Arabica's potential rivals

 Almost everyone who loves specialty coffee knows the three most common coffee species: Arabica, Robusta and Liberia.

The most popular and commonly consumed currently is Arabica. Almost everyone is coffee industry knows Arabica well and recognizes it for it’s quality. Personally, I am stand with the majority.

As a Q Grader, I had an unwavering loyalty to Arabica. I felt that only Arabica could produce the high quality aroma and flavor of specialty coffee. Granted, I have tried Robusta coffee from time to time, but still felt that it had no chance of joining the ranks of specialty coffee alongside Arabica.

However, the story between me and Robusta had only begun.

In July 2015, Torch Coffee Lab in Puer, Yunnan conducted the first R Grader course in mainland China.

At first, I simply wanted to get a better understanding of Robusta coffee, the species that accounts for about half of the world's coffee consumption. Why is the output so high and who would even enjoy drinking this lower grade product?

Bottle green: Robusta,

Light green: Robusta and Arabica

Yellow: Arabica

Although I did not personally like the taste of Robusta, my desire to learn more about coffee gave me the desire to understand and explore this branch of coffee.

To begin the experimental process, my coworkers and I drank Robusta from various origins for a whole week. When I drank the predictable bitterness of Robusta in the first cupping, I thought it was impossible to discuss these beans in terms of a specialty coffee standard.

This experiment only reinforced my prejudice against it; however, life is always full of surprises. As if God intended to tether my fate to Robusta, during one of the next cupping sessions, I tasted a coffee with a surprisingly high sweetness. It tasted as though someone had added a spoonful of honey right into the cup.

Everyone though there was a mistake and that someone had slipped an Arabica coffee into the cupping group. It was rich in flavor and full of floral aroma. The room was stunned upon finding out that the coffee on the table was actually a Robusta!

During that week of R grader course, we had fine Robusta coffee from around the world including Myanmar, Laos, Mexico, Uganda, and India. We found that Robusta coffee can not only be on a par with Arabica, but also has the potential to compete with higher quality Arabica coffees. My narrow mind was opened and enlightened with all the new possibilities!

This recent discovery is very exciting news for coffee culture. Because of Robusta's potential and own advantages, it is bound to play a decisive role in the specialty coffee industry in the future.

Due to the uncertainty of climate change, the typical environments that are suitable to grow Arabica are becoming fewer and far between. Robusta is more conducive to survival, and eventually it will play a more important and dependable role in the field of specialty coffee.

Robusta has a higher yield and contains more antioxidants than Arabica. It chemical make-up has nearly twice as much caffeine as Arabica, and is far more resistant to pests and diseases.

If you plan to work or are already working in the specialty coffee industry, mark my words, Robusta is in your future.

The Characteristics of Robusta

Genes are highly variant and resilient, and their genetic diversity is very broad. 

Chromosome: 22

Shallow-rooted but high yields.

Pollination is cross-pollination.

Takes 10-11 months for the fruit to grow from flowering to ripening. Flowering time is uncertain.

Bean Shape: round tip

Bean Color: grey to grey-blue

The optimum temperature is 20-26 ° C on average.

Best growing altitude: 100-900 meters worldwide, 800-1,200 meters Uganda, Congo and Tanzania wild varieties

The origins of Robusta are very diverse, in the inlands of West and Central African and in the East African highlands.

Varieties are naturally distributed in Côte d'Ivoire, Cameroon, Rwanda, South Sudan, Uganda, Northern Tanzania, Zaire, Northwest Agra, Congo and Gabon.

 Commercial coffee is distributed in the lowlands of Central and West Africa, the highlands of East Africa, Indonesia, Vietnam, India, Brazil, Ecuador, Guatemala and Mexico.

Antibodies against rust, fungi, insect pests and black fruit disease of coffee, but susceptible to vascular fungal diseases

Typical flavor characteristics: low aroma, low acidity, strong bitter taste, full-bodied, woody flavor, aftertaste with pyrolysis and spicy taste

Market

Market share is about 40%.

It is mainly used for blended espresso to increase body and produce thicker crema. We usually blend 5-15%, sometimes up to 25% of Robusta in total amount of roasted coffee.

Where do flavors come from?

When you first begin drinking coffee, more often than not the first taste impression to most our palette is bitter. We may occasionally taste acidity, but the floral and fruity flavors that coffee connoisseurs like to describe are confusing.

For people who know very little about coffee, they will think that the flavor notes describing the coffee are added flavor substances in drink. In fact, that is not the case. The magic of coffee is that it has thousands of different flavor profiles! So far, we’ve known more than 800 kinds of distinct tastes in coffee, and there are many more to be discovered.

So where do all the varying flavors of coffee come from?

Coffee is a crop similar the fruit and vegetable we eat everyday. Vegetables and fruits in one area have the same attributes, but there are some differences in taste, shape and variety when the environment is different. Once coffee is planted in the ground, it’s origin is the first factor to affect the flavor.

In a map of the world, we can see that most coffee agriculture is distributed between 25 degrees North and South latitude in Africa, Central America, South America, Asia and some island countries. According to the altitude and the climate and soil of each origin, coffee is susceptible to the influence of the environment in the process of coffee growth, which results in different tasting coffee.

coffee belt

On the other hand, the variety of coffee tree also determines the flavor of coffee. For example, in the coffee family tree pictured below, the three thickest branches are Robusta, Arabica and Liberia. These are the three main varieties of coffee at present.

Arabica and Robusta have the largest market share, but the difference is very obvious. It lies in the chemical composition of the two varieties.

We all know that coffee contains caffeine, which is a substance that exhilarates and energizes people. At the same time, caffeine is one of the sources of bitterness. Meanwhile, another substance in coffee is chlorogenic acid which provides acidity and bitter taste. Robusta contains more caffeine and chlorogenic acid than Arabica.

Moreover, Robusta coffee has less sucrose, which brings sweetness, than Arabica. Robusta usually has full body and more bitterness while Arabica has more complexity and higher-quality flavors.

Processing method of coffee is also an important factor on the flavor. The coffee we drink is actually the seeds of coffee fruits called coffee cherries. The parchment, mucilage, and pulp that the seed is surrounded by provide flavor substances for coffee seed.

The three basic processing methods of coffee are washed, natural and honey process.

Natural, as the most primitive processing method, is drying out fresh coffee cherries directly after harvesting. Flavor substances of the whole coffee fruit, i.e. pulp, mucilage and parchment, can be fully absorbed by the seed as well as fermented with many other microorganisms.

The results show that the natural processing produces more winey, berry-like, tropical fruit flavors with a higher sweetness.

Natural Processing

Honey process is to remove the pulp and keep mucilage layer of coffee for fermentation and drying. Coffee mucilage contains sugar and microorganisms which enhanced fermentation. Therefore, honey process highlights the sweetness and nutty flavor of the seed itself.

Honey Processing

Washed process differs from the former two in its richness and complexity. It usually has a clean, bright citrus flavor.

Washed Processing

This is due to the time before drying, pulp and mucilage of washed beans were removed. After the removal of external flavor-producing substances, only the internal flavor substances are left. So washed coffee represents clean and simple flavor characteristics.

Washed Processing

In each processing method, we eventually dry the coffee beans to 10-12% moisture content, within which the coffee embryo can remain active.

Once the embryo dies, the flavor substances in coffee will also be quickly lost. This is known as the old crop which has a distinct woody flavor.

There are two kinds of water-induced embryo death, one is that the water content is too low and the embryo is dry out. In this case, coffee beans accelerate staling.

Dead beans

Another case is that the water content is too high, the embryo is prone to mildew and death in the humid environment, and the subsequent impact is that coffee beans become dead beans, or moldy beans.

Moldy beans

Similarly, even well-dried coffee beans need to be stored in an appropriate storage environment.

Since coffee beans have very high adsorption, taints or excessive humidity in the storage environment can greatly affect the green beans. Therefore, when we store green beans, we should control the room temperature at 21℃-22℃ and relative humidity in a stable environment of 60% - 65%.

Good storage conditions also affect the flavor of coffee roasting.

The processing methods mentioned above are to change the flavor of coffee fruit through the external structure of the seed, while the roasting process is to present the flavor through the change of chemical substances inside the coffee seed.

From green to roasted beans, more than 800 flavor compounds in coffee have been noted after roasting.

In the process of roasting, organic acids and proteins in coffee beans, which affect the flavor, are constantly decomposing. The darker the roast, the less the retention of acids. Darker roast are known to have lower acidity and higher bitterer.

At the same time, when roasting Italian espresso coffee, it is very common to blend coffee in order to modulate the flavor of coffee.

At the end, the coffee flavor in our cup is adjusted by the barista through a variety of brewing methods, equipment, and skills.

As a coffee enthusiast, our expectation for coffee flavor is changing after every cup. And different people have different preferences. So, what kind of flavor do you like best in coffee?