News 16 Aug 2018

About a Bean: The process

16 Aug 2018
#Coffee Beans

About a Bean: The process

Written by:
Dušan Matičič, head roaster at GOAT STORY

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There are a whole lot of factors that determine the taste of your special cup of coffee, culminating in the last pour a barista will make. But actually, the core flavor of a bean has been decided long ago, even before it was a bean-like we know it. In this blog post, we will see how the processing of coffee cherries affects the flavor in your cup.

So what does affect the flavor notes of a bean? It all starts with genetics. Different cultivars - Bourbon, Caturra, Castillo, and Gesha - each have their taste. Then there’s the elevation of the plant; higher up there is less oxygen in the air, which means a denser and more complex bean. We’ll write about cultivars and elevation in separate blog posts. Today, let’s focus on the transformation from the coffee cherry to the coffee bean. It is an important transformation that will quite often determine the character of a coffee bean.

Explore all GOAT STORY coffees HERE!

There are three most common methods for treating coffee cherries: Natural Process, Washed (wet) process, and Honey process (pulped natural). There is no general rule about the treatment of cherries and it will mostly depend on the region and seasonal weather.

Coffee beans - coffee cherries

 

Natural Process - Robust and in your face

This process is commonly known also as a “dry process” or “dry natural” does not need water. It is basically how you’d dry your cherries at home – when picked at optimal ripeness, the cherries are dried to a certain moisture level.

Let’s first see, how a coffee cherry looks: (usually) there are two seeds inside a cherry. Each seed is covered with a thin layer (mucilage) and the two are coupled together. The beans are covered with a thin layer of pulp and protected by a skin that wraps the pulp tightly.

During the natural process, the cherry is left intact, just allowing it to dry. That means that the seeds will pick up some of the characteristics of the sweet pulp and flavors from the skin. Only after a certain degree of drying, is the cherry broken apart in the milling stage that hulls the skin, pulp, and mucilage from the beans.

Natural processed coffees are dried on raised beds and mostly apply to African coffees, while this process is lately less common in other parts of the world. It’s a specific process that is mostly used because of the lack of water in a region, that doesn’t allow for a wet process.

The natural process can be risky. A faulty drying process can leave the coffee with strong unpleasant flavors that occur because of fermentation that happens in the cherry. But! Fermentation, if controlled well, can give an additional flavor dimension to the bean.

Natural processed coffee will give a fuller body and notes of citrus and lime acidity or even a strong berrylicious flavor.

Bottom line – a naturally processed bean can be spectacular if treated with care or total sh**, if there was too much of fermentation in the cherry (or if the cherry started to rot because of too high humidity). But it has a romantic feel to it, as this is the oldest coffee processing method.

Flavor profiles: Bold, rich bodied fruity flavors that are inherited from the cherry pulp and skin. Think citrus, berries, tropical fruit, bergamot, black tea, and chocolate. Very “obvious” flavors that are easy to distinguish even for the less trained coffee taster.

Common regions: Ethiopia, Brazil

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Washed Process - Crisp and delicate

When civilization met coffee, it created a process that makes the bean more predictable and (of course), producing a secure harvest, as the skin and pulp are removed from the bean immediately after harvest in the depulping process.

Cherries are tossed in a fermentation tank or wet mill, where the cherries pass a series of stations, where they get depulped and “bad” less dense cherries get skimmed from the pack, as they float on the water. The good cherries sink to the bottom and travel through the depulping device. Then the seeds land in a fermentation tank where they rest for up to three days.

As there is no influence from the skin and pulp, the bean will be cleaner in taste. It’s hard to say if it’s better or not compared to a naturally processed bean. It’s just that the flavors are pulled from the bean itself, with no taste influence from the cherry itself. A washed bean will have a different acidity, as it is developed in the fermentation tanks where the beans “interact” with what is left of the pulp. Farmers need to be cautious during fermentation, as too much of it can develop an unpleasant vinegary acidity, so pH levels need to be checked regularly to keep the acids smooth and citric.

The bottom line, a washed coffee will mostly have a delicate body and pronounced acidity with clear flavor notes. And it’s predictable and consistent, which has a great impact on the value of the coffee (especially when roasters don’t want to risk too much with their choice of beans).

Flavor profiles: A clean taste that showcases the flavors found in the bean. A well-balanced bean that screams complexity and has a subtle acidity. A cup of coffee that will be almost tea-like with notes of starfruit to dark chocolate, but very commonly floral notes are obvious.

Common regions: Latin America, Africa

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Honey/Pulped Natural process - Syrupy sweetness

This process is somewhat stuck in the middle between natural and washed. It will fit well the coffee lover that doesn’t mind for a crisp citric acidity of a washed coffee or a berry acidic explosion of a natural.

The honey process is a mix of the two – after harvest, the beans are depulped, but are not submerged in fermentation tanks, so the mucilage will dry with the seed. Depending on the amount of mucilage left, leaves a distinctive floor of the bean, ranging from black to yellow (the lighter the color, the less pulp was left on the bean).

What is left is a bean with a creamy body, acidity that is somewhat suppressed and with taste notes that quite often resemble - yes, you guessed it – honey. There are less fruity notes than in a natural processed coffee, as there is no influence from the skin.

Bottom line – a honey processed bean will be like a natural, but with suppressed extreme flavors (for instance, you will get some strawberry or raspberry notes, but never as extreme as blueberry that can prevail in a natural). On the citrusy side, you’ll probably never get a honey processed coffee that will have strong citrus acidity, rather that of a smooth orange.

Common Flavor Profiles
Smooth sweetness with notes of jam or sugar. A creamy, honey-like texture. Less acidity as a washed bean and less flavor explosion than a natural.

Common regions

Brazil, Central America

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Don’t forget!

There’s more to coffee than reading the label and checking for the process … taste your coffee and don’t limit yourself to a single process. There’s still a whole lot of experimenting in coffee processing, so let your senses determine what you like, not the label on the bag! Enjoy!