What is the effect of coffee treatment on flavor and aroma? How long does it take for coffee to ferment?

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Street Coffee introduces the evolution history of coffee treatment with raw beans-from the sun to washing:

At first, coffee fruits were harvested as long as they were laid in the sun until they were dried, which was the sun drying method. Very little water is used in the whole process. It is a way that can be operated by ordinary producers.

When the exocarp is peeled off, the producer is expected to shorten the drying time and reduce the mildew and other bad odors caused by damp rain in the sun process. But did not expect that the layer of colloid in the pericarp is more difficult to deal with. Therefore, I think of the method of removing gelatinous bodies with water, because gelatinous bodies are mainly composed of pectin and sugar and are easily dissolved in water. After removing the gelatin, the coffee beans are easy to dry and clean and easy to operate. The treatment has an effect on flavor and aroma because the changes in sugar in the flesh of coffee cherries treated with sun or honey change the chemical reaction of raw beans. These changes eventually affect the sweetness and alcohol thickness of the coffee.

Germination stage

The germination stage means that the coffee fruit is picked after it is ripe, which means that the seeds in the fruit are about to begin to germinate. Germination activates some polysaccharides enzymes, indicating that natural sugars are about to break down.

The enzyme activity of water-washed coffee is more than that of sun-treated coffee, and the aroma compounds and free sugars in raw beans are partially decomposed in the process of water-washing, which makes the taste of water-washed coffee beans more refreshing and less aroma compounds. the acidity will be more obvious.

Fermentation stage

During fermentation, microorganisms change proteins, carbohydrates and chlorogenic acid. Fermentation can have a great impact on the flavor, aroma and alcohol thickness of coffee, but the fermentation process needs to be carefully controlled. Excessive fermentation will produce too much acetic acid and phenolic compounds, which will make the final coffee bitter or sour.

Sun-cured coffee is sweeter than washed coffee because of the fermentation of sugar in the pulp. This is due to the fact that the pulp and pectin have been removed during washing, resulting in very little caffease content in washing. Sun-cured coffee will produce more aromatic compounds, not only sweet in the coffee, but also fruity, floral and caramel. In contrast, washed coffee tastes cleaner and is easy to drink with a specific coffee flavor.