July Edition 2019
Its a drink that conjures up images of sun-kissed Caribbean beaches, fields of sugar cane, and, of course, pirates. It is steeped in history, (both truth and legend!), with deep connections to both fortune and paucity, international trade wars and naval courage. It’s also possibly the only drink that captures the very soul of its place of making, be it the passion of Hemingway’s favourite boltholes in Cuba, or the serenity of colourful ramshackled markets in Guyana’s towns and villages. It also happens to be one of my favourite drinks, but that, dear reader, is neither here nor there.
Rum as we know it, can trace its origins back to the mid 1600’s, where, thanks to the growth of sugar production they needed to find a solution to the huge amount of molasses that was, at the time, a waste by-product from making sugar. That wasn’t a new thing, as civilisations have been making fermented drinks from sugar since the dawn of hangovers... It wasn’t until the development of commercial distilling methods in Europe, did the rum producers of the Caribbean manage to turn what was, to be frank a pretty awful drink, into something that was vaguely palatable. They were after all distilling a waste product, quickly to make money, that was made for indentured servants and slaves. It also had a tendency to catch fire. Which was handy . . .
Quite when distillers began to care more about the quality of their efforts is subject to conjecture, but it’s pretty certain it was down to market economics. The better the drink, the higher the price is a maxim that still holds today, but at the turn of the 17th century, just over 200 gallons of rum were imported into the UK. 100 years later, and more than 2 million gallons were hitting our shores . . . Rum, ladies and gentlemen, had arrived.
Like every other natural product, making good rum consistently needs more than the best technology and a recipe. The process is the same the world over, but as is often the case, the devil is in the detail and a great distiller is able to ensure that despite the inconsistencies in for example the oak barrels used to age the rum, the finished drink is the just as good as the last one.
Every barrel of rum starts with sugar cane, a plant that is pretty basic when it comes to terroir - soil and climate will affect the amount of sugar in the cane but that’s about it. Once the cane has been sampled and the sucrose levels are where they need to be, it’s a race to get the cut canes from the field to the processing mills. The mills chop, crush and grind the cane to remove as much juice as possible. This is then boiled to a syrup, clarified, boiled again under a vacuum and cooled to remove the crystals. This process is repeated until as much sugar has been removed and molasses remains. The distillers take this molasses, (it takes about 12 tonnes of molasses to make 1 gallon of rum!), dilute with water, clarify it further to remove some impurities, and then add the yeast.
Yeast is just as important to rum distillers as it is to brewers, and a significant number of distilleries have their own yeast strains. Similarly, they also need to be aware of the unwanted compounds and volatiles (congeners) that are the by-product of converting sugar to alcohol in order to remove them from the end product. Once the fermentation has finished, taking anywhere between 24 and 240hrs, the wash (fermented sugar solution) is drawn off and sent to the still. The wash is typically between 4% and 9% abv at this point, and contains a large number of different compounds that have slightly different boiling points. Each distiller knows what flavours they need to make their specific rum, and so draw off more or less of these congeners as required.
At this point the distilled rum is crystal clear, and it is the maturation stage that gives dark rum its deep ruby or golden hues. This is done by putting the spirit into oak barrels, typically 1st fill US bourbon barrels made from American white oak but this is not always the case depending on what characteristics are desired. Whatever the wood, barrel-ageing imparts all those vanilla, warming spice and coconut tastes and aromas that we want in a great rum.
If you’ve been lucky enough to go on a tour of a winery, brewery, or distillery, then at some point you will have rested your arm upon, (or stroked without being aware of doing it!), an oak barrel. We love a good oak barrel, something is comforting about its form and texture that just warms the spirit. Rum is the same in that it loves a good oak barrel too!
There are 3 stages to the rum ageing process, all of which start from the charring of the inside of the cask. This charring changes the composition of the wood (both physical and chemical), adding vanillin, caramelising sugars and making all these flavours and tannins available to the rum. It also does something special to the alcohol when a new spirit is added to a cask. The layer of char removes the harsh edge from the alcohol making it smoother and allows little trapped molecules of oxygen to interact with the rum adding flavour. As time progresses, the wood draws in the rum to its fibres, where it takes on both compounds that bring both flavour and colour to the drink. It also starts to evaporate, increasing the proportion of air in the barrel. Wood, char, air all start to work harmoniously together, and it is this holy trinity that a master distiller has to understand and control.
The 2nd stage is ageing. Now, ageing does not always equal maturity. Maturity is a qualitative measure, whereas age is a quantitative one. A 5yr old rum can have the same maturity as a 7yr old depending on the oak and environmental conditions it has been in, just as another 5yr old can taste like a 3yr old and need more time. Geography plays a part here too, as ambient temperatures and humidity levels can speed up or slow down the maturation process, a barrel of spirit aged in the Caribbean for a year would be the same as it spending 3 years in Scotland. Ageing also magnifies the evaporation of the spirit, and distillers in the Caribbean can expect to lose around 6% of the rum to the angels. To combat this, distillers will regularly top up barrels to try and maintain an optimum level of rum.
The 3rd stage in the ageing process is where the rums are blended. The profile of the rum is influenced by the number of times that the barrel has been used, the number of times it has been recharred, and the variety of oak the barrel was made from, and ultimately it is down to the master blender to create, (and repeat!). This is a hugely complicated role, and their ability to blend a consistent rum with a specific flavour time and time again means that you get to enjoy every bottle of your favourite rum.
Rich - The Beer Emporium