The rums known as “grands arôme” in the French tradition, or “high esters” in the English tradition, have become increasingly popular in recent years.
These rums, which have a high content of esters and volatile compounds other than higher ethyl and methyl alcohols, and which for centuries were blended with less aromatic rums to give them a kick, or were used as flavour enhancers in the food industry, are now being bottled separately. However, defining these two categories remains a difficult task.
Three experts, Stephen Shellengerger, Matt Pietrek and Thierry Grondin, will help us to get to the bottom of it.
There isn’t just one way to produce full-flavoured rums and high-ester rums. But there are some broad common themes. The esters and non-alcoholic compounds that are responsible for many of the aromas present in rum are largely produced during fermentation.
Fermentation therefore takes a particularly long time (at least a week) in the production process, more so for the high ester than for the grand arôme. The addition of vinasse (the liquid residue from distillation) during fermentation is another hallmark. The same goes for encouraging the emergence of bacteria to compete with yeast, even though most of the time they are only allowed in very small quantities, or even banned altogether.
It is this competition between yeasts and esters that gives rise to the particularly powerful aromas found in rums with grand arôme and high esters (varnish, perfume, very ripe fruit, olive jar, brine, English sweets, etc.). When we produce rum, we generally try to avoid the appearance of certain aromas generated by the presence of bacteria.
In this case, it’s quite the opposite: we try to encourage their emergence, sometimes by controlling them, sometimes by giving them a free rein. In some cases (notably in Jamaica), a muck pit/dunder is used (a pit in which organic sludge is grown and seeded into the fermentation tank) to multiply bacterial occurrences.
Using a pot still will also preserve more esters and non-alcoholic compounds, as well as the aromas they produce, although it is possible to do this (albeit to a lesser extent) with a single column. As a general rule, high aromas are produced with single columns and high esters with pot stills.
In Martinique and Réunion
According to the French legal definition, “grand arôme” rum must have a minimum content of volatile substances other than ethyl and methyl alcohol equal to or greater than 800 grams per hectolitre of pure alcohol and a minimum content of esters equal to or greater than 500 grams per hectolitre of pure alcohol. Since abandoning traditional molasses rum in favour of agricole rum at the beginning of the 20th century, Martinique has somewhat abandoned this category.
Except, of course, for the Baie du Galion sugar refinery/distillery (in La Trinité), which continues to produce and market its grand arôme, in particular its 60% Latitudes. It is produced from a long fermentation of sugar cane molasses wine, to which vinasse from a previous distillation has been added. Spontaneous yeasts are used.
But Galion is no longer the only French distillery to produce rums with a high ester content. Savana (La Réunion) launched the production of grand arôme (Lontan range) at the end of the 1990s, as well as high ester (Herr range) a little later, and has been very successful in this segment ever since. The company has even innovated by blending its grand arôme with aged molasses rum (Le Must), or by ageing its cuvées.
Jamaica, the promised land
Jamaica is, of course, THE promised land of high esters. Most distilleries produce different types of molasses rum, which are categorised according to their ester content. These categories are called marks.
These marks may be common to several distilleries, or they may be distinct from one another. Jamaican rums can also be categorised as Common Clean (80-150 esters), Plummer (150-200 esters), Wedderbun (200-300 esters) and Flavoured (700-1600 esters). Distilleries such as Long Pond and Hampden are particularly well known for their very heavy, ester-rich rums.
Once again, the way in which a high ester is produced in Jamaica varies from distillery to distillery. Fermentation takes longer than for a grand aroma, often lasting several weeks. Pot stills are also used. Some distilleries use spontaneous yeasts, others use yeasts selected by the distilleries themselves. Vinasse is added, and sometimes a dunder grown in the muck pit.
Rums made from pure cane juice are getting in on the act
But Jamaica, Martinique and Réunion are no longer the only places in the world where rums with a high ester content and volatile substances other than higher ethyl and methyl alcohols are produced. Just take a look at the Plantation range and you’ll discover that they’re also made in St Lucia and Fiji.
In Barbados, Foursquare and WIRD also venture to offer ester-rich rums, as does Mhoba in South Africa (Pot Stilled High Ester 74.4%). Mhoba’s work is interesting in this respect, since these ester-rich rums are pure sugarcane juice, breaking the hegemony of molasses rums. Another example is Guillaume Ferroni’s work with La Dame Jeanne Heavy N°14, a pure cane juice from the Canary Islands.
At our latitudes, more and more French distilleries are using big aromas and high esters as a model for their molasses rums (the Lyon distillery with its rum fermented for 5 months, for example). The ester-laden style is therefore tending to develop and is finding more and more takers. However, it is not for everyone. If we dared to make a comparison, it would be with the peat of Scotch whiskies.
You either like it, or you don’t. But when you like it, you love it. And that sometimes poses a problem, because ester aficionados can get ‘stuck’ in this type of rum and struggle to get out. But to find out more, we’ve asked 3 experts to explain in a little more detail what Gran Aroma and High Ester rums are all about.
Gran Aroma
You’ll sometimes come across the term ‘gran aroma’, particularly on the labels of bottles of traditional Spanish rum. It has nothing to do with the usual definition of a grand aroma or high ester, but simply means that the rum is more aromatic than usual. Often this is because ‘heavy’ rum, or aguardiente, has gone into its composition.