Tasting rum is not the same as trying rum. At least not when reviewing it. And I've found a system that seems to work for me by using basic elements of wine tasting, mixing in a little instinct and some suggestions I've come across, and eventually coming up with a methodical system tailored for rums.
I believe rum to be a varied, complex and flavorful spirit. Since casks that were once used to age other spirits are later used to age and give flavor to rum, it's hard not to think of rum as a barrel's coup de grâce. As such, there are many elements to consider when tasting rum: appearance, aroma, flavor, sweetness, spiciness, complexity, smoothness, bite, body (for more on Rum, visit Rum 101).
Prior to proper tasting, it's important to have a clean palate as it is key to accurate tastings. Coffees, chocolates, and spicy food can particularly interrupt olfactory chemistry and is not recommended before a tasting (or during a tasting for that matter, unless it's part of a mixer trial).
And then comes the fun part...
First I nose the open bottle and get my first impressions of its unpoured contents.
I pour it into a clean tumbler (or sometimes snifter) and sniff again. Like a dog identifying a smell from across the room, the trick to best absorbing and identifying a rum's bouquet is to take quick whiffs. Though smell may be the strongest sense tied to memory, it is our most primitive and least developed: so although a human nose can recognize hundreds of unique smells, the brain has difficulty articulating said smells. As such, it helps to inhale aromas and odors in quick bursts to maximize its impression and retain the brain's focus on the smell. And since the nose fatigues in less than 7 seconds before a break is needed, it's best to identify quickly and provide your olfactory rest between whiffing sessions.
I then take one quick sip, kind of a half-shot. This gets the initial tongue shock out of the way. Alcohol can interfere with taste receptors on the tongue, so this introduces the alcohol to the mouth and gets the taste buds prepped for subsequent sips. I note what I can, but this first taste is only a primer. I then take another sip, this time slowly and with purpose. I give it a quick whoosh in my mouth to allow some evaporation under my nasal cavity in order to better identify aromas and flavors and determine their intensity. The rum's sweetness is judged, as well as its balance according to bitterness, spiciness, acidity, etc.
For me, the key to tasting is first allowing the nuances to present themselves to you, and then actively and methodically looking for and identifying common, known, or hinted flavors. For example, I may taste a general sweetness that possibly hints at fruit. I try to break it down more precisely: is it citrus in origin? Stone fruit? Melon? Berry? Once I feel I am able to confidently identify the family of fruits, I will try, if possible, to identify it further to a specific fruit.
Once these impressions are recorded, I'll take another sip while taking into account the rum's body, giving it time to roll across and around my tongue to test its viscosity, thickness, and weight as well as its texture or mouthfeel. I assess finish and aftertaste, seeing how long the taste persists and how the lingering flavors present themselves.
The rum is then allowed to breathe with a short, purposeful turn of the glass (the vigorous swirling associated with wine is unnecessary). Aeration may stimulate other tastes and aromas. I will also warm the rum with my hand a bit as one would a good brandy or whiskey, giving the rise in temperature an opportunity to release further complexities. I repeat the tasting process again, continuing with small sips.
A small splash of filtered water at room temperature is then sometimes added to tone down the alcohol level and thus allow the palate to enjoy more flavors and aromas.
Then if necessary, and usually after having to pour a little more out of the bottle, I experience the rum with ice. Cooling the rum may actually mute aromas and flavors, but it also tends to tone down the alcohol content, pushing aside some bite and often helping reveal more complexity. For younger rums, I find this - as well as the prior step of adding a small splash of water - to be the most useful and enjoyable steps in the process. And no, not just because I'm half-inebrieated by then.
Mixers and Cocktails
Finally, if appropriate, I'll try the rum with a mixer of some kind. Usually it's Coke (preferably a cola made with sugar cane and not high fructose corn syrup, and rarely Diet Coke or Coke Zero), but ginger ale, lemon-lime soda, club soda, pineapple juice, lime juice, cranberry juice, or orange juice may make an appearance. When applicable, I'll try the rum in standard rum cocktails such as Daiquiris or Mojitos. Also, I'll note how a rum works in tropical drinks (also known as boat or blended drinks). Premium rums will of course seldom be lost in too much mixing - an Old Fashioned cocktail or a few drops of water, club soda or coke and maybe a squeeze of lime will do.
I'll also crack open my humidor on occasion to enjoy a nice cigar with my rum, noting how it handles the smoke and tobacco.
When possible, I'll give the rum a second tasting the following day or two in order to confirm my findings or make new discoveries.