Fermenting Tobacco: Overview and Success Factors

After harvesting, the tobacco leaves are placed in so-called tobacco houses. Here, the tobacco leaves are dried. This process enables the tobacco to undergo fermentation. The drying methods are mainly classified into natural and artificial processes. Natural methods can take between 30 and 90 days, while artificial methods only take 3 to 5 days. The most common method is air curing (Air-Cured). Drying the leaves is one of the trickiest parts of cigar production. Tobacco leaves that are of excellent quality at harvest can be ruined through poor handling during drying.

Why is Cigar Tobacco Fermented?

The fermentation of tobacco is a controlled biochemical process used to prepare tobacco for cigars. Through natural enzymatic reactions, tobacco leaves break down compounds, leading to the formation of new flavor compounds and the characteristic taste of cigars.

Fermenting tobacco is therefore a crucial step in cigar production. The previous drying ensures the correct moisture level. Drying and fermenting tobacco are closely linked, as both affect the moisture levels and chemical properties of the tobacco.

Natural Drying Methods

Natural drying methods include air drying (Air-Cured) and sun drying (Sun-Cured). During this process, the tobacco loses moisture and develops initial flavors. Even fermentation is crucial for flavor formation, and the tobacco should not crack due to overly rapid drying.

Typically, tobacco leaves are threaded and attached to poles for drying. In Cuba, the leaves are threaded in pairs and then hung side by side on a pole. In other methods, the leaves are pierced at the end of the stem with a needle, strung onto ropes, and hung to dry. Additionally, three to four leaves can be pressed together, tied with a thin thread to sticks, and then hung horizontally in drying barns.

Air-Cured Tobacco

This method is used by most manufacturers today. In traditional drying barns or tobacco houses (called "casa de tabaco"), the leaves are hung as described above. These drying barns, usually made of wood, also have windows and doors. These are necessary to regulate temperature and humidity through regular opening and closing.

What happens during air drying?

The drying of the leaves must ensure that they maintain their cellular life, even though they are no longer on the stem in the field. The leaves continue to "live" after harvesting, but their condition is comparable to a field suffering from severe water shortage, without supply or nourishment. The leaves begin to live off their reserves in this state.

In the first phase of leaf drying, deep chemical transformations occur. These result in significant loss of solids and moderate water loss. The slow loss of water over time leads to beneficial biological and chemical changes. The tobacco leaf remains vital, its enzymatic systems continue to work, and they "burn" sugars.

However, if the cellular life of the tobacco leaves is maintained for too long after harvesting, it leads to excessive depletion of reserves. This, in turn, causes intense chemical transformations that affect the substance of the leaves. These substance-depleted leaves have extremely poor flavors. This also occurs in the case of over-fermentation. Once the cells are dead, the physical process of water evaporation accelerates, and the chemical change slows down.

In addition to air drying (Air-Cured), there is also sun drying (Sun-Cured) among the natural methods.

Sun Drying - Sun Cured

In sun drying, the leaves are laid out in the sun and then placed in the shade after a short period. As with air drying, the tobacco leaves are placed in drying barns. This risky method usually results in a more intense color but also a loss of flavors. In terms of protein and sugar breakdown, this drying method falls between air drying and artificial leaf drying methods.

Artificial Drying Methods

There are various methods in this category, depending on the type of tobacco. These processes generally take place in drying houses, where temperature and humidity can be precisely measured and controlled.

Fire-Curing

An ancient method used to dry thick leaves with a high nicotine content. In this process, the leaves are hung in the drying barn and then exposed to smoke from hardwood fires. Fire-cured tobacco, also known as Kentucky tobacco, has a distinctive character of flavors that have come into contact with smoke.

Smoke Curing

In smoke curing, freshly harvested tobacco leaves are air-dried and then hung over a heat source (wood fire or special fire systems). The smoke penetrates the tobacco leaves and imparts a characteristic aroma to them.

Pile Curing

Pile curing is an intense drying process. The tobacco leaves are stacked in large piles, or "piles." Between the layers, leaves with different properties are placed to ensure uniform fermentation.

Barrel Curing

Barrel curing is similar to the aging of whiskey or rum, as the tobacco leaves are sealed in special barrels. The tobacco ferments anaerobically, meaning without oxygen.

Flue-Curing

In this method, leaves are hung in barns and dried with hot air. This results in a cigarette tobacco with a high sugar content and medium nicotine levels (Virginia tobaccos).

Fermentation Duration

The duration of fermentation depends on the desired flavor and intensity. A longer fermentation typically results in more complex flavors.

Success Factors for Tobacco Fermentation

Proper fermentation requires preparation, correct leaf arrangement, and controlled ventilation and temperature.

Conclusion

Cigars can cater to a wide range of flavors, which is mainly due to the drying and fermentation processes.

Frequently Asked Questions

Can tobacco be dried in an oven?

Tobacco should not be dried in an oven, as temperature and humidity cannot be carefully regulated there.

Does the tobacco fermentation process need to be repeated?

A single fermentation is usually sufficient, but some manufacturers ferment tobacco multiple times for more intense flavors.

How much nicotine is in the cigar after fermentation?

During fermentation, tobacco loses nicotine. The amount varies depending on the tobacco type and method.

What is the sick period of a cigar?

The sick period is the phase when a cigar is not yet smokeable after rolling because the leaves must still bond together.