I recently tasted a sample, generously provided by Compass Box,  off “The Circus” and this whisky is a blend of multiple (duh!) parts. I Like this whisky a lot. Since I am not a trained nose nor palate I will just stick to superlatives like “Wow, this stuff is beautiful”.

Compass Box “The Circus”

I do however taste tastes and smell smells that I think I know. One of these influences that people say I should be able to pick up is the “Sherry” influence on this dram.

The information provided about the four component parts of this dram all makes reference to some form or another of maturation in a “Sherry Butt”.

Compass Box “The Circus”

This “Sherry” reference sparked a question in my mind, or actually a train of questions.

Questions like:

  • What is the influence of maturing in a “Sherry Butt” on a whisky?
  • What is a “Sherry Butt”?
  • What is “Sherry”?
  • How is “Sherry” produced?
  • Are there, like for “Whisky” any legal definitions and regulation that govern the product and the process?
  • What is actually left over in the barrel of the “Sherry” that was ones in it?
  • What chemical reactions, if any, take place after adding a Whisky to a “Sherry Butt”?
  • How are these reactions different from “general” maturation like “first fill ex bourbon” cask maturational?
  • What do the answers to all these questions teach me about “Sherry notes” in Whisky?

This blog will be a “growing” document on what I learn in the coming weeks, months and years to come. It will be loads of fun, since I already stumbled on hearty discussions amongst “experts” what the influences are. I will totally ignore all these and find out for myself! Fun!!

What is the legal definition of “Sherry”?

As with whisky there are European Union Regulations that set the legal definitions for some wines produced in some member states. Article 59 of COMMISSION REGULATION (EC) No 607/2009 provides a derogation.

In accordance with Article 59(3)(b) to Regulation (EC) No 479/2008, the terms ‘protected designation of origin’ may be omitted for wines bearing the following protected designations of origin, provided this possibility is regulated in the Member State legislation or in the rules applicable in the third country concerned, including those emanating from representative professional organisations:

Article 59 of COMMISSION REGULATION (EC) No  607/2009
Article 59 of COMMISSION REGULATION (EC) No  607/2009

What I deduct from this is that “Sherry” is a regionally protected spirit/wine just like “Scotch Whisky” is.

It is just as regulated as “scotch whisky” by unique local traditions. To clarify. “Wine” as a general type of spirit equals “Whisky” as general type of spirit. “Sherry” as a regionally protected sub-type equals “Scotch Whisky” as a regionally protected sub-type. “Oloroso” as a kind of “Sherry” equals “islay barley” as a kind of “Scotch Whisky” as a kind.

Side thought:
As a side thought, please read the next line and see if tells you anything, if for instance, an “oloroso” maker would state on the label the following text:
  • “15 yo Oloroso finished in a “Scotch Whisky” barrel”.
Now read:
  • “15 yo Single Malt finished in a “Sherry” butt”.

Even though a whisky drinker would recognise the last line immediately, a whisky drinker would also recognise the limited use-fullness of the first line. It really doesn’t say much if you just say “Scotch Whisky”.

Would a Sherry drinker make the same appraisal of the last line? Would he also say that stating “Sherry finish” really doesn’t say much. I would have to say “most likely yes”.

What would be more useful in the mind of a whisky drinker would be a description on a Oloroso Sherry like:

  • “15 yo Oloroso finished in a “Laproaig 10 yo first fill bourbon barrel”.

This really cannot get more detailed as a disciptor, but what would it say about the Sherry to a Sherry drinker that has limited working knowledge about whisky?

What is an Oloroso Sherry?

Since Sherry is apparently a type of wine, this means that Oloroso is a category within the kinds of Sherry’s. According to PART A — Traditional terms as referred to in Article 54(1)(a) of Regulation (EC) No 479/2008 the definition of a “Oloroso” is;

Liqueur wine (vino generoso) of ‘Jerez-Xérès-Sherry’ and ‘Manzanilla Sanlúcar de Barrameda’, ‘Montilla Moriles’ which possesses the following qualities:

  • much body,
  • plenty and velvety,
  • aromatic,
  • energetic,
  • dry or slightly led,
  • of similar color to the mahogany,
  • with acquired alcoholic strength between 16 and 22o.
  • It has been aged during at least two years, by the system of ‘criaderas y soleras’, in oak container of maximum capacity of 1 000 l.

This definition is not an opinion, but the legal definition of a “Oloroso Sherry” Liqueur Wine. I have identified some parts that I find particularly interesting for finding the taste and nose influences on a “Olososo Sherry Matured” whisky.

Next to Oloroso multiple other ‘Jerez-Xérès-Sherry’ types are identified in the same appendix:

  • Amontillado: Liqueur wine (Vino generoso) of ‘Jerez-Xérès-Sherry’, ‘Manzanilla-Sanlúcar de Barrameda’, ‘Montilla-Moriles’ dry PDOs, of sharp aroma, countersunk, smooth and full to paladar, of color amber or gold, with acquired alcoholic strength between 16-22o. Aged during at least two years, by the system of ‘criaderas y soleras’, in oak container of maximum capacity of 1 000 l.
  • Cream: Liqueur wine of ‘Jerez-Xérès-Sherry’, ‘Manzanilla-Sanlúcar de Barrameda’, ‘Montilla-Moriles’, ‘Málaga’ and ‘Condado de Huelva’ with at least 60 g/l of reducing matters of color of amber to mahogany. Aged during at least two years, by the system of ‘criaderas y soleras’ or by the one of ‘añadas’, in oak container.
  • Criadera: Liqueur wine of ‘Jerez-Xérès-Sherry’, ‘Manzanilla-Sanlúcar de Barrameda’, ‘Montilla-Moriles’, ‘Málaga’ and ‘Condado de Huelva’ which are aged by the system of ‘criaderas y soleras’, that is traditional in its zone
  • Criaderas y Soleras: Liqueur wine of ‘Jerez-Xérès-Sherry’, ‘Manzanilla-Sanlúcar de Barrameda’, ‘Montilla-Moriles’, ‘Málaga’ and ‘Condado de Huelva’, that uses scales of generally placed boots of oak superposed, and called ‘criaderas’, in which the wine of the year gets up on the superior scale of the system and is crossing the different scales or ‘criaderas’ by partial and successive transferences, in the course of a long period, until reaching the last scale or ‘solera’, where it concludes the aging process.
  • Fino: Liqueur wine (vino generoso) of ‘Jerez-Xérès-Sherry’ and ‘Manzanilla Sanlúcar de Barrameda’, ‘Montilla Moriles’ PDO with the following qualities: straw-coloured, dry, slightly bitter, slight and fragant to the palate. Aged in ‘flor’ during at least two years, by the system of ‘criaderas y soleras’, in oak container of maximum capacity of 1 000 l.
  • Palo Cortado: Liqueur wine (vino generoso) of ‘Jerez-Xérès-Sherry’ and ‘Manzanilla Sanlúcar de Barrameda’, ‘Montilla Moriles’ whose organoleptic characteristics consists of the aroma of an amontillado and palate and colour similar to those of an oloroso, and with an acquired alcoholic strength between 16 and 22 percent. Aged in two phases: the first biological, under a film of ‘flor’, and the second oxidative.
  • Solera: Liqueur wine of ‘Jerez-Xérès-Sherry’, ‘Manzanilla-Sanlúcar de Barrameda’, ‘Montilla-Moriles’, ‘Málaga’ and ‘Condado de Huelva’ aged by the system of ‘criaderas y soleras’.

What is “criaderas y soleras” system for aging?

The system is far better described on many sites that describe the Oloroso production.In short the process is explained in the picture below as found on this site: http://holafoodie.com/a-beginners-guide-to-sherry/
The process of Sherry’s mentions things like “Flor”, extracting 1/3 of the content of the “Bottom” barrel and adding from the layer of barrels above, etc, etc.When are “Sherry” barrels sold to “Whisky” makers?

This is one interesting question to ask. While browsing websites I found a lot of of influences that make the term “Sherry Butt” seem totally unpredictable. Why do I say this?

At some point in time regulations changed from “Oloroso” Sherry being both Sweet (actual sugar content) and Dry, to only Dry. Dry meaning no to a very small sugar level allowed in a “Oloroso” Sherry.

At some point in time “Transport” barrels for transporting “Oloroso” Sherry were banned from use. Meaning that, these transport barrels could no longer be sold to Whisky makers as “Sherry” butts. See: https://www.quora.com/When-whiskey-is-aged-in-casks-previously-used-for-sherry-or-wine-what-effect-does-it-have-on-the-taste-of-the-whiskey

The time Oloroso barrels spend in the Solera system can be as little as 2 (legal minimum) to as much as 100 years depending on the economic choices made by the Sherry maker to replace or reuse the barrel.

Just like bourbon barrels Spannish Coopers tend to use more and more American Oak for the production of butts for the production of Oloroso, since American oak has grown more strait and therefore the level of waste material left at the cutting process of staves is less compared to more cutting losses seen in Europan Oak. The more level climat conditions in the USA areas of production also ensure a more stable wood production quality compared to the high climate differences all over Europe. These last statements are not based on Science studies, but on a combination of barrel makers technical documents and my own engineering know how of production processes.

This all add up to just about nothing you can conclude when whisky makers say they used “Oloroso Sherry” butts, unless you know:

  • when the barrel was produced,
  • under which version of the “Sherry” laws production took place, (how old is the barrel)
  • from what kind of wood the barrel was produced,
  • how long it spend in the Soleras system (if at all in case of transport barrels, which are now no longer allowed),
  • in what level of the criaderas system it spend its days. Meaning was is filled with new spirit at each step or was it on the last step constantly containing the oldest Oloroso,
  • if the barrel contained “flor” or not. Meaning did it actually contain Oloroso, or one of the other legal versions of Sherry,
  • what preparation the cooper use for charring, toasting before putting the barrel in the production of Oloroso.
  • if the whisky maker re-toast the barrel after receiving is from the Sherry maker,
  • if sugar was added to the barrel to produce the “United Kingdom” version of “Oloroso” that was ones legal,
  • if the whisky maker buys custom sherried barrels just for whisky making.
Depending on the insights to all, and more, of these influences I will try to figure out if there is a set of influences on smell and taste that is a constant.

One thing I am “sure” about is that PX is as sweet from sugar (not vanillin / cocos etc) as it can get! I am sure some of these sugars survive the cleaning processes (if applied) before the barrels are filled with whisky, but since sugars desolve in water, it will most likely only be the sugars left in the wood, if any, that gets transferred/devolved/combined into the whisky.

To help understand the barrels used for whisky a Sherry site has given information which is insightful. See http://www.sherry.wine/media-trade/news/sherry-butts-and-scotch-whisky


I come to, as a personal insight, the observation that there is no one answer to “What is a Sherry But?” Since there seem to be to many variables to give only one answer! As a Whisky drinker we need to be informed by the distiller or blender which type of casks were used holding which content.

If I could make a shortlist of what I would want to know about the “Sherry” and the Cask used to finish or mature a whisky I would say:

  • Type of oak,
  • Type of charr / toast,
  • Type of barrel,
  • Type of “Sherry”,
  • Length of time the “Sherry” was in the barrel,
  • The way the barrel was cleaned before putting the Whisky in,
  • The time the whisky spend in the barrel,
  • How many times the barrel was refilled.

I have made the things that are “unique” for the Sherry influence Italic, since the other information is what whisky drinker are already interested in and are (to some level) aware of the influences on taste and smell. This also means that the first 3 bullets in the list are, or could have, the same influence on the final result of the taste and smell independent of the “Sherry” influences.

I will go into that last observation in a later blog by seeing if “first use” American Oak, which we normally associate with Bourbon, somehow could have similar effects on a “Sherry” matured Whisky.