It’s #FibFriday! And Fib of the Week #7 is – “the darker the dram, the better.”. Now, we’re not going to fault you for loving a great big sherry bomb - when we’re in the mood, we do too. But this is going to be a deep dive on colour, flavour and maturation. First and foremost, it’s important to be aware that those compounds which affect colour are largely absorbed into the whisky very quickly, within the first 6 to 9 months of maturation, and colour change is considerably slower after that. Similarly, coloration rather than flavonols can leach out of a cask very quickly - it’s why refill casks even from sherry produce so much less colour, but still might give you an incredible taste. It’s also worth noting that to get a consistent product year on year, whisky producers are allowed to add allegedly flavour neutral spirit caramel or caramel colouring to spirit - E150a - exactly the same additive that you find in Coca-Cola to give it its colouring. And they think you want a really dark sherry bomb, so some perhaps slightly less scrupulous companies will also enhance the colour to increase your expectations. Indeed, we’ve heard, but not seen, ambassadors actually bringing an unlabelled bottle of cola to a tasting as a “special dram” to try to catch people out and educate them about caramel colouring, which sounds a lot of fun to witness during an event. Apparently, some folks even try it and pretend it’s great, so much do they believe everyone believes darker means better. Until they are let in on the joke.
Personally, we agree and understand that there is a place in the industry for E150a, but only among the big producers - you always get a few ignorant consumers who will see a slight colour change in their dram from one year to the next and will think there’s something wrong with it, when the whisky is still exactly the same brilliance that they have been buying for years. Is it slightly dishonest to add colouring? Yes. But we can understand it. Among small producers or those who care about transparency, however, there should be no place for caramel colouring, and it is certainly something that we at Fib Whisky never intend to use.
People naturally associate a darker or stronger colour with a highly active cask and better aged whisky. Accepting of course that bourbon casks will produce golden tones, oloroso and PX sherry dark browns, and port or wine casks something of a red tinge. But the general presumption is often - the more colour, the better. While not entirely wrong, this is a misapprehension on the part of many whisky fans, including some ambassadors. The better ones know, though, that really, just looking at the dram only helps you get some expectations towards what sort of barrel it might have been in. Sure, you can swirl it to see the oils and get an idea of viscosity and likely mouth feel, but sight alone is going to tell you very little about the flavours. We once saw an excellent 19 year old Caol Ila from SMWS that had been filled into sherry butts. The whisky was great, maybe not quite a sherry bomb, but still great. Yet it was pale as water.
When dealing with single cask whisky, it’s important to remember that each barrel is a unique, natural product. Maturation is also a slow and complex process, which is only partly understood. Certain compounds are obviously alcohol soluble, which go into your dram direct; others are created by reactions between chemical components of the cask and the spirit itself; and others simply rely on the fact that the spirit can breathe, leading to oxidation reactions between the air and chemical components of the whisky. Any residue from what the cask has previously held will of course be dissolved and/or react with the spirit quite quickly, hence the faster colour change in a lot of cases. But the really important reactions that make an aged whisky so much less harsh than new-make spirit, and those that add other flavours, take a lot longer. The charcoal layer on the inside of the recharred cask is thought to have some reactions with the spirit to remove or at least reduce unwanted sulphur compounds, and these reactions may happen quite quickly, but the vast majority of sulphur compounds are thought to leave the cask over years predominantly by simple evaporation. This is why older whisky is generally considered to be more smooth on the palate, and why even a well coloured young whisky might still be a little harsh. Similarly, ethyl acetate and acetaldehyde are two flavonols known for their particularly fruity notes - the former, for example, is the most common ester (fruity chemicals) in wine. Levels of both of these chemicals are greatly enhanced by maturation. Yet they are not predominantly absorbed from the wood but instead thought to be mainly formed by oxidative reactions with ethanol. This process takes time, and has little bearing on the coloration of a dram.
You might presume so far that coloration mainly comes from the absorption of chemicals on the inside layer of the cask, for example tannins and other compounds. These compounds on the surface provide colour, true, but not much of the flavour. The charcoal on the inside of charred casks is only thought to catalyse ethanol oxidation to ethyl acetate and acetaldehyde as well as provide minimal filtration of sulphur compounds. It does not itself get absorbed or effect the colour of your whisky, nor are all casks charred anyway. So too with dissolvable lignin compounds and their interactions with the spirit - dissolvable vanillin, for example, is again seriously enhanced by char and re-char treatments on the cask as lignin is degraded to vanillin up to a depth of 6 mm, but again it takes spirit time to soak and absorb to this this level, and more time to then extract the flavour compounds. As anyone who knows vanilla anyway will be able to tell you, this is also not going to have an effect on your colour. But it is an important flavour component for many whiskies, extracted from the wood, and at a rate very different from coloration. Other important processes include esterification, in which non-volatile dicarboxylic acids are absorbed and then catalysed by the greater acidity of the spirit to form fruity compounds, and so too some phenols and phenolic compounds are absorbed through the three processes of esterification, extraction, and oxidation, many of which happen slowly and few of which have any strong bearing on colour.
This list might seem daunting. And I’m not going to lie - wood and other whisky chemistry is certainly fascinating, but it’s also terrifyingly complex to study, especially coming from an Arts or a layman’s background as I did. Some of it is still confusing and I need to refer to my notes and books. But what this all goes to show is that there are very many flavour reactions that take time and patience, completely independent of the usually relatively fast taking on of colour. Each cask is a natural product, and while some might be abundant and very active in terms of certain chemicals, they might be lacking in others. A cask that provides a lot of colour quickly might provide very little flavour even after quite a long time in barrel. And a cask might have huge amounts of colour after only a couple of years, but still need many more, possibly even decades, for all the exciting oxidative and esterification reactions to take place that will develop a whisky to its pinnacle of flavour before bottling.
We enjoy holding a beautiful whisky up to the light as much as anyone, the chiaroscuro interplay through the glass and spirit. But we also know that colour isn’t everything, chemically as well as in terms of our senses. So pretty as it is, we would always recommend putting very little weight on colour. Instead, enjoy your dram - a lot has come together to make those flavours, and a lot of that has bugger all to do with how it looks. So sip and enjoy. Slàinte! 🥃