Yeast in Rum (or S. Pombe Revisited)

Following on from the three part collected article titled “Aeneas Coffey, John Dore and Foursquare”, Richard Seale posted an in depth look at “Yeast in Rum” in a 6 part series on his personal page, with his agreement I have again collated them into one single reference article below.

Yeast in Rum (or S. Pombe Revisited)

Part One – Yeast History

Back in October/November 2019, I created a quite a stir with some comments and a very brief post challenging some of the myths being created around the novel sacred cow that is S. Pombe yeast. At Foursquare we carry out natural fermentations (which contain S. Pombe) and having made some ‘high ester’ rums last year, it seems a good moment to make a further comment giving more details on the work of Jamaican chemists Percival H Greg, Charles Allan and S. F. Ashby.

A Little History:

Yeast cells were among the first microbes seen in early microscopes and some of the earliest observations concluded it was produced by fermentation rather than the agent of fermentation. In 1755, Dr. Johnson is his famous dictionary defined ‘yest’ as ‘the foam spume, or flower of beer in fermentation’. See also his cross reference with the definition of ‘barm’.

Lavoisier (1789) investigated wine fermentation by qualitative methods and could not find a role for yeast in the reaction that produced alcohol. However, by this time scientists believed yeast (or ferment as it was called) played a role in starting the process. Berzelius called this catalysis. German Scientist Theodor Schwann identified yeast as a living organism and call it ‘zukerpilz’ – the sugar fungus (or sugar mushroom). His colleague Franz Meyen that provided the modern latin name in 1838 – saccharomyces cerevisiae – literally ‘beer sugar-fungus’ for the species of yeast in common use today (through the use of thousands of strains of the species). Pasteur also supported the idea that fermentation was a biological process, that is a process by living organisms.

Famed German biologist Justus Von Liebig disagreed with this ‘vitalist’ theory arguing that alcoholic fermentation was a purely chemical process – no living organisms were involved – and this led of one of the most famous disputes in Science. Liebig believed the yeast was kind of nitrogenous organic compound which decomposed the sugar and a product was deposited described as an insoluble ferment. This ferment could be used as ‘ferment’ in another sugar solution. Pasteur would eventually settle the debate through a set of brilliant experiments.

Ultimately neither scientist was entirely correct or entirely wrong. Eduard Buchner obtained pure samples of the fluid inside the yeast cell and discovered that the fluid could ferment a sugar solution despite the fact the yeast cell was obviously dead. He realised that fermentation reactions were a chemical process inside the yeast cell by what we know today as collection of enzymes. So alcoholic fermentation is after all a bio-chemical process. Buchner would publish his work in 1897 for which he would be awarded the Nobel Prize.

Pasteur’s work would extend to improving wine making. He observed that soured wine was caused by the presence of lactic acid. He further observed that sour wine contained not only oval yeast cells but small rod shaped bacteria. While alcoholic fermentation occurred via yeast, lactic acid fermentation occurred via bacteria. Pasteur developed the process of heating the wine to a specific temperature for a short time to kill the bacteria a process we know today as ‘pasteurisation’ which would eventually find widespread use in the beer, milk and juice industries.

Danish mycologist Emile Christian Hansen, working at the Carlsberg Laboratory would take yeast understanding a step further. Pasteur had not fully solved the problem of brewing cloudy and off tasting beer despite pitching bacteria free yeast cultures. Pasteur had seen yeast as homogeneous cells, Hansen was the first to isolate different strains/species of saccharomyces yeasts. He discovered that certain strains were directly responsible for the cloudy beer and so by isolating and selecting particular strains for the brewery the problem of cloudy and sour beer could be solved. So now it was necessary to not only eliminate bacteria from beer fermentation but also so called ‘wild yeasts’.

The work of Liebig, Pasteur and Hansen are important to understanding the work of two giants of the Jamaica Rum industry – the planter and distiller Leonard Wray and the chemist Percival H Greg which we will consider in Part two.

 

Part Two – Wray and Greg

Leonard Wray (family to the more familiar J Wray) published his famous treatise in 1848 and his understanding of fermentation was based on the work of Liebig.

For Wray, the nitrogenous matter that would initiate fermentation was already contained in the raw material and so no yeast (or ferment) needed to be added:

“it is seen that molasses and skimmings each contain sugar, gluten, and water; so that fermentation will occur spontaneously in them without the intervention of any foreign substance, such as yeast”

As Lavoisier had quantitatively demonstrated before him, Wray stated the elements of the yeast (the glutenous or albuminous matter) “take no appreciable part in the transposition of the elements of the sugar ; for in the products resulting from the action, we find no component part of this substance”

For Wray, as Lavoisier, the yeast had no part of the final product, for Wray “the peculiar flavour of rum is generally understood to proceed from the resinous, aromatic gum (or essential oil), contained in the rind of the cane”.

Wray relayed an anecdote which marvelously echoes today:

“It is not more than a few days ago, that I was asked by a person why yeast was not used by our sugar planters as ferment instead of dunder ; intimating in very significant terms, that he considered all the West India distillers a very choice pack of fools. Now, this person says that he has been for a long while manager of one of the largest distilleries in the world. He has written a pamphlet on distillation, with a view to enlighten the minds of all distillers, and no doubt fancies himself possessed of all possible knowledge of the subject. And yet this person, who is a clever man, and no doubt very competent to instruct English distillers, does not know what dunder is, or what is its use in the fermentation of wash.”

Wray in his seminal work put his erudite view in the strongest terms, “no foreign agent — such as yeast — is necessary. Nay, further, that such is extremely undesirable ; as it would change altogether the character of the fermentation” (my emphasis).

Wray’s understanding of fermentation was not precisely correct but in practical terms, he was not wrong. Moreover, he was prescient. Everything needed for fermentation was indeed there, no ‘foreign agent’ was needed but the rise of pitched yeast with isolated, sterile yeast strains would forever change the fundamental character of rum fermentation not just in Jamaica but in every rum producing country. Today, just a handful of rum distilleries operate under Wray’s philosophy, almost all of them in Jamaica, most notably the Hampden and Long Pond Estates in Trelawny.

The first serious challenge to this approach would come from Percival H. Greg. Greg was the first chemist to isolate individual strains of yeast as found in Jamaica distilleries. Greg was strongly influenced by the work of Emile Hansen and travelled to Copenhagen to work at the Carlsberg laboratory under the supervision of Hansen’s colleague, Prof. Alfred Jorgensen. At the Carlsberg Lab, he conducted a series of experiments on molasses and dunder sent over from Jamaica. Greg became convinced of the merits of isolating, selecting and pitching a strain of yeast as was now becoming practice in breweries and distilleries around the world. Writing in ‘The Sugar Cane’ in 1893, Greg advocated:

“Not only must we do away with spontaneous fermentation by using a ‘pitching’ yeast, as brewers term it, i.e. adding some previously prepared yeast to set our vats in fermentation at once, but I strongly recommend the selection and cultivation of a suitable type of yeast in a state of absolute purity”

Greg was not alone in his ideas. Pairault (1903) and Kayser (1913) also suggested that starter culture yeasts for rum production should be selected. Both Pairault (1903) and Kayser (1913) recognized that bacteria were also endemic to rum but in their view they negatively impacted on production efficiency and quality. Fahrasmane (2002) reported that “after 1918, some distillers in the French West Indies who wanted to increase the alcoholic yield decided to put into practice the advice of Pairault and Kayser on pure fermentations. Although the result was an increase in yields, the quality of these products evidently fell because of their increased chemical neutrality”.

The star of the show of the strains tested by Greg in Copenhagen was a fission yeast, aka Schizzosaccharomyces Pombe (S. Pombe) which he dubbed No. 18. It is this earliest work in yeast selection that still resonates today in those who believe this type of yeast to be the holy grail in the search for the best Jamaica rum. Following Pasteur and Hansen, Greg at this time saw bacteria as only a source of potential disaster.

Enter Charles Allan who took entirely the opposite view. We will examine that in Part three.

 

Part Three – Allan and Ashby

In 1903, the Jamaica Board of Agriculture decided to hire a specialist Fermentation chemist as well as to set up a sugar laboratory, a fermentation laboratory and an experimental distillery with a 50 gallon still with a “telescopic head” and detachable retorts. The purpose was to study rum making with a view to improving yields, quality and studying the types of yeast involved. Charles Allan would be given a three year contract for the role under the supervision of legendary ‘Island Chemist’, H H Cousins. In 1905, it was Allan who supervised the implementation of Cousins High Ether Process at a specially built plant at Hampden Estate. A process still in use today.

Allan was able to show that the “flavour” of Jamaican rum was not the result of alcoholic fermentation by yeasts but due to acidic fermentations by bacteria.

“The point I wish to emphasize at present is that the value of rum depends mainly on the secondary products [the congeners] it contains. I will show you by means of experiments in the laboratory that cane juice or molasses fermented by yeasts alone produce but very little of the secondary products. These, therefore, must be formed by other organisms, chiefly bacteria which swarm in the washes of Jamaican distilleries”

Allan contrasted the modern approach of breweries of his era with the approach needed by the Jamaican distiller to make the best rum.

“In the most up-to-date breweries now not only are all bacteria excluded but yeast which has been carefully cultivated from selected seed are only used. The effect of this on the article produced was to alter to an appreciable extent its flavour but it ensured its stability in character and in a short time the newly acquired flavour got to be appreciated. In the case of Jamaica rum however we have an article of a very different nature to deal with. The flavour is of a very pronounced character and is one of its chief assets. The flavour of beer is very delicate and is produced by the yeast itself whereas I am of title opinion that the yeasts contribute but a small amount of the flavour of rum”

Allan’s successor at the Jamaica Government Laboratory was S. F. Ashby. Ashby had also studied yeasts at Copenhagen and was the Bacteriologist at famous Rothamsted Experimental Station in the UK before arriving in Jamaica in November of 1905.

He set about to explore further the contribution of yeast to Jamaica rum. He set up ten experiments with sterile washes seeded with strains of the fabled S. Pombe, selected due to the earlier work of Greg. The results were a disaster.

“The rum could hardly be called by that name, and it showed the same character for all ten yeasts; in no case was any characteristic flavour produced”.

Ashby continued with another series of experiments where acid was added to the otherwise sterile washes seeded again with S. Pombe.

“The conclusion to be drawn from these experiments is that, whereas none of the fission yeast isolated from the estate washes was able to produce flavour on its own account, the top yeast owing to its slower fermentation admitted a greater amount of chemical ether production in a wash originally high in volatile acids. The latter result is in accordance with distillers’ experience as they consider that a wash showing a strong fatty head due to the top fermenting fission yeast yields the best flavoured rum.”

Ashby set up further experiments again with added acids but this time observing the behaviour of each species of yeast (S. Cerevisiae and S. Pombe) with each type of acid (acetic, lactic, butyric) these being the common acids in distillery washes (produced primarily by bacteria).

“The ability of the budding type [S. Cervisiae] to multiply and ferment more rapidly from the outset in the weaker acid liquors, like cane juice washes and fresh skimmings, explains why this is the only kind found in such liquor the acidity of which is generally under 0.5%. In the usual estate washes containing dunder, molasses, acid skimmings, and frequently specially added acid, [this would be known as ‘flavour’ made in a muck pit or trash cistern ] the budding yeast [S. Cerevisiae] is largely suppressed, but the more slowly developing and very acid resistant fission type [S. Pombe] takes possession, and is practically the only form found in washes the acidity of which is 1.0% and over”.

Ashby demonstrated in experimental work that the remarkable qualities of S. Pombe are not in its ability to produce flavour of its own account but its ability to make alcohol in washes that are set up to make the characteristic flavour of high ester Jamaica Rum. Its slow rate of fermentation is also particularly important in allowing these characteristic flavours to be developed rather than rapidly consuming the available nutrients and producing the sterilising alcohol which would retard their development.

After his contact was concluded, Ashby would continue to have an illustrious career, he would also work in Trinidad before culminating his career as the mycologist at the Imperial Mycology Institute located at the Royal Botanic Gardens in Kew.

In fact Greg too in his work had also demonstrated that S. Pombe was no panacea – a simple trial of No. 18 in the absence of dunder produced no flavour. In his final paper on Rum aroma published in 1895, Greg concluded:

“If one may be allowed to theorize a little, there seems sufficient grounds for concluding, from the results which I have up to now attained, that though the aroma of rum is in the first instance derived from the soil, that this influence is chiefly potential not actual; that it is latent , dormant , and only brought into existence during the process of manufacture”.

Greg was back to Wray even before the arrival of Allan and Ashby.

So what does yeast contribute? We look at that in Part four.

 

Part Four – Yeast Flavour

Yeast is a bit of sacred cow itself in distilling, not least of all the current fad of S. Pombe. The primary mission in this series of posts is to explain the role of yeast in the context of traditional Jamaica high ester rum, not to diminish its broader importance. The role of yeast in any spirit category is wholly dependent on the culture in which that spirit is made. Yeasts and bacteria are the organisms directly responsible to creating flavour in alcoholic fermentations. Allan summarised well the challenge of striking the balance between the two:

“In making rum the first consideration is to produce alcohol. This can be done by encouraging the development of yeasts but in so doing you are discouraging the growth of bacteria and again if you encourage the development of bacteria you are setting up conditions which are against the interests of the yeasts. You must choose a middle course and it is just here where our greatest difficulty arises.”

Fortunately yeast does not only make alcohol but flavour congeners are produced as by products of yeast metabolism. These include higher alcohols (propanol, amyl alcohol etc), acids (acetic, lactic etc) esters (ethyl acetate), acetaldehyde and diacetyl. Further esters are formed by combining the produced acids with alcohol. Nykanan and Suomalainen (1983) listed 400 flavour metabolites of yeast fermentation. Of course only the volatile ones that pass over into the distilled spirit would be relevant for rum or whisky.

Yeasts are not a typical fungus in that their spores do not migrate by air currents. They are thought to be carried in the stomachs of insects. Recent research in Belgium – Christiaens et al 2014 – showed that fruit flies could use the aromatic odour produced by yeast to find fruit. The yeast helps the fruit fly find the fruit and the fruit fly helps the yeast move around. In short, fruit flies defecate yeast, and yeasts defecate alcohol (and some nice smelling bits).

Yeast autolysis is the degradation (by its own enzymes) of the cell wall and its contents following the death of the yeast cell. Yeast death is not a function of age but of how many times the cell has reproduced. This autolysate or ‘yeast extract’ notwithstanding its foremost importance to making marmite plays an important role in flavour development in fermented wines and spirits. Autolysis is strongly influenced by acidity and ethanol both of which are abundant at the end of fermentation. Several flavour compounds are released during autolysis including fatty acids (which will make esters and aldehydes) and heavy esters (e.g iso amyl caproate), terpenes (thought to be the constituent of what famed Puerto Rican chemist Arroyo called ‘rum oil’) and higher alcohols such as iso amyl alcohol.

Yeast autolysis is a very important part of the champagne method where the where the wine is kept in contact with the yeast autolysate in the bottle. It is also known as the ‘sur-lie’ method for making white burgundy. The autolysate is also a source of nutrients for bacteria. Greg, in one of his caveats for using yeast No. 18 advised it was important that the ‘dead wash’ sit for a couple of days before distillation. Ashby noted that S. Pombe produced far more autolysate than S. Cerevisiae. This is because of the double wall thickness of the fission yeast. This extra biomass is mainly polysaccharides. It does not contribute to flavour in distilled spirits save for providing nutrients to bacteria.

So just how did Jamaicans strike the balance described by Allan. That is for part five.

(pictured – A schematic overview of the main metabolic routes inside the yeast cell contributing to the synthesis of higher alcohols and esters when inserted in the fermenting medium)

 

Part Five – Striking the Balance

The addition of dunder (and its analogs of sour mash in bourbon or backset in whisky) as practised by all rum makers in the West Indies from the 17th century was precisely to set the balance described by Allan. By adding the acidic dunder at the outset, the acidity of the wash was increased to bring it into a zone that was still tolerable for yeast but inhibitory to bacteria. Favouring yeast was paramount because making alcohol is paramount. No point having bacteria produced flavour if they have gobbled up all the sugar and there is little or no alcohol. Many distillers today still adjust acidity in their pitched yeast fermentations by the addition of sulphuric or other acids.

Jamaica (and to a limited extent Barbados) would dimensionalize the molasses/juice/water formula of Wray by the addition of soured juice skimmings and something literally called ‘flavour’. Flavour was produced by a sort of parallel bacterial ferment using cane materials in a ‘trash cistern’ or ‘muck pit’. Each high ester rum making estate developed their own formula and method for ‘flavour’.

It is this use of soured juice and ‘flavour’ that tips the pendulum of aroma development in Jamaica Rum to bacteria over yeast, not that we wish to understate the importance of their symbiotic relationship. The creation and addition of ‘flavour’ in the Jamaican high ester rum making is the cultural equivalent of a bourbon distiller selecting and pitching their own favoured yeast strain. For wine and beer, yeast is king. In Scotch whisky, they do not boil the wort as in beer but rather heat it to 64C for a short time and so some bacteria is inevitably present during fermentation. With the early dominance of pitched yeast, the bacteria, chiefly lactic acid producing bacteria makes its presence felt at the end of fermentation – no role required for S. Pombe. Yeast autolysis would provide the nutrient requirements for the lactic bacteria. Late lactic bacteria is now widely considered to have a positive contribution to the flavour of the whisky (Geddes and Rifkin 1989). So in Scotch whisky, yeast is still king but the pendulum is swung a little in the direction of bacteria.

Today nearly every beer, wine or spirit including much of the rum in Jamaica is now made by pitching selected yeast strains, the practice outlined by Hansen in the late 19th century. The yeasts used are mostly of the saccharomyces type particularly the species saccharomyces cerevisiae for which there are literally thousands of strains. Saccharomyces types have such broad application because it fits the needs of the distiller so well. It is very efficient producing rapid fermentations, dominant (killer strains release a toxin to kill wild yeasts), tolerant of high alcohol content and by species/strain selection it reliably produces the desired flavour.

The yeasts used in whisky industry are mostly S. cerevisiae although various secondary species have been used. Lager yeast is S. pastorianus, ale yeasts include S. cerevisiae and apparently some S.bayanus strains. The wine industry mostly use S. cerevisiae and/or S. bayanus. Some wine makers and craft brewers use non saccharomyces types including Kloeckera, Saccharomycodes, Schizosaccharomyces, Hansenula, Candida, Pichia and Torulopsis. The use of non saccharomyces types is more practical in brewing because they can use a sterile wort. Trying to use non Saccharomyces types in rum is impractical as wild Saccharomyces strains will quickly dominate. Peynaud & Sudrand (1986), Haraldson and Rosen (1984) and Fahrasmane et al (1986) all found that Schizisaccaromyces strains in pure culture produced very few congeners.

In the past, Schizosaccharomyces yeasts were often detected in wines suffering from organoleptic faults through the appearance of sulfidric acid (hydrogen sulphide), acetic acid, acetaldehyde, acetoin and ethyl acetate. Most of these would not necessarily be a fault in rum making. Further research with highly selected strains of S. Pombe showed much better results (for wine) but their attraction for wine making was more related to the ability of this yeast to degrade malic acid rather than any remarkable aromatic profile. It should be noted that Ashby reported the existence of a ‘fruit ether’ yeast of the budding type, that is to say it was not S. Pombe.

It has been suggested in some circles that S. Pombe needs to be “reintroduced” into rum making. It is a ridiculous statement, it never left. S. Pombe plays its usual role at Hampden estate as it has done for over 250 years and S. Pombe can be found wherever rum is made. Several early studies identified S. Pombe in molasses and juice in rum distilleries in the Caribbean. More recently Fahrasmane (1988) found S. Pombe prevalent in Haitain distilleries. Bonilla-Salinas et al (1995) found S. Pombe in Mexican distilleries and Green (2015) found significant counts of S. Pombe yeasts in molasses at Bundaberg in Australia. You can find S. Pombe in our fermentations at Foursquare where their role varies depending on the rum to be produced.

The revised interest and circulation of the papers of Greg, Allan, Ashby et al by bloggers, enthusiasts, distillers and writers is absolutely to be applauded. I cant praise these efforts enough. That this 100 year old work still serves as inspiration to younger craft distillers is a joy to observe. My caution is not to take the work in isolation and consider it hand in hand with later work and the practical operations of West Indian Rum today that has built on and added to that knowledge. That such is not readily available via google should not detract from its value. As Wray warned, do not take the West Indian distillers for a ‘pack of fools’.

We do not need to reintroduce S. Pombe to rum, what we need to do is protect the traditional way in which it is used.

We will consider that in part six.

 

Part Six – The Jamaica GI

The core of traditional Jamaica rum making is the art of using simply sugar cane derivatives, spontaneous fermentation and batch distillation. Distillers were able to improve and innovate without ever breaking these fundamental core principles. In 1893, the year Greg published his first paper, 148 Jamaica distilleries operated this way. By 1948 there were just 25. Today just one distillery owner exclusively practices these methods. Pitched yeast and continuous distillation have changed Jamaica Rum (and Barbados Rum) forever as warned by Wray and J C Nolan (special commissioner to the UK for Jamaica rum) respectively. These two horses have bolted. There is no putting them back. But we can stop here and forever protect these methods.

In 2016, the Jamaican distilleries by unanimous agreement restricted the addition of fermentation agents ( those foreign agents of Wray! ) to yeast and only to yeast of the saccharomyces types. There was no restriction on native yeasts and bacteria proceeding in their normal spontaneous and natural way. How could they? Forced Sterilisation? One-third of the shares in a single Jamaica distillery changed hands in 2017 and since then, that pernicious shareholder has sought to discredit the GI as registered – most wickedly by mischaracterising the GI restriction as “narrowing to one genus of yeast we are wiping out hundreds of years of history of rum making”. Willful ignorance or just ignorance, I let my hopefully now better informed readers be the judge.

The distillery has now demanded through their team of lawyers that the Jamaica IP office unilaterally rewrite the GI to their personal specifications despite the protests of the remaining three distillers. One of my Jamaican colleagues, very high in the industry there, called this “insidious re-colonialization, putting his own selfish needs ahead of the industry and in contravention of the spirit of the GI.” I call someone who acquires a minority interest in a Jamaica distillery in 2017 and who then demands the GI be rewritten to their unilateral specification a megalomaniac.

Among the demanded changes, all designed to render the GI nugatory, is a demand to add other fermenting agents including bacteria. So pitched yeast and now pitched bacteria. A kind of rapid, cheaper ersatz Jamaica rum to be made and sold under a cloud of trite, hyperbolic marketing clichés. Pitched yeast and pitched bacteria take us further away from the true terroir of Jamaica Rum.

I suspect part of the motivation to rewrite the GI is the delusion based on the once again trendy advocation of Greg that magical Jamaica Rum will produced by simply pitching S. Pombe. It takes a high level of Dunning-Kruger type stupidity to think you are going to “innovate” Jamaica Rum by simply changing the brand of added yeast. You need to take West Indian distillers for a ‘pack of fools’ to believe this.

I will let Maggie Campbell, artisan distiller, yeast guru and esteemed colleague have the last word:

“It is wise to remember this is the life’s work and lived experience of these GI supporting Jamaican producers, they are not unwise or foolish, rather they are guardians of their culture and community. No one needs to benevolently jump in and fight to save Jamaican rum from itself, they are protecting it just fine themselves and the GI laws are set up to do just that”.
“If you do not want to participate in the community standards and cultural practices then you do not also get to demand instant access to leverage that community’s and culture’s hard won reputation for excellence.”

 

Again, huge thanks to Richard for allowing me to collate and reproduce the information here

© Steven James, Rum Diaries Blog and Richard Seale. Unauthorized use and/or duplication of this material, both written and photographic without the express and written permission from this blog/sites author and owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Steven James, Richard Seale and Rum Diaries Blog with appropriate and specific direction to the original content.

MHOBA Rum – Pure Single Sugarcane Rum – Part 2

Time for Part 2 in the series of MHOBA Rum reviews but the third part in the full MHOBA series of articles. You can pick up on Part 1 of the reviews here and also read a lot more into MHOBA and the inner workings of what they do here.

You can clearly see in those two articles how much effort goes into the production of the output MHOBA and how much care is taken to prepare the casks for the maturation of MHOBA Rum. This article will feature three of the four matured Rums in the line up. These are:

MHOBA Strand 101

MHOBA American Oak Aged

MHOBA French Oak Cask

*There is another release, the Glass Cask which will be included here once I have completed my notes*

Let’s get right into them.

MHOBA Strand’s 101 – 58% abv – Pure Single Sugarcane Rum

Now called Strand 101 for its LMDW release, it remains however inspired by its namesake…the “Crazy Dane” Knud Strand. Knud has a history of working with large brands from Bacardi to Cachaça Novo Fogo and this bottling, like quite a lot of MHOBA ideas was a happy accident. Following an extensive sample tasting process Knud found himself with samples of the first run of the High Ester and the super woody 2 year Glass Cask Aged. He mixed the two together to hopefully balance the in your face funk of the High Ester and super woody profile of the glass cask. During a few tasting and presentation sessions Knud found that the blend proved to be popular. The desire was to have the product as an homage to some of Knud’s favourite products. The 101 to reflect his enjoyment of Wild a Turkey 101….Knud expected a direct proof to abv halving as per the US system but true to Roberts heritage, Imperial Proof was what we got. The Blue and Gold of the label reflects Knud’s love of Smith & Cross. But what is the liquid like.

Tasting Notes

Nose: Bright vibrant cane. Very pungent. Acetone. Varnish. Earthy root vegetables. Menthol. Herbal and perfumed. A hint of oak influence excerpts itself with a whiff of smoke. A lot of fermented fruit and wild strawberries carry through on the nose. It remains astringent and pungent with crisp green apples. It’s almost the best of both worlds. Vibrant youth and more balanced age.

Mouth: Beautifully sweet and oily entry accompanied by a lot of heat. The bite of a youthful spirit rules the early exchanges with fresh sugarcane, fermenting tropical fruit and cider. A lot of funk. On the mid palate the aged component begins to envelop your tongue and becomes quite tannic, drying out your palate. This leaves a medium length finish that develops from tinned fruit with fresh cream through coffee, an oaken influence and then into a warming peppery finale. Good balance of youth and maturity.

Very very enjoyable Rum……and if you’ve met Knud, you’ll see how it reflects his character…..approachable, warm and a little bit crazy.

4 / 5

I attempted to pair it up with Smith & Cross in a Mai Tai but it destroyed the Jamaican in standard recipe proportions so it needed re-balancing. Once I’d done that, it made an unbelievable drink.

MHOBA American Oak Aged – 43% abv – Pure Single Sugarcane Rum

Initially left to mature in large glass demijohns with wood fire charred and cut American oak staves, this Rum is then transferred to Ex South African Whisky casks for a second maturation period. It is then reduced and bottled.

Tasting Notes

Nose: Charred wood. Smoke. Caramel. Vanilla. Burnt wooden splints. Light sweet grain notes. Bonfire embers and powdered sugar. Warm fudge. Black pepper and pencil shavings.

Mouth: Heavy, drying oak. Damp cardboard. Grilled smoked meat. Warm charred timber…memories of woodwork classes at school. Butterscotch. The mid palate brings a slowly growing coffee influence. Dark chocolate. The charred embers of a fire on the beach. The dry and medium length finish is all dominant oak, light vanilla and powdered cocoa with lingering charred, smoked wood that grows increasingly bitter.

Not at the top of my list as far as the aged Rums go, but I do have a small cask sample of just the ex South African Whisky barrel matured and its a bit special.

3 / 5

MHOBA French Oak Cask Rum – 65% abv – Pure Single Sugarcane Rum

The French Oak Cask release sees a real step up in bottle presentation. It is housed within a hand constructed laser engraved bamboo box and the front and rear bottle labels are laser engraved bamboo. As you’ll note, this bottle was personalised and given to me at the UK Rumfest in October. Receiving it was a very humbling experience. The Select Reserve Rums are some of the Rums adjudged to be the most exceptional. In this instance the selected distillates have been matured for a minimum 12 month French Oak casks that previously held Cape Red Wine. These casks are brought in by MHOBA and are refurbished.

Barrel Charring with Hardwood Coals

The first eight French Oak casks obtained by Robert we’re stripped, ground and reassembled before toasting and sealing. Toasting would be via either the use of coals of an LPG torch. Each cask was filled over a two day period. First half filling with a single distillate Rum, Robert then sampled the cask blend the day after and make a decision on where to go next. Second distillate Rums are then added along with water for dilution reducing the abv to somewhere between 65 and 70%. Only when happy with the contents are the barrels sealed. The French Oak Cask reviewed here is taken from an equal blend of the best six casks from the initial eight. I do have an LMDW order bottle that has seen an additional six months in the barrel so I will update when that is opened.

Tasting Notes

Nose: The nose displays a lot of control for a 65% spirit. The oak is well integrated into the spirit but a perfumed and fragrant effect from the French oak is definitely present. A perfect balance of spiced notes from the barrel and classic, grassy sugarcane notes. Reminiscent of some truly wonderful aged agricoles. Bright acidic fruit, crisp apples. Growing tropical fruit….ripe mango. Guava jam. The oak is ever present but never overly dominant. Warming and spicy. Pencil shavings. Hints of red grapes and tart cranberries.

Mouth: Well balanced entry. Initially sweet, intensely so with a touch of powdered sugar and tropical fruit leathers. The freshness of the cane shines through. Intense moisture sapping dryness and huge amounts of grip on the mid palate from the French oak. There’s also a mineral quality. It remains soft though and never aggressive. Well balanced spice notes from the oak bounce off the vibrancy of the spirit to provide a fulfilling experience. The exceedingly long and intense finish sees sugarcane and tropical fruit mix with a huge oaken influence laden with spice, barrel charr and wet cardboard. Cranberry juice and succulent, crisp apples. A well balanced, fulfilling experience that will surprise a lot of people. Well crafted well executed rum.

Some producers have been working for years and have still not produced something as accomplished as this Rum.

4.5 / 5

I am fully aware that the Rums reviewed in this series will and may have moved on from these expressions. Different batches, harvests and more cask time are all components, welcome ones of being such a small producer and that fascinates me. It is also why I feel that MHOBA are so exciting as a producer, changing, developing and growing in both output and confidence all of the time. Robert has full autonomy over the distillates and therefore has the ability to experiment with fermentation methods, time, dunder, cane varieties and also with cask maturation enabling so many possibilities. Updates will be provided moving forwards.

© Steven James and Rum Diaries Blog 2019. Unauthorized use and/or duplication of this material, both written and photographic without the express and written permission from this blog/sites author and owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Steven James and Rum Diaries Blog with appropriate and specific direction to the original content.

MHOBA Rum – A South African Farm to Bottle Story

MHOBA translates as ‘Sugarcane’ from siSwati which is the language spoken by the local Swazi people.

Seemingly appearing from nowhere, MHOBA Rum have started to make themselves known in the Rum world. I first encountered them at the UK RumFest in London in October 2017 where they had three or four expressions of their Pure Single Sugarcane Rum that were creating a bit of a stir. I got chatting to owner, Robert Greaves about the brand and their expressions. I purchased two bottles in 2017 and stayed in touch with Robert. Fast forward to the UK RumFest in October 2018 and MHOBA are again present at both the Boutique Rumfest and the main weekend event. This time they have brought with them eight individual expressions and have taken the Boutique Rumfest by storm with a huge buzz surrounding them. This continued over the course of the whole weekend with MHOBA becoming a bit of a talking point among the attendees post RumFest. I knew that I needed to get some information written about them to hopefully get the limelight directed to a team that I thought were humble, engaging and willing to chat. The intention was to get a few questions out to Robert to build an interview……to find out his background, his motivation and his processes. It rather quickly became apparent that a simple question and answer interview would be underplaying the wealth of information that Robert has discussed with me during our conversations and I hope to recount the timeline from the beginning to that landmark 2017 Rumfest visit up to the recent delivery of a large order to LMDW in France which is a significant moment bringing the Rums of MHOBA to a global audience. So please stick with me if you will, as I attempt to tell you an in-depth and quite personal story of a proudly South African ‘Farm to Bottle’ Producer.

MHOBA Rum – A South African Farm to Bottle Story

Robert Redvers Greaves was born to an Artist Mother and a Mining Engineer Father in Johannesburg, South Africa in January 1978. The families of both his Mother and Father have been in South Africa for 3 or 4 generations. His Fathers lineage is entirely British as far back as the family have been able to trace, whereas his Mother is descended from Scottish and Dutch origins. Schooled and raised in Johannesburg, Robert then studied Mechanical Engineering at Stellenbosch and WITS Universities. Post studies, he began working as an Engineer in the Mining industry in underground construction contracting until his Father offered him the opportunity to take over his small Mining business. The business, built up since 1985 comprised two small-scale and marginal Mining operations in Mpumalanga, South Africa. Robert made the decision to relocate from Johannesburg to the larger of the two mines near Malalane to manage the mine himself and to save any costs associated with having to employ a Manager for the operation. As a result of the drastic deterioration of the Mining industry in the whole of South Africa over the course of the last 20 years, business income needed to be supplemented. To do this during the period of decline, they started growing sugarcane on their property to sell to the local Sugar Mill.

Robert and his family live on the Eastern side of South Africa near the border with Mozambique. Their property is just south of the Kruger National Park nature reserve in the Nkomazi area of Mpumalanga, not far from the small town of Malalane. By far the largest business in the surrounding area, and the raison d’être for the existence of town of Malalane is the recently renamed RCL Foods (previously TSB) Sugar Mill. The surrounding farms that provide the Sugar Mill with sugarcane alongside the supply of all other goods and services that the Mill requires provides a livelihood and to a certain extent, a way of life for the majority of the areas residents. Relocating from the ‘New York of Africa’……Johannesburg, to the rural farm life in Malalane had a profound and significant effect on Robert. Having an involvement with and being surrounded by the sugarcane farming culture influenced his lifestyle and his way of thinking. For most of its existence the mining business started by his Father had been marginal as far as profitability goes and with the steady and apparent decline of South Africa’s economy and the mining industry being plagued by problems, other opportunities needed to be identified to both supplement and possibly provide an alternative direction the keep the business running and the property maintained.

Growing sugarcane and being embedded in a cane growing region, sugarcane and sugarcane products provided a focal point for Robert to develop an opportunity involving their produce. Given the low value of unprocessed cane locally and his farm being relatively small in terms of yield when viewed alongside other larger properties in the area, producing sugar that could compete with the large expanse of the RCL Foods Sugar Mill was out of the question. Robert considered the production of alcohol from their cane. Without the knowledge that he now possesses, Robert initially thought that Rum was only made from molasses. Following a period of online research, he realised that Cachaca was a spirit made from fermented sugarcane juice. Socio-economic parallels are often drawn between South Africa and Brazil and the idea of making what he initially viewed as ‘South African Cachaca’ quickly gained traction as he had the sugarcane, and the similarities of their local cane growing cultures meant that locals could take to a sugarcane spirit as the Brazilian people had done. Robert had the vision of making a ‘Single Malt Whisky style spirit’ insofar as that he wanted it to be the product of batch / pot distillation and did not want to sully the distillate with colour or flavourings other than the oak. As he had not yet discovered Rhum Agricole, it would be a ‘Brazilian Style Rum’.

The eureka moment, the realisation of a future in Rum making came in 2013. Robert and his wife attended a wedding at the hotel Belle Mare Plage in Mauritius, and a man named Guillaume Graffeille was the person that helped him arrive at this pivotal decision.

Robert recalls sitting at the hotel bar and being mesmerized by the quantity and variety of available Rums on the back-bar and it far exceeded anything that he had previously laid eyes on. Fortunately it seems, the barman had disappeared for a short while and as he perused the weird and wonderful bottles on display, Robert was assisted by a bald chap who was buried in paperwork and appeared to be a Senior hotel staff member. His name was Guillaume. Rather reluctantly, but whilst retaining every ounce of his professionalism, he broke away from his administrative tasks to assist Robert in his requests to view some of the numerous bottles on the shelves and also provided answers to the numerous elementary questions being asked. Robert specifically recalls that at one distinct point the man asked, “Where do you come from?” and when the question was answered with “South Africa”, his retort was, “Yes, you guys know nothing about rum. You only know grapes, wines and brandy”. As discussions progressed, it was reveled that the hotel had a selection of 120 Rums and that they enjoyed being able to take guests on a “Rum taste tour” with Rums sourced from across the globe. “Wherever there is sugarcane, there is Rum” advised Guillaume. It was at this moment that the penny dropped for Robert. Just about everywhere that sugarcane is grown, some form of Rum is produced, and in the area that he lived it was actually one of the exceptions to the rule. If Rum worked in so many other diverse cane growing locations, why not where he lived? Surely all that he needed to do was make good quality Rum? Its at that point that Robert seemingly went headlong down the path to becoming a bit of a Rum maniac.

Early Efforts

Upon returning from Mauritius, Robert immediately started juicing his sugarcane by hand in a vice on a workbench making small 10 litre fermentation batches that could take several hours. These were left to ferment in buckets. He also hand built his first rudimentary stainless steel gas fired still during that first fermentation from what was once a milk urn. Numerous batches of ungodly and revolting distillates were produced, all enthusiastically tested by him and anyone else that was unfortunate enough to be near and willing enough to try……there were not many repeat volunteers. With a lot of persistence, a willingness to try many variations on his fermentation’s and several revisions of small handmade stills, Robert managed to produce what he (at that stage) and the majority of willing volunteers believed was a really good, “smooth” spirit by triple distilling to 95% abv. He continued to experiment and perfect the pure spirit that he wanted to produce at that stage and as feedback became more and more positive he decided to apply to obtain a license to allow the production and sale of his own Rum commercially.

Following months of objections from neighbours, several consultants and countless lawyers bills, Robert eventually received his “Micro Manufacturers Liquor License” and excise account from the relevant South African tax authorities in June 2015, opening the gate and allowing him to produce and sell MHOBA Rum. Very much a ‘hands on’ and practical chap, he built their first roller cane press and a 200 litre stripping still which allowed them to do quite well in terms of selling their “White” and “Glass Cask” aged Rum in the local market. This is even more impressive given that this relative success of their first two Rums occurred in a country that has considerably lower levels of Rum knowledge and appreciation. Positive feedback was raining in from “those in the know” within the industry and that is the point when Robert met Andy Kiloh, also known as the RumBro. Andy was able to carry samples of the MHOBA output to The Miami Rum Festival in 2016 and he returned with encouraging feedback and opinions from those introduced to the Rum. A key driver to the 2017 Rumfest appearance was a visit by Robert to the Mauritius Rum Festival in 2017 as this is where he met Ian Burrell. Appearing to be quite taken with MHOBA Rum, Ian invited Robert to the UK Rumfest a little later that year. Ian’s enthusiasm for MHOBA was a huge confidence boost for Robert as it was the first time that he understood that there would be a potential market far beyond local sales. UK Rumfest 2017 proved to be a steep learning curve as it presented the ability to taste Rums that were previously unheard of to him and more importantly he had the opportunity to meet the producers whilst simultaneously receiving very positive feedback from some well respected names. He specifically received some constructive advice and feedback from Richard Seale at the 2017 UK Rumfest and that advice has been key to allowing Robert to raise his game quite substantially. Having some of the most knowledgeable people in the Rum world compliment his Rum was a big deal to Robert and this alongside the constructive feedback provided the energy required to elevate MHOBA to bigger and better things.

Amazing how economic situations can give rise to new opportunities to motivated and hard working individuals and the story is testament to the fact that chance meetings and words of encouragement can change the trajectory of a persons path by allowing them to focus on new goals that may have been in front of their eyes the whole time.

Processes

The “Farm to Bottle” aspect of MHOBA is no empty moniker. As a team and a producer, they do things themselves. From owning the land where their cane is farmed, manufacturing their sugarcane press, their fermentation vats, their stills, their labels etc, Robert has created an environment whereby they may be reliant upon materials, but they know how to repair equipment and he knows the distillation equipment intimately….after all, he built it. The following information will cover the sugarcane from fields to harvest, sugarcane pressing, fermentation, distillation, maturation and bottling and thanks to Robert, it will be littered with some pretty unique images.

Cane Fields and Harvest

This is a crucial stage in MHOBA‘s rum making and a major part of what differentiates them from a molasses producer or even a cane juice producer buying juice from someone else. The varietals that do well in their area were developed by the South African Sugarcane Research Institute (SASRI) which makes them unique internationally, and when combined with the local climate, soil type, magnesium rich water and local microbials gives MHOBA rums a most definite, distinctive and unique terroir.

Very few people (even in the international rum geek fraternity) really understand how much work goes in to being a true “Farm to Bottle” producer. They plant their own cane, grow their own cane, cut and de-trash their own cane by hand and then shred and juice the cane using manually operated, hand fed machinery. There is a massive amount of work, all done by the MHOBA team, that goes in to producing each and every litre of their pure sugarcane juice wash. Once a tank of freshly squeezed juice is fermenting, the rest of the rum making process is then relatively easy in comparison to getting that juice ready for the yeast.

Another thing worthy of note is that MHOBA have begun the process of becoming accredited as the first fully organic sugarcane producer in South Africa.

Sugarcane Pressing

Robert has built two types of cane presses in the last 6 years. The first was a more conventional roll type press which had two counter rotating large steel wheels which squeeze the cane sticks between them. This old press is no longer in use, though is pictured below:

Original Redundant Cane Press

Press Feed Conveyor

Cane Press Location

They utilised the rotating roller press for about two years before Robert designed and then built the current press, which is totally unique. He have never heard of anyone else using a press of this type. The press works on a batch principle which makes it slower in terms of cane throughput, but it is significantly more effective in extracting the juice from the cane. It is basically a large, thick walled steel pipe which is filled with pre-shredded sugarcane. This shredded cane is then pressed with a hydraulic plunger which presses the shredded cane with a force equivalent to a weight of about 60 tonnes.

Removing Spent Bagasse

The process of juicing sugarcane at MHOBA is as follows:

  • After cutting and de-trashing (removal of the cane stick tops and leaves which contain no juice) cane by hand it is placed in heaps in the fields which are again loaded by hand on to a small tractor-trailer which delivers the freshly cut cane to the cane press
  • The cane sticks are hand fed into a hammer mill which shreds the cane into a more compressible coarse pulp. This pulp fills a stainless steel hopper or bin which is the correct volume to fill the press
  • Once the feed bin is full the hammer mill is stopped and the hopper contents are fed by conveyor belt in to the barrel of the press
  • The full press barrel is then moved sideways into the press position underneath the hydraulic ram and the ram moves downwards by means of a hydraulic cylinder and compresses the shredded cane at the bottom of the barrel
  • The pressure on the cane is maintained for several minutes until no further juice is seen exiting the bottom of the barrel
  • Once the press is completed, the ram is retracted and the cylinder is then moved sideways to the bagasse ejecting position and a smaller hydraulic cylinder and ram are used to push the plug of compressed bagasse out of the bottom of the cylinder on to a conveyor belt which places the spent bagasse on a stockpile
  • A portion of the spent bagasse is mixed with cattle and chicken manure to form an organic fertiliser which is returned to the cane fields and the remainder of the bagasse is burnt to generate heat for the stills
  • The cane press produces between 1 and 4 000 litres of pure cane juice per day

Pure Nkomazi Sugarcane Juice

Cane Juice Collection Tank

Fermentation

MHOBA grow 6 or 7 Sugarcane Varietals on their farm which are supplied to the local sugar mill. There are two dedicated varieties grown in their fields which are dedicated to the production of MHOBA Rum. These are N57 and N36. Both are South African developed varieties, developed by SASRI (South African Sugarcane Research Institute). It is these two varieties that as mentioned above, MHOBA are in the process of acquiring organic certification for.

2000 litre Fermentation Batch (7-10 Day)

Because MHOBA shred their cane prior to pressing as mentioned above, quite a bit of the naturally occurring yeast is washed off the outer portions of the cane when it gets squeezed and ends up in the juice. Their press is also quite slow to operate so it takes several hours to press a full batch of juice and during its time in the tank the juice begins to ferment naturally. Once a full 1000 litre batch has been pressed it is usually fermenting moderately using only the natural yeasts. They then transfer the 1000 litre fermentation batch to the fermentation tanks and add a commercial yeast which is standard baking yeast, Saccharomyces cerevisiae. Yeast pitching and variety are uniform for all of the currently released Rums thus far, including the High Ester long ferments. Robert has experimented with some 100% wild ferments but they have not yet made it to sale.

Dunder / Long Fermentation Batch (21 Day)

MHOBA do not use temperature control during fermentation as due to the small size of their batches, the critical mass has not yet been achieved in terms of the yeast activity raising the temperature of the ferments to a detrimental level. They have recently begun using 2000 litre fermentation’s in anticipation of their new 1000 litre pot stills which will be fired up over the next few weeks. These larger batches are getting significantly warmer than the 1000 litre batches. If the decision is made to step up from 2000 litre batches, cooling may well be required. All normal ferments last for between 7 to 10 days.

Dunder / Long Fermentation Batch

High Ester ferments are for a period of 21 days. The dunder in these High Ester batches is added when the cane juice is transferred to the fermentation tanks so the initial few hours of natural / wild fermentation is the same for all batches but once in the tanks, dunder is added before the commercial yeast.

Dunder / Long Fermentation Batch at the Halfway Point

Distillation

Robert has built several pot stills since starting to make rum, and he has never actually distilled anything in a still that he didn’t make himself. The lighter distillates created by Robert didn’t hold up too well to cask maturation initially and following his discovery of ‘Single Blended Rum’, but not having the required still types, Robert decided to blend heavy single pot distillates with lighter twin distilled high ABV Rums to mimic a single blended distillery output.

The Three Pot Stills

The pot stills in use at MHOBA have all been made from copper and stainless steel. Copper contact with the vapours and distillate during distillation is very important as it helps with removing sulphur containing compounds from the new make spirit. The pots, which hold and heat the fermented sugarcane batches are made from 316 stainless steel as this section of the still needs to be structurally strong to support the weight of the still and the batch of fermented sugarcane juice.

The Three Pot Stills

The pot portion of the still contains no copper as its influence submerged in the wash has almost non existent effect on the taste of the distillates that the still produces. The structural parts of the tall narrow upright necks of the stills are again fabricated from 316 stainless steel for it’s strength, ease of fabrication and resistance to corrosion.

Pot Still Temperature Display

Condenser Piping Arrangement

Within the outer stainless steel shell of the still necks is a lot of copper. The entire vapour path inside the still necks is packed with copper wool plates and pipes which they make themselves. There is significantly more copper contact in the vapour path in their stills than in a traditional copper alembic type still or even in a more modern copper bubble cap type pot still.

Condenser Assembly

Condenser Return Manifolds

Robert is a firm believer in “form follows function” and stainless steel is the natural choice for the structural components of a still as it is strong, chemically neutral in the process and is easy to cut, shape and join using conventional fabrication techniques. Copper required for its chemical influence on the distillate and it’s excellent heat transfer properties is machined to maximise its surface area and placed in the vapour path of the still where it is exposed to the rum distillate in vapour and liquid states.

Drilling Copper Spacer Plates

Drilled Copper Spacer Plates

As mentioned above and clarified with the images of the components being fabricated and assembled, there is more copper in contact with the MHOBA rum during distillation than most conventional copper stills but the copper in their stills is not visible once they are assembled.

Maturation

The Team

The maturation of MHOBA Rum occurs in a steel and galvanised sheet metal warehouse which allows the benefits of the hot humid South African climate to act upon the casks and the rum they contain. There is much talk internationally of tropical vs continental ageing in rum, MHOBA have something similar to Caribbean tropical ageing with heat and humidity except that their temperature variations are more extreme both daily and seasonally as they are not on a small island where temperatures are moderated by the surrounding ocean.

Barrel Warehouse

Robert expects to be able to accommodate around 1000 casks in their current warehouse and they will hopefully need to start building a second warehouse in the not too distant future. 

Barrel Racks

Although MHOBA are still extremely small and have only accumulated around 100 casks of which 20 are ex-American whisky casks with the remainder being European oak casks which are all ex-Cape red wine casks. Their casks are of various sizes between 200 litre Barrels and 500 litre Puncheons all of which are previously used casks and many of those are completely dismantled and refurbished by the team before being filled the rum. Their oldest cask aged rums are currently almost 2 years old. 

American Oak Ex South Africa Whisky Casks

As mentioned above, they have mostly French and American oak casks……and now one Hungarian oak barrel.

Refurbished Hungarian Oak Cask Containing MHOBA Rum

Some of the casks are left in the state they were from their previous use as they are used for secondary maturation (finishing) and other are completely dismantled and refurbished and re-toasted to get much more oak influence into the rum. When charring with hardwood coals, the cask is rotated about a foot at a time and then left for around 5 minutes before rolling another foot or so. Each cask is usually subject to 3 or 4 full rotations until desired char levels are achieved on the staves. The cask is then stood upright so that the coals char the inside of the cask head. The head that has been removed is toasted separately by using hot coals.

Barrel Charring with Hardwood Coals

Barrel Medium Toast with LPG Torch

Bottling

The bottling of MHOBA rum is very basic and entirely manual as is the rest of their rum-making process.

Hand Filled Bottling

Rums which are blended and or diluted to a specific ABV are blended in stainless steel vessels and the blend and ABV are adjusted to suit. The ABV is roughly checked using density based measurements via a Hydrometer or Digital Portable Density Meter until the blend is correct and the rum is then left to rest to allow as much sediment to precipitate and settle as possible.

Rums which are blended and / or bottled at a specific ABV are first blended in stainless steel and roughly proofed using a hydrometer

ABV Estimation Using a Density Measuring Device

The batch of rum is then filtered at ambient temperature using a stainless steel plate filter which removes the majority of solids in the batch from ageing and / or dilution and blending. The rum batch ABV is then finally adjusted and checked to be within the allowable tolerance of the stated ABV using a highly accurate alcolyzer system. The batch is then re-filtered using cotton wool plugs or filter paper and then stored in sealed glass demijohns before being poured in to the final bottles which have already been labelled.

Rum Filtering

The MHOBA cask strength rums and single batch white rums are not diluted or adjusted in any way and are bottled at the ABV at which they were maturing in cask or at the ABV at which they were distilled in the case of the Pot Stilled High Ester Rum. These rums are only filtered through a cotton wool plug before being bottled.

ABV is Finally Measured Using an Alcolyzer

Robert is unbelievably proud of the fact that so much of the final product that is produced is made by the team at the distillery. He personally designed nearly all of the labels and they print and engrave all of the labels at the distillery before applying them to the bottles.

Printing of Foil Labels is Done at the Distillery

The Premium aged rums are labelled with thin laminated bamboo which is laser engraved and cut by two laser engraving machines which run at the distillery.

Laser Engraving and Cutting of Bamboo Labels is done at the Distillery

These same rums are then packaged in individual boxes which are also cut and engraved by hand before assembling the pieces to form the final boxes.

Pure Sugarcane Happiness

MHOBA are currently producing 10 expressions. The original two of these rums are only for sale in South Africa and the remaining 8 are predominantly aimed at the export market but are also bottled in 750 ml and are available in South Africa.

Robert with the 8 expressions for export

Their rums vary greatly from light easy drinking, versatile multiple distillate, lower ABV rum right through to heavy, robust High Ester, dunder fermented rum which is bottled at distillation strengths of 60 to 70% ABV.

Export order for LMDW

Their aged rums vary considerably too with some aged only using American oak and another only in French oak casks.

Select Reserve Rums Before Being Sealed and Placed in Individual Bamboo Boxes

They are also now maturing rums which are not yet available in various other casks including Hungarian oak, once used “fresh” Bourbon casks and ex South African whisky and wine casks. The Whisky casks have been a mixture of ex-South African Grain Whisky and Malt Whisky casks, with the Malt Whisky casks having a peaty aroma. Something that I think will work very well with their distillates.

Hopefully this has been an informative read for you and my thanks goes to Robert for the time that he has spent recounting the details to me and the level of information which he has shared. There is a companion piece that will follow this article and within that I will cover each of the available MHOBA Rums that are available from LMDW.

*All images provided by Robert for use within this article have either been taken by Robert or by Sven at Phonix Capture

© Steven James and Rum Diaries Blog 2019. Unauthorized use and/or duplication of this material, both written and photographic without the express and written permission from this blog/sites author and owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to Steven James and Rum Diaries Blog with appropriate and specific direction to the original content.