Why Are Natural-Processed Coffee Beans Sweeter?

For coffee lovers, do you know that coffee cherries need to be processed to remove the pulp, outer skin, and parchment layer to obtain green coffee beans? The processing method (such as natural/dry processing) affects the flavor of the coffee beans because certain chemicals from the fermented pulp seep into the beans, and different environments also influence the condition of the beans.

The most well-known processing methods are natural processing and washed processing:

• Washed processing produces beans with stable quality, a clean taste, and a brighter acidity.
• Natural processing, on the other hand, results in sweeter beans with more fruity notes.

How does this happen?

Let’s quickly review natural processing and washed processing.

Because coffee cherries have skin, pulp, mucilage, and parchment, it’s not easy to simply use machines to extract the beans directly. As a result, people have developed various methods to obtain the beans. The natural method is the oldest: the coffee cherries are dried in the sun for several weeks, turned regularly, and once dried, it becomes easier to use a hulling machine to remove the outer layers and retrieve the beans.

In contrast, the washed method involves using machines to remove the skin and pulp first. The beans, still coated with mucilage, are then placed in water, where microorganisms consume the mucilage. After this process, the beans are washed again, dried in the sun, and finally hulled to remove the parchment and obtain the beans.

Why are naturally processed coffee beans sweeter and more fruity?

Analysis shows that naturally processed coffee beans contain more sucrose and fructose than washed beans. However, this isn’t because the sun drying or fermentation process creates more sugar. Instead, it’s because the washing process reduces the sugar content in the beans!

Why is that? Let’s start with how plants work. The role of seeds or beans is to find a suitable environment to germinate and grow into a new plant.

During the washed process, when the beans are soaked in water, they may mistakenly perceive the environment as ideal for germination. This triggers chemical changes within the beans, consuming some of their sugar. So, even if they don’t actually sprout, they still lose sugar.

If the sugar content doesn’t increase, why do naturally processed beans taste sweeter?

This is because the fermentation of the pulp produces aromatic compounds that seep into the beans. Among these, butyl butyrate helps people perceive more sweetness when drinking the coffee.

Additionally, the higher sugar content in green beans from natural processing can generate more floral and fruity notes during roasting.

Washed coffee beans have their own unique qualities!

At first glance, it might seem like washed beans are overshadowed by naturally processed beans. But that’s not the case! Because the washed process allows for better control, it consistently produces high-quality beans with the clean, elegant flavor profile they’re known for. In fact, washed beans often have more complex flavors! The process of consuming sugar during germination-like conditions produces amino acids, which can develop into layered aromas during roasting.