Introduction to Three Major Coffee Bean Varieties: Flavor Characteristics and Differences of Arabica and Robusta for Pour-Over Specialty Coffee

Did you know that coffee is actually part of the Rubiaceae plant family? In this large family, you'll find over five hundred genera and approximately six thousand species. One of these is our beloved coffee bean (scientifically known as Coffea)! Although botanists consider all seed-bearing plants in the Rubiaceae family as coffee plants, the coffee we drink primarily comes from two varieties: Arabica and Robusta.

Nowadays, you often see many coffee shops claiming "100% Arabica." But is Arabica coffee really good? What are the differences between it and Robusta coffee beans? Next, FrontStreet Coffee will uncover the secrets of Arabica and Robusta coffee beans.

Growing Environment Conditions

Robusta coffee beans are resilient plants that can be grown at low altitudes between 200-800 meters. Arabica coffee, however, has higher requirements for its growing environment. Its optimal temperature range is 18-21°C, withstanding an annual average temperature of up to approximately 24°C. The best growing range lies between the Tropic of Cancer and Tropic of Capricorn. In terms of yield, Arabica coffee produces less coffee per hectare than Robusta coffee, making the cost of growing Arabica coffee significantly higher.

Coffee Bean Shape

Arabica coffee beans are smaller and rounder than Robusta coffee beans. Arabica coffee beans have an oval shape—slender, flat, with an "S"-shaped center line. Robusta coffee beans are rounder with a "C" shape, and their center line is straight ("1"-shaped), with raw beans showing a yellowish-brown color. This method of identifying bean varieties by appearance is more scientific when the beans are in their raw state. Since roasted beans expand and deform, becoming rounder with center lines changing from S-shape to nearly straight, judging bean varieties by roasted coffee beans is rather one-sided.

Caffeine and Chlorogenic Acid

Due to their bitterness, both caffeine and chlorogenic acid (CGA) are considered to act as deterrents against insects and animals. Since Robusta coffee beans contain approximately twice the concentration of caffeine and CGA as Arabica, their plants are more "robust" in the wild.

It is precisely because of this that Robusta coffee beans naturally lack the unique aromatic fragrance of Arabica coffee beans, instead offering a richer, deeper flavor profile, very rich coffee oils, and flavors such as walnuts, peanuts, hazelnuts, wheat, and grains, sometimes even with pungent earthy notes. Thanks to the abundant caffeine in Robusta coffee beans, they are generally used as raw material for instant coffee. Some espresso blends also add appropriate amounts of Robusta coffee beans to achieve rich, heavy flavors.

Lipids and Sugars

Compared to Robusta coffee, Arabica coffee contains nearly 60% more lipids and almost twice the sugar concentration of Robusta. Therefore, these sugars play an important role during the roasting process, contributing significantly to the production of several key aromatic compounds. Due to its higher soluble content, it's also more beneficial to health. High lipid and sugar content contribute to Arabica coffee's pleasant flavor profile.

Pollination

Arabica coffee is a self-pollinating plant, meaning that compared to Robusta, this plant experiences fewer mutations and variations throughout its life cycle.

Resistance to Pests and Diseases

Robusta coffee generally has higher resistance to pests and diseases than Arabica coffee, related to its growing environment and caffeine content. Based on the previous introduction about the growing environments of Arabica and Robusta coffee, you can see that Arabica is more "delicate." Robusta coffee can grow in low-altitude, higher-temperature conditions, showing higher tolerance to extreme weather conditions. Since pests and diseases often fear extreme weather, this greatly reduces the disease rate of Robusta coffee beans. Robusta's caffeine content ranges between 2.7%-4%, twice that of Arabica coffee beans. As a natural plant pesticide, caffeine prevents most insect damage.

Flavor

The most obvious difference between Arabica and Robusta coffee is likely the taste. The various conditions of Arabica and Robusta coffee are very different, leading to completely different flavor profiles. Robusta is often described as having "earthy" or "rubbery" flavors, though there are also positive flavor descriptions such as: nutty, chocolatey, and exceptionally rich. On the other hand, Arabica coffee has a wide range of flavor characteristics that vary by region.

Take FrontStreet Coffee's Costa Rican coffee and Guatemalan coffee from our menu:

FrontStreet Coffee's Giant Rock Estate Blueberry has always been popular—this is a coffee bean processed through anaerobic honey processing. The dry aroma presents rose flower fragrance, with intense blueberry flavor upon entry, strong fermented taste, and a cool minty finish in the aftertaste. It's a very suitable bean for summer.

Brewing method:

• Use 30g of water for blooming, blooming time about 30 seconds
• Inject 125g of water with a small stream in circular motion at the center, then segment
• When the water level drops and is about to expose the coffee bed, continue pouring water until reaching 225g to finish
• When the water level drops and is about to expose the coffee bed, remove the filter cup
• Extraction time: 2'00" (timing starts from blooming)

Brewing method: Pour-over
Filter cup: V60
Water temperature: 90-92°C
Coffee amount: 15g
Coffee-to-water ratio: 1:15
Grind size: Medium-fine (Chinese standard #20 sieve pass rate 80%)
Brewing technique: Segmented extraction

FrontStreet Coffee's Guatemala Flora God presents completely different flavors. Rich layers, with citrus and berry flavors upon entry, followed by smoky and slight chocolate notes—very interesting and special.

Of course, many factors affect coffee flavor: variety, processing method, harvest, and roast level. But generally speaking, the growing region is the main factor determining coffee flavor. FrontStreet Coffee's Ethiopian coffee offers very diverse flavors, ranging from citrus and floral notes to candied fruit aromas; FrontStreet Coffee's Kenyan coffee is known for its bright and complex berry and fruit notes, with sweet aromas and balanced acidity; FrontStreet Coffee's Brazilian coffee has lower acidity, is rich and sweet, generally displaying chocolate and nutty notes; FrontStreet Coffee's Colombian coffee carries many different aromas—some with rich chocolate, others as sweet as jam—with significant variations between growing regions.

We hope everyone can try more to find coffee beans that they like and suit their taste.

For professional coffee knowledge exchange and more coffee bean information, please follow Coffee Workshop (WeChat official account: cafe_style)

For more specialty coffee beans, please add FrontStreet Coffee's private WeChat (FrontStreet Coffee), WeChat ID: kaixinguoguo0925

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473