Colour of Whisky

The colour of whisky has often been considered a determinant of the age of the whisky. While whisky ranges from a pale yellow to a reddish or darkish brown, the assumption is that the longer a spirit is aged in a cask the darker the whisky will appear. A dark whisky is associated with richness in flavor and complexity, enhanced by plenty of maturity. A light-coloured whisky, on the other hand, is often dismissed as young and immature, lacking a certain complexity. Whether the colour expectation is propagated by industry or perpetuated by an uninformed whisky consumer, the outcome is confusion about value and importance.

The colour of whisky is determined by several factors that include the size and make of the cask, whether the cask is virgin oak or has been toasted or charred. And, which type of cask was used e.g. Bourbon, Sherry or virgin oak for maturing and wine, rum, IPA, Champagne etc. for finishing. 

So why is colour added? The challenge for the distiller is that casks do not produce a consistency in colour as one cask might impart a slightly different hue from another. This could result from how many times the same cask had been used, different types of oak and the climate and temperature of the warehouse to name a few. To ensure consistency of colour, many distilleries compensate the colour inconsistencies by adding caramel colouring.

Caramel colouring is a product of burning sugars like fructose and glucose until they have turned into a dark syrup known as E150a (E stands for European). E150a (sometimes referred to as spirit caramel), unlike E150b (caustic sulfite caramel), E150c (ammonia caramel) or E150d (sulfite-ammonia caramel), is free of harmful chemicals or residue such as sulfates or ammonium and only a relatively small percentage is used for colour.

Most single malts and virtually all blended whiskies are coloured with E150a. The Scotch Whisky Regulations 2009 stipulates that the only ingredients that can be added to the whisky are water and caramel for colouring.

Is caramel colouring harmful, necessary or simply a vanity? Some in the industry claim it is only harmful when it comes to consumer perception. The Scotch whisky industry claims that adding caramel colouring improves the look and, by extension, the value of their whisky. However, distilleries are becoming aware of the importance of public perception and its influences on a new generation of whisky consumer. This is why we see more and more distilleries moving in the direction of ensuring no colour has been added to distinguish themselves from those that still do.

Chill Filtration

When reading the label on some whiskies, there may be a reference to ‘non-chill filtered’. The purpose of chill filtering is to remove naturally occurring fatty acids, proteins and esters that are formed by enzyme reaction of yeast and alcohol during fermentation.

A non-chill filtered whisky that is 46% alcohol by volume (abv) or lower will go cloudy when ice is added or will develop sediment in the bottle when stored in a cool place. However, whiskies with an abv above 46% do not require chill filtration, as the higher alcohol level prevents this cloudiness from occurring. For whiskies bottled at 46 abv or lower, chill filtering eliminates the cloudiness these elements create when the whisky is cooled.

The chill filtration process involves dropping the temperature of the whisky to zero degrees Celsius for single malts (and -4 degrees for blends). Once chilled, the whisky is passed under pressure through a series of tightly knit metallic meshes or paper filters. The filtering process is also designed to remove other impurities from the cask during maturation that may be present.

The subject of chill filtration is an ongoing debate. Like caramel colouring, the main reason to chill filter a whisky is purely cosmetic and is designed to improve the presentation and appearance for the consumer. On one hand, there is the discerning consumer who desires more natural (or organic) products to complement their lifestyle choices. On the other hand, there are those in the industry who believe that consistency of colour and chill filtration assures quality. Arguably, by eliminating esters, fatty acids and other congeners through chill filtration, this influences the aromatic profile as these are the compounds that enhance the richness and complexity of the whisky. For those who would like to see the industry eliminate the cosmetics through colouring and chill filtering – we raise a dram.

Slàinte (Scottish) – Sláinte(Irish)

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