The Cask: The Essence of Oak

Oak. Where would we be today if it weren’t for the mighty Quercus? The world would be a bleak place, I can tell you that much. Why, you ask? Well, if it weren’t for the existence of oak, whisky would not exist! By law, Scotch whisky must be matured in an oak cask for a minimum of three years. The majority of the whiskies we enjoy today, however, are aged much longer than that, often decades. With so much time spent in wood, it comes as no surprise that a great deal of a whisky’s flavor profile can be attributed to the type of cask it’s aged in. The most common types of oak and how can you know what to look for in choosing the whisky that best suits your unique palate? Let’s have a look…

Unlike our native spirit of Bourbon, which must be aged in new American oak casks, Scotch whisky can be aged in any type of cask, new or used, so long as it is made from oak. This lack of restriction means that when it comes to producing Scotch whisky, the different styles and flavors offered by the spirit are endless. Some casks will yield a spirit that is light, floral and fruity, while others are dark, rich, and spicy. The options are plentiful when it comes to developing flavor in Scotch whisky, all thanks to the unique characteristics of each oak cask.

American Oak

There are no less than 600 species of oak but only a few are used for whisky maturation. Step into almost any warehouse in Scotland today and you may be surprised to see the majority of casks made from just one: American white oak. Undoubtedly the most plentiful (and perhaps affordable) type of oak, most of American oak casks are imported from Bourbon distillers in America. That is to say that before they were used to mature Scotch whisky, they were previously used to age Bourbon in the USA.

Whisky aged in American oak tends to fall on the lighter side of the flavor spectrum. Vanilla, honey, citrus, and hint of coconut are just some of many notes you can expect to find in American oak-matured malt whisky. A classical representation of a Scotch whisky matured in American oak is Cask 39.167 ‘A big tropical adventure’ or, if you’re looking to turn up the wood influence to maximum, Cask 105.21 ‘Truly mesmerizing!’ demonstrates how a whisky aged for more than a quarter century can evolve into a deep and complex spirit.

European Oak

While American oak is often used to produce a lighter, fruitier style of Scotch, whisky matured in European oak is often darker, richer and far more full-bodied in comparison, making for the ideal mid-winter dram. This unique flavor profile originates from several sources; the species of wood itself, which is, by nature, more spicy and tannic than American oak, and the prior contents of the cask itself. While American oak is fully charred prior to use, European oak is lightly toasted.

When it comes to Scotch whisky maturation, the majority of European oak casks come from Spain and previously held Oloroso Sherry. The result? Dark fruit, nutmeg, clove and often a hint of eucalyptus make for an intoxicatingly rich style of whisky. So is one type of wood better than the other? Of course not! Of these two types of wood, it is generally accepted that European oak influences whisky to a greater degree than American oak. Whisky enthusiasts often debate the merits of both- some arguing that European oak will often mask the flavor of the spirit beneath it. Personally, I enjoy both styles for different occasions. When I want to enjoy a lighter, more spirit driven experience on a lazy afternoon, I’ll reach for an American-oak matured whisky. When I want a rich and warming dram to carry me into the late hours of a winter’s night, European oak all the way! Finding your own preference is all part of the fun.

How to Enjoy Cask Strength Whisky

True cask strength whisky is bottled straight from the cask. Much of the Scotch whisky today but not all has been diluted and or filtered and some have had some artificial color added prior to bottling. This does not mean they are bad whiskies. But true cask strength whisky is 100% natural and left virtually untouched from the moment it exits the cask to the moment it touches your lips.

The most notable difference with cask strength whisky is to do with its strength. The majority of distilleries will bottle their whisky at a commercial strength of 40-43% ABV, whereas cask strength tends to be around 55-60% ABV depending on the natural evaporation or as we like to call it Angels Share that took place over the course of its maturation.

For new and seasoned whisky drinkers alike, learning to appreciate cask strength whisky can seem to be an intimidating feat. Following is a step by step guide that will get you on your way to mastering and enjoying cask strength whisky and not missing some great whiskies.

Step 1: Choosing the Right Glass

The size and shape of your choice of glass can have a major impact on what you taste you get from your scotch. This is predominately what we taste in our whisky is manifested by what we smell. Choosing the right glass will help ensure you get the most out of your whisky tasting experience. My recommendation is a Glencairn glass. These type of glasses are designed to funnel the spirits aroma’s straight towards your senses with a very minimum dispersion. To pick up the complex flavors and aromas contained in the whisky, that you want to discover & enjoy.

Step 2: Let It Breath

When opening a new bottle of cask strength whisky, pour yourself a healthy dram and let it breathe before drinking it. The general rule of thumb is a minute for every year the whisky has aged in the cask, not sure I entirely agree with this I find it is more trial to fit your individual taste. You may also find that cask strength whisky will taste even better after the first couple days of opening the bottle. (Of course always recork the bottle after every use)

Step 3: Add Water to Taste

There is always a lot of debate out there that Whisky should be drunk neat. This could be the case when the whisky is already diluted down to 40-43% and even then I believe you should add some water after you have tasted. But when it comes to cask strength whisky, the sheer intensity of the alcohol can usually mask the flavors and aromas of the whisky itself. Especially when it comes to ultra-strong whiskies above the 60% range, the high alcohol level can often paralyze the taste buds.

I prefer to take small taste of the neat whisky first to see how my palate reacts to the whisky. If you find that you start blinking or choking up as a result of the whiskies strength, then most likely your mind is spending more time in survival mode than it is in the art of discovering the spirits flavors.

From here I would start adding small amount of room temperature spring water to your whisky swirl it in the glass gently and let it breathe for couple minutes. Smell the aromas and see how it has changed. Taste again and see how it tastes again and if you feel it’s still too strong add little more water, swirl it again let it breath. See if the aromas have changed and taste again Try to make either mental notes or write down what you are sensing, have the aromas and tastes changed, most likely you will find it kind of like a new whisky. Please remember when adding water only add in very small amounts use a pipette if possible, you can always add more but you cannot take it back out.

The goal is to achieve a point where the whisky is still strong on the palate but not so extreme that it’s taking your mind and focus off why you bought the whisky in the first place to appreciate and explore new whiskies. Grow your experience in different whiskies.

Maybe the one you just purchased has no peat in it so that might be a good next experience and a whole new and fun experience. Like most things in life whether its cask strength or regular strength whisky it takes some time and practice which is all part of the fun. Understanding how you enjoy the flavors, aromas and alcohol content you prefer takes time be patient enjoy the journey.