Basic methods for processing coffee beans

The method of processing coffee beans has a significant impact on the formation of the final characteristics of coffee drinks. 

The process of processing coffee beans covers all steps of collecting coffee cherries, their maturation and removal of coffee beans from the cherry. 

For this reason, we distinguish the following methods:

• Neutral process –

In this method, the harvested coffee cherries are left to dry naturally.

In this method, all coffee cherries go through a manual inspection, which carefully removes all those that are damaged, immature or with any visible defects.

Unlike the wet method of treating cherries, this method removes all unwanted materials such as twigs and stones by hand, and in the presence of mud, it is removed by leaving the cherries floating in a small amount of water to wash it.

As with other methods, the coffee cherries are then dried, with the difference that during this process the coffee beans are not removed from the skin of the cherry.

Since coffee beans are not separated from the protective shell of the cherry during the whole drying process,

• Semi-washed process  –

a hybrid process that combines the characteristics of myths and natural processes. 

Here, the skin of the coffee cherry is removed mechanically, and the coffee beans with the mucus adhering to them are stored for a period of 24 hours before being subjected to washing and actual drying.

• Washed process  –

This includes several stages:

• • picking ready-made coffee cherries
  • washing the cherries – this helps to remove all unwanted materials such as mud and stones.
  • Remove coffee beans from the cherry by removing the fruit pulp and the red shell of the cherry. In most cases, the fruit pulp together with the remnants of the coffee cherry shells is recycled and used to fertilize the coffee beans.
  • After removing the coffee beans from the cherries, they are left to ferment in special fermentation cans in order to carry out a series of natural chemical reactions to emphasize the taste characteristics of coffee beans after roasting. During fermentation, the beans are washed again to remove any unwanted material on them. In this way, the moisture in the respective coffee beans reaches a level of approximately 57%.
  • in the last stage of drying the moisture in the coffee bean decreases below 12.5%
• Pulped Natural / Honey process –

In this process, balanced and sweet coffees are obtained.

They take the best of the wet and natural processing of coffee beans.

Coffee beans are far cleaner than those processed naturally and have much lower acidity than wet beans.

In Honey processing, the protective mucus around the coffee bean is preserved by less washing the bean, and during the fermentation process itself, the greyish skin on the bean is not removed.

As the mucus on the bean is sweet due to the high sugar content, coffees subjected to this type of treatment are distinguished by their sweetness and honey characteristics.

It would be interesting to note the fact that the Honey process can only be applied in countries

• • The Honey process itself can be of several types, namely:
    • white / yеllow honey  – in these methods of processing the coffee beans during the wet wash a small amount of mucus is left to cover the coffee beans and therefore the sweetness of the coffee is weaker.
    • red, gold and black honey  – the main difference in these three types of coffee bean processing is expressed in the amount of light and drying time. Higher humidity and slower processing from black honey coffee, which requires the drying process to be in shady places. Red honey is made at lower humidity, but in slightly brighter places compared to grains subjected to black honey treatment, while gold honey is used in sunny and maximally low humidity conditions.

In general, it can be said that  black honey  coffees maximize their potential fruit in the form of espresso drinks, while   white / yellow honey  coffees in the form of filter coffee.

• Moonsoned process 

In this process, the collected raw and sun-dried coffee beans are left under the influence and action of monsoon rains and winds for a period of three to four months (June-September).

As a result of this effect, coffee beans change some of their original characteristics. In general, these changes are expressed in the reduction of the initial acidity of raw coffee beans, which during the period of atmospheric exposure swell and increase significantly in size.

As a result, the aromatic profile of the coffee is strengthened and the formation of a practically neutral pH profile is achieved

Regardless of the chosen process of coffee bean processing, the methods of their drying can be generally classified as follows:

• Method of natural drying under the influence of sunlight – here the coffee beans are placed on brick or concrete pedestal beds, and when such are not available – on specially made beds of fine mesh. Drying usually takes 8-10 days depending on humidity and temperature. After the palpation treatment, the coffee is dried on a substrate, as in the wet process.
• Mechanical drying method – this method uses hot air drying machines. Usually, this method of drying is used when the goal is faster processing of large quantities of coffee beans.
• Combined method – in this method the coffee beans are dried by first drying the beans in the sun and then drying them with a mechanical dryer.