The aging process is considered to be the most significant aspect of the rum manufacturing process because rum improves with age. During aging many changes occur as a result of the oxidation and selective diffusion though the pores of the oak barrel and various chemical interactions. In general, oak wood barrels are used because they do not contribute offensive odors or tastes to the rum during the ageing process.
Alcohol concentration
Alcohol concentration is usually rated using by the percentage in volume of alcohol (% abv). 1 litre of a 30% abv spirit contains 30 cl of pure alcohol. Another measure is the US proof wich is twice the value of % abv. 1 litre of a 30 US proof spirit contains 15 cl of pure alcohol.
A.O.C. stands for Appellation d'Origine Contrôlée. It's the french translation to EU Protected designation of origin. You can find on this site the "Rhum Agricole Martinique" AOC decree and its description.
Añejo rums are aged for a couple of years, there is not a time standard, and they usually have brown or caramel color.
the dry dusty pulp that remains after juice is extracted from sugar cane or similar plants. Bagasse is often used as a fuel to provide energy to the facility.
Is the secret to fine rum. It allows the master blender to use many different types and styles of rums to create a particular blend or brand. The skill of blending involves the mixing together of light and heavy type rums of different ages that have been carefully analyzed and selected by the blender for the characteristics specified. The different rums are allowed to fuse together to give the blend a smoothing effect.
A tall, heavy conical glass with a thick rim, designed to be combined with a Boston tin to form a shaker. It can also be used as a mixing glass for stirred drinks.
Sugar concentration measuring unit. A 25°Bx (brix) liquid contains 25g of sugar and 75 g of water, in other words, 25g of sugar in a 100 g juice.
C4 plants
C4 plants are plants which use more carbon to grow than average plants. They are hence far more efficient in carbon trapping and require usually more water and heat than C3 plants. Sugarcane is a typical C4 plant.
Centrifuged Yeasts (Fermentation)
Yeasts can be put to "sleep" by dehydration through centrifugation. This technique is seldom used apart from industrial processes as the time lag between fermtation beginning is quite high. Contamination risks by other strains are hence higher in non fully controlled environments.
Coupage (Fermentation)
Seeding method consisting in transferring part of a tank in full fermentation to another tank and completing the two tanks of sweet juice. This method makes it impossible to reseed with new yeasts. However, the yeasts eventually degenerate, it is necessary from time to time to renew them.
Coupette (Glassware)
Commonly referred to as a “Margarita Glass”, it can give your Piña Colada a rather interesting look.
Ideal for rum drinks which are served tall, but not very long.
Discontinuous Fermentation
Discontinuous fermentation is opposed to continuous fermentation where liquids from drained the fermentation tank are replaced by fresh juice, allowing a continuous fermentation.
After fermentation, the fermented wash is fed to the still. Distillation is the process of boiling the “dead wash” and condensing its vapor to produce the alcohol that is collected. The distillation process is done to separate and concentrate the alcohol component of the liquid mixture. Puerto Rican rums stand out because of the manner in which the raw material is distilled. Contrary to other European methods, which use the pot still, in Puerto Rico they use column stills, which guarantee consistency and a better final product.

Is a vital process. The molasses is diluted with water to reduce the sugar content to approximately 15% and a pure yeast culture is added to the mixture. The yeast cells convert the available sucrose to ethyl alcohol and carbon dioxide with the release of heat energy. This mixture is called the “live wash”. The liquid left at the end of the fermentation process (which lasts approximately 30 hours) is called “dead wash” and is used for distillation.
Enrichment Section
The section of a column situated above the feed point. The trays of this section do not handle the liquid fed into the column but rather make the vapour coming from below richer in alcohol.
Technical name for alcohol.
Which releases heat, mainly said of chemical reactions.
In the French West Indies, distilleries still in operation are said to be fumantes (French for smoking).
Hectolitres of pure alcohol. Measurement unit used for distillery production or capacity. It measures the alcohol produced and not the volume of spirit produced. It is therefore independent from the dilution of alcohol in the spirit.
Heads are the first parts coming out of a distillation process. Heads are made of the most volatile parts of the liquid to be distilled. In alcoholic distillation, heads are usually made of methanol and acetone, unpleasant or event toxic products. That's why heads should be discarded to maintain the quality of the produced spirit.
Heart is the part coming out of a distillation process between heads and tails. Heart is the part retained to make the spirit.
Master Batch (Fermentation)
Master batch is pitching technique where a first batch is pitched and heated to foster fermentation. As soon as fermentation is well established, the batch is mixed with other batches as a starter.
A thick syrup left after all the raw sugar has been extracted during the refining process. Its colour usually ranges from light to dark brown. Molasses are the main ingredient to non agricole rum production.
Acidity measurement unit of a liquid, usually an aqueous one. The higher the pH is, the less acid the solution is. A pH of 7 means a neutral liquid. Vinegar pH usually ranges from 2 to 3 and Sodium hypochlorite has a pH higher than 11.
"Pitching" is term use in brewery and means adding yeast to the liquid to be fermented.
A shoot sprouting from a plant base, as in the banana, pineapple, or sugar cane.
Harvesting techniques which leaves the root system along with part of the stem. This techniques simplifies field management (nor plantation required for fresh plants) and allows a stronger and earlier start of the next season.
Rectification is the process of repeated distillation of a liquid to produce a spirit with a high concentration of ethanol. Rectified spirits are stronger in alcohol but usually with weaker aromas. This technique is strictly forbidden by the agricole rhum specifications.
In the distillation context, reflux is the part of the condensed vapours that are reinjected into the distillation column on the upper part of the column (in the enrichment section). Reflux reinjection provides better extraction rates for the column, producing spirits with higher concentration in alcohol and aromas.
Saccharomyces are yeast (fungi genus). Yeasts are used to porduce alcohol or to make the bread rise. Most common yeasts are Cervisae (from latin cervisae: cervoise, a kind of beer).
A starter is a brewery term designing a solution of highly active yeasts which is pitched into the solution to be fermented. A starter reduces the lag time before the beginning of fermentation, hence reducing contamination risks from other strains of yeasts or bacterium.
Stripping Section
The section of a column situated below the feed point. The trays of this section make ascending vapour bath in pools of descending liquid. Vapours get richer in alcohol and aromatic compounds as liquids get poorer.
Tails are the last parts coming out of a distillation process. Tails are made of the least volatile parts of the liquid to be distilled. In alcoholic distillation, tails are usually made of propanol and organic compounds. Tails are highly aromatic though sometimes in an unpleasant way. Finding the separation between heart and tails is a difficult quest between pleasant and unpleasant aromas. Spirits without any or few tails tend to be without any aroma, spirits with more tails have more aromas, the difficult point being to find the right time to stop before unpleasant aromas.
Terroir ([tɛʁwaʁ]) is a word coming from the French word terre(land). At first used in the wine context, it denotes the specificities of a geographic origin, its soil, climate, growing techniques,... All those specificities contribute to the product uniqueness.
Tray (Plates)
Trays or plates are horizontal devices inside a distillation column. Each tray represents at a different set of temperature and pressure an equilibrium between vapour and liquid. Trays look much like plates with various devices designed to force contact between liquid and vapours.
Vésou is the way fresh sugarcane juice is commonly named in the French West Indies.
vin is a generic term used in distillery process to name the the alcoholic liquid which will be distilled. In the rhum context the vin is made of fermented vésou.
Vinasse is the liquid left after the distillation and the removal of alcohol from the vin. Vinasse can be used as a fertilizer or to produce biogas in an apparatus called thermophilic digester.