Rum Production Cycle
The distillery is a specialised work environment. The presence of alcohol vapours means that particular care is needed because of the risks of fire. Precautions are essential! For example, no smoking and extreme vigilance is required if undertaking welding works.
3 indispensable controls for weighing:
- Weight and Brix Value is used to help determine planters’ pay. (The Brix value, measured with a refractometer, is the amount of soluble solid matter present in the juice, i.e. sugar and impurities).
- Weighing also helps to assess the quality of canes - condition (cleanliness and freshness) and acidity (pH) level.
- Weighing is carried out on samples taken from each delivery. The information collected is computerised. There is no place for chance - every step is taken to ensure fair and objective payment of planters.
The negative effects of dirty cane:
- The sugar cane should be clean (the presence of debris = blockage of or damage to the roll mills)
- The cane must be pressed on the same day that it is cut (loss of freshness = loss of sugar, alcohol and flavour)
- Equipment must be kept meticulously clean (poor hygiene= the risk of bacteria developing)
- Poor quality juice
- Disruptions to fermentation process
- Increases in energy consumption
- Premature wear and tear of cutters
After being weighed, the sugar cane is taken to the conveyor.
It is imperative to provide an even and regular supply of cane so as to prevent blockages and ensure optimum preparation.
The cane loader has the following responsibilities:
- To ensure that there are no stones or other debris in the load as this could damage the conveyor and cane cutters.
- To load the conveyor with an even quantity in order to prevent blockages.
- To adhere to safe operating regulations.
This stage involves breaking the fibres of the cane in order to facilitate juice extraction. The cane cutter chops the cane into pieces. At Damoiseau, there is also a shredder which tears the pieces of cane into even finer strands.
Pressing and extraction
The marvels of bagasse: some is used to supply energy to the distillery, some to fertilise the plantations and some for animal feed.
- The shredded cane passes through a series of roll mills which extract the juice, known as vesou, and expel the bagasse (fibrous residue).
- To facilitate juice extraction, water is added to the bagasse (quantities vary in accordance with the density of the juice); this process is known as imbibition. If necessary, sulphuric acid is added to maintain a pH level of 4-5
- A filtration system gradually eliminates bagasse residue suspended in the air in order to leave a residue-free juice.
The pressing uni t: conduct and maintenance.
The flow of cane to the mills needs to be managed to ensure a regular supply and a smooth pressing process, and to prevent blockages.
Without cleanliness there can be no quality (100% vigilance = 0% incidents)
Daily cleaning of all equipment (roll mills, conveyor, sampling basin, etc):
- Eliminates the risk of bacteria developing
- Creates the most advantageous conditions for successful fermentation.
- The cane juice is transferred to stainless steel vats where it ferments, upon contact with yeast, for approximately thirty hours.
- Sugar cane naturally contains ingredients to facilitate fermentation. Yeast simply accelerates the process.
- The liquid produced by fermentation is known as grappe which has an alcohol strength of 4 to 6°.
Three procedures for stimulating fermentation:
- Direct pitching: a yeast preparation is added to the vats (0.2g per litre) before they are filled;
- Blending: part of a vat’s content is distilled and the rest is used to pitch another vat;
- Drawings: the drawings are used to pitch a new vat.
In accordance with the directions of his or her manager, the chemist:
- Analyses the raw material on its arrival (pH, Brix value, condition)
- Prepares and monitors the yeast. (The yeast is made of good bacteria which need to be taken care of. Excess heat and the development of undesirable bacteria should be avoided)
- Monitors fermentation indicators (temperature, action of the yeast, density of juice, etc)
- Decides when to end fermentation, depending on the density of the juice.
Hygiene at all times: Vats must be cleaned before they are refilled
Three points to watch for :
- Overflows of foam, which are still possible in spite of the use of sensors.
- The temperature of the vats, which are maintained at around 35°C either by an internal cooling system or by spraying the outer walls of the vat with water.
- The action of the yeast, which can be checked by taking occasional samples.
This process separates the alcohol from the cane juice by taking advantage of the volatility of different compounds. Only the most volatile substances will be found in the end product.
The colourless rum obtained after distillation is known as Grappe Blanche and has an alcohol strength of approximately 89°.
The column or continuous still is a key instrument in the distillation process. It comprises a column of perforated trays with a “wine heater” (chauffe-vin). The fermented cane juice arrives at the top of the still and cascades down from tray to tray gradually releasing vaporised alcohol. Steam enters the still at the bottom and takes up vaporised alcohol as it rises. The alcohol, in vaporised form, concentrates at the top of the still and then passes to the condenser where it returns to a liquid form.
Marrying economics with ecology.
- 1. The distillation process produces a liquid residue rich in organic matter known as vinasse. Research and development into the processing and uses of vinasse, initiated five years ago by Damoiseau Rums, has led to the implementation of a system of evaporation/concentration.
This system involves concentrating the vinasse using steam produced at the distillery (this steam is generated through combustion of a proportion of the bagasse) and then mixing this concentrated vinasse with the "excess bagasse" not used in the steam production process. The result is a 100% natural fertiliser which can be used on the sugar cane fields.
- 2. Other systems for making productive use of vinasse include:
- - 2.1 Settling tanks and spreading vinasse on sugar cane fields
- - 2.2 Methanation in order to generate energy; a method reserved for the largest distilleries.
Before it is ready to drink, rhum agricole blanc is stored in oak barrels for approximately 6 months. During this period aeration and homogenisation take place.
- On leaving the column still, the rum is poured into a vat and then stored in wooden barrels. Before bottling, it is blended with demineralised water to achieve the required strength of alcohol.
- In this way, white rhum agricole with a proof of 40, 50 or 55° (according to demand) is produced.
- The barrels and alcohol content are checked regularly.
This involves storing the rum in oak barrels for at least three years. During this time, certain aromatic compounds evaporate (the evaporated volume is known as the "Angels’ Share") and the rhum agricole takes on tannins and woody notes. The golden brown colour acquired is a product of the rum’s long storage in a wooden container.
To produce one litre of ten year old rhum vieux
, 2 litres of white rum need to be stored and aged.
Different Rhum Agricole products:
- RHUM BLANC : Stored for approximately 6 months before bottling.
- RHUM AMBRE : Stored for between 12 and 18 months in oak barrels
- RHUM VIEUX : Aged for a minimum of 3 years in oak barrels with a capacity of less than 650 litres.
Distillation is a seasonal activity but bottling is carried out throughout the year in accordance with demand from our clients.
Our rum is sold in various packages: bottles, boxes, flasks, and miniatures. It is not possible to use machinery for this last type of packaging - it has to be done by hand.
The Distiller’s brand image and packaging is also a focus of great care and attention.
The sugar cane season begins in February and ends in July at the latest.
Canes are at their most abundant in March and April and during this period the Damoiseau distillery works from 3 o'clock in the morning until 4 o'clock in the afternoon in two shifts.
It is essential to take advantage of the time when canes are at their most abundant to produce as much rum as possible. In May, heavy rain can reduce the richness of the crop and even hinder harvesting because the cane fields become impassable.
The hurricane season, which begins at the end of June every year, can also disrupt harvesting if a particularly early tropical storm or hurricane arrives over Guadeloupe.
From August until the end of January the following year, the abundance of the sugarcane deteriorates so much that it becomes almost impossible to extract enough juice to distil rhum agricole.
Between August and January, activity slows down but it does not stop altogether. The quiet season is a key time for preventative maintenance works, to ensure that the production tool remains operational, and for modernising the distillery to improve safety, quality, and energy efficiency.
The next season therefore benefits from the quiet season. With updated and finely tuned equipment and the latest technological innovations installed, Damoiseau Rhum Agricole improves in quality year-on-year.
Three Golden Rules
- The cane cutters, rolls, etc are fully dismantled, cleaned and reassembled.
- Tools are precision tuned (speed of mills, spacing of rolls, etc) as errors in adjustment will make them inoperative.
- The column still is dismantled, scrupulously cleaned and leak-proofed.