The Rum University
Rum Lab: Should I warm up my Rum?
The Rum University answers the question about "Should I warm up my Rum?" in the "Rum Lab" section of the 2014 December issue of "Got Rum?" magazine.
Q: Should I warm up my rum? Will I enjoy it more or less if I do?
A: It depends on what type of rum you have in your snifter and to what temperature you are heating it up.
To really understand the complexity of the answer, simply think about the principles of distillation. When distilling, heat is applied to a water-alcohol mixture until the alcohol begins to evaporate. The vapor will have a higher alcohol concentration than the liquid from which it is evaporating, which means that the more alcohol evaporates, the less alcohol (by volume) will remain in the snifter.
Now think about the fact that rum is comprised of different types of alcohols, each with a distinct boiling temperature (aldehydes, esters, methanol, ethanol and higher alcohols). As you heat up your rum, the most volatile alcohols will begin to evaporate first, which is good if you want to increase their concentration in the rum’s volatilized aroma, but if they become volatile that means they won’t be in the liquid rum anymore. If you continue heating up the snifter until you reach the boiling temperature of the least volatile component, you will end up having a snifter with mainly water, tannins and other non-volatile components.
So, if your rum bottle is particularly cold and you don’t find it as aromatic as you are used to, you can slowly warm it up to room temperature. You can also hold the snifter by cupping your hand and enveloping the glass bowl with the palm of your hand, slowly bringing the rum close to your body’s temperature. Either one of these approaches will work fine in helping the rum’s aromas come forth. You can also use a candle, as shown to the left, just make sure you frequently swirl the rum around and that you stop when it reaches a temperature at or slightly above your body’s own.
Warming up a white, highly neutral rum will produce very different results from heating up a heavy, cachaca- like spirit. In the former case, the aromas released will be mainly those of ethanol, and the remaining liquid will be almost the same as the original, with the exception of the alcohol strength, which will be lower the longer the snifter is heated. In the latter case, the aromas released will be mainly those from aldehydes and esters (fruity), while the remaining rum will have an increasing proportion of higher alcohols and a lower ABV as the heating time goes up.
Photo Credit: Engravable snifter warming set from www.HomeWetBar.com