What is rum? Many folks think of rum as a sweet, distilled spirit from the Caribbean used in Tiki cocktails or mixed with cola. The problem with this definition is that (a) most rum isn’t sweet, (b) much is made outside the Caribbean, and (c) although it works well in cocktails, fine rums are often sipped straight like fine whisky.
So what is rum? Let’s use an analogy:
Whiskey is a spirit distilled from fermented grain.
Mezcal is a spirit distilled from fermented agave.
Which brings us to rum:
Rum is a spirit distilled from fermented sugarcane juice.
Sugarcane is a tall, wide, tropical grass. Originally from Asia, it is now grown in nations across the world.
What is rum made from?
The main ingredient is the sugar juice from sugarcane. This could be –
fresh sugarcane juice. In Brazil fresh sugarcane juice is known as garapa or caldo de cana. In Colombia it is known as jugo de caña de azúcar.
or sugar cane syrup (cane juice made more stable for storage)
or molasses.
What is molasses? When making sugar, the sugar cane is crushed; juice is released, then this juice is boiled. Sugar crystals then form when it is cooled; these crystals are removed and sold as sugar. The leftover liquid is molasses – thick, rich, and dark.
Molasses contains many flavorful organic molecules, quite a bit of sugar, and is a good source of vitamin B6 – and minerals such as manganese, magnesium, iron, potassium and calcium.
How is rum made?
We first grow, cut down, and then mash sugarcane.
We add yeast to the resulting liquid and let it ferment. This creates alcohol and a wide variety of organic molecules – esters, ketones, etc. These give rum its characteristics aromas and flavors.
In some places this fermentation is done in large, open air vats. Natural airborne bacteria can enter the mix, creating their own wildly flavorful forms of fermentation as well.
We now put the resulting brew into a still – an apparatus that uses heat to selectively boil the liquid, and then cool the resulting vapor. Over time the still removes most of the water and all of the solid materials; it removes all of the sugars, carbs, proteins, etc. What remains is rum – a high percentage of alcohol, some water, and a variety of flavorful molecules.
There are many types of still; here is one of the classic forms, the pot still:
There are many types of distillation: pot still, column stills, combinations of the two, etc. We can read more at How rum is distilled.
How is rum aged?
It was discovered that rum stored in wooden casks has a change that often results in a highly desired product. Nowadays rum is often aged in ex-bourbon barrels, but it can also be aged in barrels that once held wine. Or, in this case, these barrels from the Privateer Distillery once held Laphroaig Scotch whisky.
I’ve see it spelled rum, rhum and ron, what does this mean?
Do you want fights among rum nerds? Because questions like this is what starts them.
That being said, a historian would tell you that originally there was no meaning to these different spellings. Same for whiskey, by the way: Looking back over the last 400 years there have been many different names for whiskey, right? Uisce, uisge beatha, whisky, and whiskey.
Well, the same is true for rum: In the past different people pronounced it differently, and thus spelled it differently. English speakers eventually settled on spelling it “rum,”, French speakers often used “Rhum,” and Spanish speakers used “Ron.”
In the last century people tried making well-defined categories of rum. They connected certain spellings to certain styles, which is fine if someone wants to do this.
What is Clairin?
This is a Haitian sugarcane spirit made from locally grown wild sugar cane, fermented with local wild yeast, and distilled in a pot still. It is distilled just once. Until recently clairin usually was never bottled, let alone exported to other nations. It was instead poured from large plastic containers. It is a drink for locals, and each Haitian village made its own.
What is Cachaça?
Cachaça is the most popular spirit distilled in Brazil. They produce well over a billion liters a year of it. The word cachaça is a legally protected term. According to Brazilian law, it must contain between 38 and 54 percent alcohol by volume. Some may have added sugar, but only up to six grams per liter. Some cachaça is consumed unaged, while some may be aged for a year or longer.
While much cachaca is not aged, some is aged in barrels, but not ex-bourbon barrels, as many rums are. Instead –
“With cachaça though, indigenous Brazilian hardwoods are also being deployed, creating an entirely unique flavor influence that is not currently found in any other spirits. For instance, there’s the heavy spice influence of Amburana wood, and the nutty-fruity combination offered by Para. Other varieties put to use include Zebrawood, Cabreuva, Balm, and half a dozen more for good measure.” – What’s the Difference Between Cachaça and Rum?
For the history of cachaça we may read You Know Rum—But What Is Cachaça? from Smithsonian magazine.
Are Clairins and Cachaças rums?
There have been somewhat vociferous debates about this!
Why the disagreements? There are two different ways of looking at things – both of which could be seen as valid.
(A) There’s a culture-first perspective: In this point of view, people make decisions on how to classify spirits through the lens of history and local cultures. People looking at this way see sugarcane spirits as the top-level category. Within this category we can define:
* Cachaça – made only in Brazil from fresh sugarcane juice
* Clairin – made only in Haiti from fresh sugarcane juice
* Rum – any distilled spirit made from sugarcane syrup, sugarcane juice, or molasses, that doesn’t include cachaça or clairin. (This would include AOC name-protected agricoles.)
(B) A scientific or biological perspective. In this point of view, people make decisions on how to classify spirits through the lens of taxonomy. People in this camp often use the word “rum” to mean any sugarcane-derived distilled spirits.
In the United States, the TTB (Tax and Trade Bureau) categorizes cachaça and clairins in this way.
What are the different types of rum?
Addressing misconceptions
If you believe liquor store advertising, there are supposedly several types of rum – light, gold, dark, blackstrap, navy, spiced, and overproof. The problem with this classification system is that every one of these categories is nonsense:
Light rums – These are rums sold as mild and easy to drink. But no such thing actually exists – clear and light colored rums exist in an amazing spectrum of flavors, made with different ingredients, in very different styles. Some of these clear rums can be amazingly funly and complex. Many of the common rums sold in the USA as “light rums” sold here were mass-produced on column stills and then charcoal filtered to remove color. Their supposed smoothness often comes from adding sweeteners and thickeners.
Gold rums – These rums are said to be richer in flavor than light rums. They’re not. They’re exactly the same as so-called light rums, just with more added caramel coloring.
Dark rums – These rums are implied to be aged for much longer. But – surprise! – some of these are the same as light or gold rums, just with even more added coloring.
Blackstrap rums – These are often implied to be distilled from blackstrap molasses. But in fact many rums are made from molasses. And some of the so-called blackstrap rums sold in liquor stores are just cheap, light rum with extra added coloring and sweeteners.
Navy rum – Another meaningless category. The name suggests that this was the style of rum once used by the British Navy. But the British Navy used many different types of rums over the years, from many different distillers, from different nations.
Spiced rums – This is just any rum with added spices (and often sugar.)
Richard Seale, of the famed Foursquare distillery, notes that we’d never classify whisky as white, gold, or dark. Color is the least important characteristic of the spirit.
Matt Pietrek has written a great article on the problems with common rum classification schemes, Categorically Flawed.
Classifying rums by flavor
The folks over at the Whiskey Exchange, in the UK, came up with a way to classify rums by flavor.
Light and Uncomplicated
Rums that are lighter in character and don’t have loads of complexity. They are often modernist rums, distilled to high strengths before bottling, either aged or unaged. This is the flavour that has risen to popularity over the past few decades, unintimidating to drinkers unused to intensely flavoured rums and perfect for modern cocktails and mixers.
Herbaceous and Grassy
This camp is mostly filled with sugar-cane juice rums: rhum agricole and its various cousins from around the Caribbean and beyond. It’s not all sugar-cane juice though, with blends and other rums that show a similar character also in the group.
Fruity and Spicy
These are sweet and spicy with a touch of fruitiness. These are mostly aged rums from traditional stills or blends that focus around those flavours, but anything that brings together those characters will feature.
Dry and Spicy
This camp is focused on the flavours of maturation – oaky spices. However, they are very much the drier side of things, without the sticky sweetness and toffee notes you can find in some rums. Often these are aged modernist rums, where the lighter spirit has picked up a lot of cask character, hiding some of its own.
Rich and Treacly
Thick, sweet and sticky: rums that are dark and decadent. These may have high levels of added sugar, have picked up heavier flavours from cask or even have weightiness from how they were distilled, but they all have a big body and rich character in common.
Tropical and Fruity
Often talked about as ‘estery’ rums, these are the spirits that show big fruity flavour, from bananas to mangoes and pineapples. Often found in Jamaica – an island famous for ‘funky’ rums – these have a character all of their own and are a must for rum fans. Fruity rums are also popular in blends, giving a tropical flavour that pulls the resulting releases into this category as well.
To this we may add:
Deeply Hogo funky rums
What distinguishes rums in this category is that they contain a very high amount of certain aromatic esters. This gives them a flavor known as hogo – a word derived from the French term haut goût. The aroma and flavor of hogo is hard to describe to those who haven’t tried it, but one could say that it has elements of rotting fruit and some say gaminess (notes of game meat.)
These notes exist because some rums allow wild bacteria, and not just yeast, to become an essential part of the fermentation process. Another part of the magic is that funky hogo-rich rums are fermented for much longer than traditional rums. Regular rums are fermented for between one to three days, but this category of rum can be fermented for one to three weeks. To learn more see Matt Pietrek’s article, Beyond Jamaican Funk – Next Level Hogo.
And of course
Cachaças – A distinct category of its own.
Clairins – A distinct category of its own.
The chemistry of rum
From the Compound Interest blog we read
“There are a whole range of ester compounds found in rum; they’re often the dominant class of organic compounds found in the spirit. The range of esters adds the fruitiness to rum’s aroma; particularly important contributors are ethyl propanoate which contributes a caramel-like, fruity aroma, and ethyl isobutyrate which has a butterscotch-like aroma. Rum has a higher short-chain carboxylic acid content compared to other spirits, which may also help explain why its ester content is higher than other alcohols.”
For a deeper dive into rum we can read more about –
Why are fine rums not as well known as fine whiskeys?
Fine Caribbean rums that can be enjoyed straight
Thanks for reading! While you are here check out our reviews of bourbon, Scotch, Irish whiskey, Canadian whiskey, ryes, flavored whiskys, and rums. We have articles on science & health, and a plethora of other topics. Learn more about me, Distilled Sunshine.
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