Birectifier Analysis of Rivers Grenada Rum

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This case study was made possible by an incredible blog friend who donated the bottle because it is not distributed on my side of the pandemic. The individual was curious why this rum is just so fun to drink yet not exactly “good” within the criteria of conventional luxury spirits. Why is it so smooth relative to it’s 69% ABV? Why does it win the intermediate to advanced drinker over so easily?

Of course we are talking about the Rivers rum from the River Antoine estate in Grenada which is new to the American market. There are fascinating articles about this distillery which show just how locked in time production is relative to just about everyone else in the world that modernized. It is as charming as the most rustic producer of Cape Verdean grogues or Haitian clairins, but maybe even more so because the scale is a bit grander and the water wheel is so amazing and possibly because of those double retort pot stills. It tells a story like few other rums, and from what I gather, you can make a pilgrimage to see it all.

Rivers becomes a little challenging to compare to other similarly produced spirits because the ABV is so high but you immediately get a whiff of that vesouté aroma associated with unclarified cane juice. Vesouté is a French term for the raw greenness associated with fresh cane. In some cane juice rums it is a dominant characteristic. Some dislike the aroma, while others like myself particularly enjoy it and consider it wonderful in cocktails. Cape Verdean grogues may be the proto-type for vesouté. Rivers may illustrate an intermediate position described by Arroyo where the cane juice is pasteurized but not clarified. Arroyo gives us a description that intrigues:

(2) The rums obtained from pasteurized sugar cane juices, but not clarified, occupy an intermediate position with respect to the quality of the aromatic gama. Their aroma is more uniform, stable, suave and delicate. It possesses a more harmonious blend of the different components. Complexity of aroma may be present, but it is stable; and presents a single aromatic effect.

Here, Arroyo is describing rums from his own projects and not exactly rums from the market like Rivers, but parts still resonate. If you scroll down to my notes from tasting the fractions, I found a complexity of aroma in fraction 5 with mysterious persistence but my theory is that all the headiness of ethyl acetate prevents the perception of a “single aromatic effect”. Cognac producers do not like that ethyl acetate headiness and consider it a flaw. It sort of spoils the view of high value aroma. Rum consumers in local markets have come to enjoy it and I always say “there is nothing finer than rum as we make it”.

What would this spirit be like to taste with a little less ethyl acetate? Do those specific esters obscure low end power and persistence that we view unobstructed in fraction 5? It is a thought that could become an opinion. After the tasting, I married the remainders of the fractions and only half of fraction 1 which contains the majority of the ethyl acetate. In this micro vatting, I feel like I noticed a little more radiant persistence. I then took this vatting and ran it through my hot water dilution test; I smelt raisin of all things. The hot version is quite good.

The fractions were interesting and defied some predictions. Working backwards, there was less volatile acid in the last fractions than I expected for a low ABV open culture ferment and double retort distillation. Second, there was no tufo aroma. Even with direct fire heated stills they avoid the cooked lees aroma that some producers fear. Could any of this have to do withe the nature of the ferments being significantly backslopped to start the next batch? Far less lees may enter the pot than other pot distilled spirits. The fifth fraction which holds the high value aroma was giving me vinous thoughts and it didn’t seem too obviously “rum” to me. It had a glorious estery quality. I hoped in the fourth fraction it may be obvious if the ferment was a below average fusel oil producer which is attributed to fission yeasts but nothing was too obvious. My guess is budding yeast but that is at odds with all the acetic acid that goes on to become ethyl acetate. Perhaps their ferments are at an intermediate state (1.0-2.0 g/L VA)? The ethyl acetate was pretty major, making you wonder what it took to get there. Do they add any deliberate vinegar? Do their open vats undergo any acetification from acetobacter? Does another bacteria produce the acetic acid?

If we offered the producers at Rivers any ideas what would they be? We can’t really propose anything that may spoil their heritage identity. My thought is that it may be cool if they explored a few lost historic ideas that no one else wants to tackle despite rabid consumer interest. The first is making rum from pineapple disease damaged canes and my understanding is that the phenomenon occurs in Grenada and has been observed happening in a predictable site by farmers at Renegade. The mold is supposed to be aroma beneficial for certain cane species and can generate a pineapple aroma. At one point in time it was prized by buyers in Europe.

Another idea may be introducing aroma beneficial mildew yeasts like Arroyo’s Suaveolens. As a co-ferment, it can produce the ester, ethyl tiglate, which has been observed by both Cory and I. Suaveolens can be isolated from the skin of dragon fruit, no doubt plentiful in Grenada, and we know that Arroyo favored it with cane juice rums and budding yeasts. In theory it may also reduce fusel oil in a budding yeast ferment by consuming certain amino acids and this may have been observed in a recent experimental rum from New Zealand.

Both of these ideas may be introduced without any particular microbiology training for select batches at unique times of the year. They are likely to not damage economy which is already possibly among the very lowest in the industry due to maintaining heritage practices. Rivers is already exciting but a few unique ideas that could broaden appeal are just within their grasp.

Some day I will make the pilgrimage. I’ve had so much fun with this rum and mixed up a few daiquiris. You may not enjoy it as much as me, but you will still find yourself trying to plan a trip to see where it comes from.

 

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Fraction 1: Definitely concentrated to the point of non-culinary aromas. No extra details seem present like possible ethyl formate I had observed recently in rums featuring rampant bacteria.

Fraction 2: Diminutive version of fraction 1 as expected.

Fraction 3: Very neutral as is typical.

Fraction 4: Definite presence of fusel oil. It has an intensity and slight wraith like character. It begs the question, budding yeast or fission yeast?

Fraction 5: Visually, slightly cloudy. Significant insoluble droplets all over the surface. Gloriously estery with remarkable persistence. No obvious rum oil character. Not especially acrid on the palate. This seems to have a lot of persistence relative to other characteristics while not being an obvious positive for rum oil. Sometimes when smelling this I had vinous thoughts. Was this rum or believe it or not, could this be brandy?

Fraction 6: Very much like fractions 7 and 8, but with an extra faint animalic aroma, that doesn’t seem like rum oil. Possibly an acid like propionic?

Fraction 7: Very much like fraction 8.

Fraction 8: Slight aroma, but nothing to intense. Slight gustatory acidity, but nothing too high.

Stillage: