The evolution of rum styles

Rum enthusiasts know all about the enormous diversity of rum flavors, especially when compared to single-country spirits like bourbon or Scotch whisky. A fine Cuban rum tastes nothing like a Jamaican overproof rum, nor a vintage rhum agricole. As we learned in our fermentation, distillation, aging, and blending posts, rum distillers have many “knobs” they adjust to craft their specific flavor profile. A Martinique distiller’s settings are different than their Jamaican counterpart’s.

Today’s wide range of rum flavors didn’t spring fully formed during the spirit’s inception four centuries ago. Rather, they emerged over time, influenced by economics, politics, and technology. How did this come to be?

In the Beginning

It’s safe to say that rum distillers in the mid-1600s couldn’t imagine a world where premium bottled rums from around the globe sell for a week’s pay. Making sugar was the prime directive for sugar estates. Distilling a crude spirit from what would otherwise be discarded was a windfall. Early rum was typically given to enslaved workers or sold to the local worker classes. Making a good quality rum by today’s standards was nearly impossible.

Consistent, high-grade molasses, the backbone of today’s rum industry, wasn’t readily available. Distilleries were adjuncts to an estate’s small sugar mill and boiling house. They fermented whatever was available at the moment, be it soured cane juice, left-over boiling house skimmings, and poor grade molasses. The availability of fermentation material varied wildly from day to day, making it difficult to follow any “recipe.”

There was little scientific awareness of yeast and its role in turning sugar into alcohol. Instead, fermentation arose spontaneously from airborne yeast. Whatever yeast strains dominated in a distillery’s locale were what was unwittingly used.

The stills of the era were very crude pot stills. Their simple construction didn’t allow for good separation of desirable and undesirable compounds. Steam heating was years in the future, so wood was burned directly under the stills. This made it difficult to control and maintain the temperature.

Furthermore, there was little thought given to purposefully aging rum. Thirsty locals quickly consumed freshly made rum. By the mid-1700s, exports of rum to Europe or North America started. “Aging” usually lasted no longer than the ocean voyage to its final distillation, in whatever cask was on hand.

In short, early rum making was a chaotic affair. Maximizing alcohol production took precedence over consistency and quality. Rum makers were in no position to formalize a style or flavor profile as we know them today.

The Industrial Revolution

The industrial revolution that transformed the world in the 1800s brought huge efficiencies to sugar and rum. Centralized sugar factories processed the output of many small estates and produced a steady stream of consistent-grade molasses. This allowed rum distillation to transition from a small, single estate affair to modern factories, unconnected to sugar estates in many cases.

Substantial improvements in distillation equipment enabled higher quality rum to be made at a much greater scale. The double retort pot still and continuous column still were far more effective than the crude alembics previously employed. This helped transform rum from a low-end agricultural commodity into a spirit that could compete with whiskey and brandy.

However, these improvements did not take hold everywhere at the same time. Britain’s Caribbean colonies had rum making mostly to themselves during the 1700s and developed a sought-after style. The heavy, pot-distilled rums of Jamaica and Guyana are emblematic of the “British style” of the era.

Meanwhile, Spain and France prevented their Caribbean colonies from distilling and exporting rum for much of the 1700s to shield their powerful homeland wine and brandy industries from competition. In the 1800s, these shackles started to come off; colonies like Martinique, Guadeloupe, Cuba, and Puerto Rico jumped into rum making.

Early on, France and Spain’s colonies had relatively little commercial infrastructure for making rum. Although late to join the game, they started with the latest technologies like continuous distillation. Meanwhile, Britain’s colonies had little incentive to change what worked. At this juncture, we start to see distinct rum styles emerge.

Cane Juice / Agricole

During the Napoleonic wars, Britain’s navy blockaded France, preventing French Caribbean sugar from coming into France. In response, Napoleon encouraged advances in sugar production using European-grown sugar beets. Beet sugar eventually provided strong competition to Caribbean sugarcane, leading to “sugar wars” where countries propped up their sugar industries while seeking to hinder others. Sugar gluts caused prices to drop far enough that many Caribbean sugar estates lost money or closed.

In the 1880s, faced with grim economic prospects, some Martinique and Guadeloupe estates began making rum from sugarcane juice. A hectare of sugarcane can make over five times as much rum using cane juice rather than molasses. Sugarcane had finally become more valuable for rum making than sugar production.

This cane juice rum had a raw, grassy, and vegetal flavor, a very different experience than molasses rum. Mainland France consumers had little taste for it, so its consumption was mostly limited to the islands. At the time, it was known as inhabitant rum and was typically consumed unaged. It wasn’t until the mid-1900s that it was aged in significant quantities and started being exported in significant quantities. These days we know it as rhum agricole.

Aging Forward / “Spanish Heritage”

While heavy-bodied rums dominated early on, by the late 1800s, Cuba’s Facundo Bacardi and others believed there was a market for a lighter, more refined style of rum. They drew inspiration from Spanish wine and brandy maker’s tradition of extensive flavor development during aging. They sought to make rums closer to a smooth, delicate brandy, rather than the heavy, flavor-bombs of Jamaica and elsewhere.

Towards that end, rum makers in Cuba, Puerto Rico, the Dominican Republic, and elsewhere started using short fermentation, distilling to higher strength in column stills, and mastery of the aging and blending process. Carbon filtration to remove unpleasant flavors was another innovation Spanish heritage producers came to rely on.

By the early 1900s, Spanish Heritage rum was on the path to becoming the best-selling style of rum around the globe, and it remains so today.

High Ester / Rum Concentrate

The spirits industry has been no stranger to deception over the centuries. One example is “stretching” a high-quality spirit by blending it with cheaper spirit or neutral alcohol.

In the late 1800s, Germany imposed stiff import taxes on foreign spirits. Since Jamaican rum was quite popular in Germany, German importers began buying the most flavorful Jamaican rums and blending them with locally made neutral spirit, selling the result as Jamaican rum.

The demand for highly flavored Jamaican rum was so great that certain Jamaican distilleries started using special fermentation techniques that greatly accelerated the creation of esters and other flavor compounds. Such rums were not intended for consumers and were only shipped to European blenders. They were known as continental or German rum.

A similar story played out in France, where mainland blenders stretched pungent, molasses-based Martinique and Guadeloupe rums with three or four times the amount of very light spirit. These highly flavorful rums were called grand arôme (“big aroma”). Luckily for today’s rum enthusiasts, an ever-growing cornucopia of these rums can finally be purchased.

Summary

The above barely scratches the surface of how rum styles evolved. But there’s more! Rum continues to evolve today, taking inspiration from other cultures and spirit traditions. While some of us long to try rum from a century ago, when it comes to experiencing rum’s diversity, there’s never been a better time than the present.