Rum

Rum, with its rich history and diverse flavours, originating in the Caribbean centuries ago, has found its way into glasses around the world.

At the core of rum production lies sugarcane. The sugarcane is crushed to extract its juice, which serves as the raw material for rum production. Like all agricultural ingredients, the location and conditions where it is grown affects the flavour profile of the sugarcane.

The sugarcane is milled to extract the water and sugar juice. Production using this fresh sugar cane juice is called ‘rhum agricole’ and popular method in the French Islands. A much more common method is ‘rhum traditional’, that uses molasses.

Whatever the sugar cane base ingredient, it is fermented with water and yeast to produce a ‘wash’ of 5-10% alcohol/volume. The yeast initiates the transformation of sugars into alcohol. This process can take anywhere from a few days to a couple of weeks, depending on factors like temperature and yeast strain. In addition, yeast also initiates chemical reactions in the wash to create compounds such as aldehyde, esters and acids, which are collectively known as congeners. These compounds contribute to the flavour and are either encouraged or discouraged depending on the type of yeast used and the temperature of fermentation.

It is worth remembering that distillation can only separate and remove flavours – while fermentation generates the flavour in the first place.

When considering molasses, which is rich in all the nutrients yeast needs, it needs to be slowly introduced to progressively higher concentrations of molasses. This fermentation can sometimes be a three or four step process. And the range of time for fermentation can be from 24 hours to as long as a fortnight. A longer, slower fermentation will result in a heavier, more acidic wash due to other contaminating bacteria also given time to reproduce.

Next in the process is distillation which separates the alcohol from the fermented liquid. When alcohol is concentrated during distillation, the levels of congeners are reduced, leading to lighter the rum.

Rum distillation is typically carried out using copper pot stills or column stills, each method imparting its own character to the final product. The distillate undergoes multiple rounds of heating and cooling, gradually concentrating the alcohol and refining its flavours. Rum produced from a pot still or single column distillation is usually described as heavy, which rich, syrupy flavour to match their dark colour.

Light rum, from multiple-column stills, have a short fermentation and with a more subtle, refined odour and texture.

In Australia, rum production has seen a resurgence in recent years, with distilleries embracing traditional techniques alongside innovative approaches. While Australia may not have the historical association with rum like the Caribbean, its distillers are making their mark with unique expressions that reflect the country's terroir and craftmanship. Aging in oak barrels adds depth and complexity to Australian rums, with distillers experimenting with different woods and aging techniques to create distinctive spirits.

Rum production can be considered a delicate blend of science, art, and tradition, with each step contributing to the final product's character. And in Australia, with our expansive sugar cane cultivation, rum production continues to thrive.