tightly together to tions through hydrogen bonding lead- an important role in regulating the ensure a tall straight trunk. The timber ing to the formation of stable clusters extractives that dissolve in the spirit. below the first branch is taken and that of water and ethanol and an increase “Also, we have very limited informa- might only yield enough wood to make in viscosity. Stable clusters of water tion on how wood extractives change two or three casks. English oak is said and ethanol are thought to contribute over the course of maturation. Without to be too knotty although that did not to the ‘mellowness’ of the spirit. this knowledge it is impossible to say seem to bother Admiral Nelson and the Maturation enriches the sensorial whether the various methods in use shipbuilders at Chatham Dockyard. characteristics of the product through accelerate these reactions, so what you The vast majority of casks used for reduction of DMDS and DMTS from have added is extract and not mature whiskey are sourced from the USA. grain and ‘nutty, cereal, oily or feinty’ character. Stateside regulations demand that characters of new-make spirit. All this I have similar reservations about whiskey be matured in a new cask, complexity suggests that any attempts the methods used to reduce immature which leads to the availability of a at acceleration are not likely to deliver characteristics. “Again we do not know large number of second-hand casks. an absolute match to any traditionally enough about these reactions to say The Scotch industry has based its matured product. whether they are accelerated by the strategy around this continuous supply. John Conner, the Scotch Whisky various methods. Increasing the energy Another April 1st post in 2014 sug- Research Institute’s maturation guru input in whatever form or the use of gested that Diageo and Brown Forman divides the approaches into three. catalysts may not just accelerate reac- were tussling with US regulators (The First is what amounts to the addition tions that would naturally have taken Alcohol and Tobacco Tax and Trade of wood extracts and this can take a place, but the chemist in me can’t help Bureau – TTB) over the definition of multitude of forms depending on the thinking it could help others over Tennessee whiskey with B-F wanting required character: American v French their activation energy barrier to allow the second use of a cask. oak, the degree of toast, staves, cubes and put in motion reactions that This would solve any US cask or chips and whether soaked in wine. wouldn’t normally occur.” shortages but the supply of cheap The use of ultrasonics is simply a IBD whisky tutor Brian Eaton casks for Diageo’s 30 Scottish plants way of increasing the rate of extrac- adds: “There are other matura- would dry up – putting pressure on us- tion. The second camp concentrates on tion effects that cannot easily be ing casks more economically. A scary the removal of immature characters mimicked – the loss of volatiles spoof perhaps, but could it happen? and a variety of techniques appear to and oxidation. This was shown be used – activated charcoal, light and Speeding things up metal catalysts. We have had a thorough look at the Lastly there are one or two patents challenges of more traditional cask espousing the ammonium ion but Dr maturation, so how can this be accel- Conner is at a loss to think of any rea- erated? Imitating maturation is rather son this would promote a naturally oc- challenging in view of complex multi curring reaction. The patent describes stage and subtle processes. A quick the background as ‘alkaline distillation recap might be helpful. causing protein hydrolysis and amino + During maturation, additive, sub- acid deamination, the resulting NH3 tractive and productive mechanisms ions react with the naturally present operate which change the colour and aldehydes to form ammonium alde- the flavour of the new-make spirit. The hydes. These in turn enter into aldol Tuthilltown Distillery in New York State were early main groups of compounds extracted condensations with the esters and/ exponents of maturation in smaller casks using 3, 5, 10 and by spirit from oak are hemicelluloses, or the congener molecules to give the 14 gallon barrels. Even the bottle for its Baby Hudson is lignins, tannins, and lactones. Lignin complex aldehyde mixture character- small at 375mL www.ibd.org.uk Brewer and Distiller International November 2016 z 41 l DISTILLATION

ture identical or artificial and referred to as GRAS (Generally Recognised as Safe). Several of the components imitate the composition of congeners formed during fermentation which would be released into the spirit. These would be esters notably ethyl acetate ethyl caproate, ethyl caprylate, ethyl caprate, ethyl laurate, isoamyl acetate and phenylethyl acetate, which impart diverse fruity and flow- ery notes. Small amounts of other chemical compounds such as higher alcohols/fusel oils, fatty/organic acids and aldehydes are also incorporated to provide a balanced product character and palate appeal. Flavour houses can supply treat- ments containing some of the critical components developed during the maturation process such as furfural, vanillin, lactone, eugenol, guaiacol etc, but incorporating tannin and phenolic aldehydes such as coniferaldehyde, sinapaldehyde and syringaldehyde in appropriate proportions is often a limiting factor.

Staves, cubes and chips Innerstave products are typical of oak inserts: Most accelerators will use wood in the staves installed in a vessels, a fan of slats for form of staves, cubes or chips. There suspension in a cask, a nylon bag of ‘blocks’, a is a choice of oak and toasting. Andre chain of toasted laths fits into the barrel and Alcarde at Brazil’s Sao Paulo University oak cubes tested chips with cachaça and found it pop-up all over the country they also made no difference whether the oak adapted this method. Ralph and Gable was American or European but toast- Erenzo at Tuthilltown Distillery started to ing levels did. Wood to make a matrix use three- and five-gallon casks allowing of staves within a tank or just cubes or a few years back with shrink-wrapping them to bring their Hudson Baby Bour- chips are available from Independent of casks in Scotland with the aim of bon whiskey to a colour and taste profile Stave, Oak Wise and Innerstave. minimising alcohol loss – the whisky at a decent level in under six months. A This latter company, based in Cali- did not mature well. It has also been lot of distillers are using the micro-oxy- fornia, is typical, with a choice of oaks found recently that stacking casks genation method – again inspired again and toast levels – toasted staves can on pallets instead of on their bel- from the wine industry. Those micro- be mounted inside tanks where 1.7 m2 lies increases the time required for oxygenators are not that expensive to will mimic a 225L cask, they can be in maturation by about a month per year, buy. They pump medical oxygen into the the form of a fan of 22 laths measuring presumably due to poorer air flow barrels in intervals to oxidise the spirit 28x2x5/16” which can be dangled in on around the cask. So it is not just about like it would over the years. a chain. Shorter laths can be drilled adding wood character.” Another method is the pressure and linked so that a chain of 17 can cooker invented by Tom Lix at Cleve- be used and each mimics a third of a What has been tried? land Whiskey. He puts some wood barrel. Half-inch cubes suspended in a There are lots of cautions out there but chips and staves in his spirit in a big nylon mesh bag with a drawstring and perhaps you would expect those con- pot and alternates the pressure low a sack with 6.3m2 surface will treat 600 nected with an industry where there is and high over several days.” gallons within the year. Chips the size tremendous heritage and a strict legal Smaller casks alter the surface to of broken matchsticks are used at 10 time limit to be apprehensive but let’s volume ratio. Buffalo Trace reported to 20 pounds per 600 gallons, they too see what has been tried. Bozzy Karasu back in 2012 that trials with small can be contained in a nylon bag. takes up the story: “To start with, using casks (5, 10 and 15 gallons) over six Infusion Spirals, part of the Barrel any cask size smaller than standard years were not successful citing a lack Mill Cooperage, increase the surface 53-gallon barrel is for one goal only: of depth of flavour. area by milling a spiral configuration accelerated maturation. It is a method At the budget end of the market in into 48-inch long poles around 30mm in perfected over the years in the wine India, commercial flavours are added diameter. Five in a mesh bag will treat industry and they have been pretty to molasses-based neutral spirit to 1000 gallons. Nine-inch lengths can successful with it. make cheaper whiskies. These added form a chain inside a long nylon bag When craft distilleries started to flavours are classified as natural, na- and six of them are said to mature 70

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day inside a bottle of neutral spirit to with a cask of the make a passable whisky. You can buy a same brew flown 750mL oak bottle from Amazon to keep out from Burton. your vodka in and surprise granddad In the whiskey at Christmas! Thousand Oaks Bar- world, Jefferson rels in Virginia will make you a cask Bourbon recreated from one litre size upwards and also the route used 150 supply a range of essences if you really years ago from want to cheat! Independent Stave can Louisville down the make casks with up to five different Mississippi across types of oak wood to give you the best to Florida and north of all woody worlds and Makers Mark to the East Coast – offers private customers the chance and went on to take to formulate their own barrel in a new a cask between five program called Private Barrel. continents cross- A number of distillers use chips ing the equator within a conventional cask. Copper Fox four times to see in Virginia which incidentally floor-malts whether ten months its own barley, pops a mesh bag of oak on water would en- Joe Paglioni’s Oak Bottle claims to ‘infuse’ and apple chips into the bourbon barrel hance seven years spirits with the same amount of flavour as with the whiskey. After the year, the chip in a warehouse on lengthy barrel ageing C&C Shine’s Californian bag is removed and reused, then the dry land. (from a Kentucky recipe) came with gallons. Different oak sources and toast- whiskey is transferred into another bar- French whiskey a toasted oak rod. This is placed in ings can be used together. The company rel which is heated and then rolled, still maker Black Moun- the bottle which can be regularly also makes smaller diameter spirals hot, to ensure that the alcohol achieves tain strapped a 280L tasted to assess how long it takes which can be inserted into bottles. maximum penetration into the charred cask to the deck of a to obtain the wood flavour you like Time and Oak sell small toasted internal layers of the barrel. After sailing vessel which took tourists around sticks branded Whiskey Elements cooling, the process is repeated several the Bay of Biscay. It was on board for six which are cut to increase surface area times over the next few months until the months. A 300L cask of Jack Daniel’s and apparently need only to spend a spirit is ready for bottling cocktail as formulated by the Savoy in London was on the open deck of the The effect of long journeys Queen Mary II for a 41,000mile trip lasting Agitation could be a factor. There have four months. Last year Suntory put some been various publicity stunts like Pete whisky (not in barrels) on the Interna- Brown trying to take a cask of Burton tional Space Station in a maturation IPA to Calcutta until it disgorged its experiment echoing the Ardbeg exercise contents all over his hotel room in which kept vials of Islay congeners grav- Brazil. The idea was to take the beer ity free for three years. The continuing on a six-month journey and compare it saga allowed the release of several top end offerings celebrating the 90-min- ute circumnavigation of the weightless Time and Oak claims its Whiskey Elements containers – we await the results. sticks add the effects of three years of ageing Going not quite as high we have to any whisky in just 24 hours seen Montanya Rum matured at 8,900 feet up in the Rockies inspired by some Columbian rum which was kept at 17,000 feet. A day at Crested Butte in Colorado can see temperature fluc- Oak spirals from Infusion Spirals… tuations of 40oC! Meanwhile, Cayman Spirits Company’s Seven Fathoms Rum matures at a depth of 42 feet under the Caribbean Sea. The motion of the tides gently rocks the casks and the company keeps the location a closely guarded secret. We know the wood ‘breathes’ allowing oxygen and other molecules out, so is the micro movement allow- ing the layer of liquid close to the stave to mix with the body of the cask and avoid concentrations which might slow reactions. How many distillers roll their casks before sampling? Is there A bottle spiral kit you can use in spirits, beers a concentration gradient in the liquid or cocktails or oak chips from Add Oak towards the wood surface? www.ibd.org.uk Brewer and Distiller International November 2016 z 43 l DISTILLATION

Agitation in action. reheated to 60-75oC to finish off the operation. Terrapure from Terrassentia based in South Carolina makes claims for a similar system which uses ultrasonics and pumps new-make through an oxy- genated chamber. It offers own-label spirits to some 50 hotel and restaurant chains but details of the actual process are currently rather vague. The Allegro process from Kairos Global also offers a reaction vessel un- der controlled temperature and oxida- tion conditions passing spirit through a comminuted wood matrix. Kairos offers a service to match the ethyl Jefferson took two casks from Louisville to New York by sea and then took another cask acetate in a matured product which on a voyage visiting all continents crossing the equator four times. Seven Fathoms from might take four years by incorporating the Cayman Islands is matured 42 feet down in the Caribbean an addition into the reaction. The wine industry has tried passing Listen to the music Thea One electric currents in the presence of The boys at Tuthilltown There are a number of patents for oxygen through young acidic red wine also installed sub-bass ultrasonic treatments to hurry the and reported more mellow and aro- speakers into their molecules along a bit but apart from matic results. Three minutes produced warehouses to give the Terrapure, tests do not seem to have the best wine while anything over eight barrels some rumble got beyond the laboratory bench. There yielded a product worse than the con- so that the magic at is one high-energy input system which trol. Pulsed electric currents have also the air, wood and spirit is causing a bit of a stir despite the shown encouraging results. Rice wine interfaces can be en- inventor getting a pretty rough ride at has been reportedly enhanced by both hanced. Copper and Kings, an ADI symposium. γ-radiation and ultrasonic treatments. a brandy distillery in Kentucky says its Bryan Davis has spent years inves- Any application to spirit maturation casks prefer the works of Lenny Krav- tigating the aging of spirits. He first has yet to be published. itz, The Doors and Bruce Springsteen founded an absinthe operation in Spain Bozzy gets the last word: “I have to stretch their pores. New Zealand gin and moved back the States to make tasted hundreds of spirits that went maker Rogue Society has also experi- whiskey at a plant called Lost Spirits through accelerated aging one way mented using a local band and you get beside the Pacific at Monterey. He had or other; they have a different taste a CD of the ‘music’ when you buy the a wooden still, obviously steam heated, profile you can get right away. But it is Electric Wire Hustle X Rogue Society and the worm passed through his not necessarily bad. Anyway, they do Gin Limited Edition. swimming pool so that he could have a taste different – exactly like small bar- relaxing dip after the run! rel wines do. Distillers should not try With the help of crowd funding he to match the flavour profile of longer launched Lost Spirits Technology and maturation periods of Scotch distiller- built a portable reactor which claims ies. It is a fight they cannot win. Noth- to make a good quality spirit in just six ing can replace longer maturation in days. He has impressive GC-MS charts bigger barrels in milder climates. They to show that the peaks are all in the use a different method which leads to right places. His board boasts some a different taste. retired industry heavyweights, there “Be OK with it, craft distillers have are five prototype installations chris- a six-month old whiskey matured in tened Thea One in operation and he a different way and tastes different. is in talks with another 65 distilleries It is a new product, maybe a new cat- looking at forming a partnership. Thea egory – and they should work on how One will produce over 500L of ‘20yo’ to make that unique product better. I each week. think we have all learned that in this New-make spirit and oak chips industry, we cannot replace time with are put in the reactor. The process smart ideas.” first involves a heating spell under just 6psi top pressure at tempera- Acknowledgements tures between 60-75oC. The spirit is The author would like to thank Bill cooled and subjected to light ra- Owens, Margarett Waterbury, Gra- diation from 400-1000nm passing ham Stewart, James MacTaggart, over 2m lux hours. Putting a carboy Ian Palmer, Alan Winchester, Gary Colonial American Inspired Rum at 62%ABV from the Lost in a Californian greenhouse for a Spedding, Binod Maitin and Douglas Spirits Distillery in California – oak matured in the Lost week would pass just over 4m lux Murray for helpful direction during the Spirits reactor (inset) hours. The light treated spirit is then preparation of this article.

44 z Brewer and Distiller International November 2016 www.ibd.org.uk