What Are the Common Varieties of Specialty Coffee Beans and Why Does Coffee Taste Sour - Is It Due to Brewing Methods?

FrontStreet Coffee - Introduction to Specialty Coffee Varieties

"Carefully select the most suitable varieties, cultivated at the altitude, climate, and soil conditions most conducive to coffee flavor development. Washed and natural processing, selecting flawless premium green beans, delivered to customers with zero defects during transportation. Through the masterful craftsmanship of roasters, bringing out the richest regional flavors. Then, using recognized standard extraction methods to obtain delicious coffee."

The regional flavors mentioned here simply refer to the differences in soil, varieties, climate, and water and soil conditions that create different coffee flavors around the world. This is also the soul of specialty coffee.

Typica

The most ancient native variety from Ethiopia, and the ancestor of all Arabica varieties. Typica has bronze-colored young leaves and oval or slender pointed beans. It has an elegant flavor but a weak constitution, poor disease resistance, and low fruit yield. Excellent estate beans such as Jamaica Blue Mountain, Sumatra Mandheling, and Hawaii Kona all belong to the Typica family.

Bourbon

A variant of Typica after it was transplanted to Yemen in early times, with the bean shape changing from slender pointed to round. In 1715, France transplanted the round beans from Yemen's Mocha to Bourbon Island off the east coast of Africa (renamed Reunion Island after the French Revolution), and the variety took that name. The round Bourbon beans were passed to Brazil and Central and South America in 1727, and in 1732 Britain transplanted Yemen's Mocha to St. Helena Island (later where Napoleon was exiled), which were also round Bourbon beans. Bourbon is the consistent winner in American specialty coffee cupping competitions.

Genetic Mutant - Bourbon Pointu

Discovered on Bourbon Island in 1810, with beans changing from round to pointed shape and a caffeine content only half the normal level. It has a low yield and a weak constitution, however, which makes it extremely precious and mostly cultivated in laboratories.

Maragogype (Elephant Bean)

The most famous variant of Typica, first discovered in 1870 in the Maragogype coffee-producing region of Bahia state in northeastern Brazil. The beans are at least three times larger than regular Arabica beans, hence the name. Maragogype has poor flavor at low altitudes, but better flavor at high altitudes, with mild acidity and a pleasant sweet aroma.

Geisha

A derivative variety belonging to the Typica family, exported in 1931 from Mount Geisha in southern Ethiopia (Geisha has the same pronunciation as the Japanese word for a traditional entertainer). It remained unknown in many countries until it was transplanted to Panama in the 1960s, and it only began to win cupping competitions frequently starting in 2005.

Kenya "SL28" and "SL34"

Direct descendants of Bourbon, selected and cultivated by French and British missionaries and researchers in Kenya in the early 20th century. Over a century they have adapted to Kenya's high-phosphate soil, nurturing Kenya's characteristic acidic aroma. Top-tier Kenyan coffees all come from these two varieties, but when transplanted elsewhere they lose their characteristic flavor.

Bourbon Amarello (Yellow Bourbon)

A unique Bourbon variant from São Paulo state, Brazil. Its coffee cherries do not turn red when ripe but stay orange-yellow. It was later discovered that other Bourbon derivative varieties in the region also have yellowing fruit skins.

Caturra

A single-gene variant of Bourbon discovered in Brazil in the 1950s. Its growth ability and disease resistance are better than Bourbon, and it does not require shade trees. The flavor is comparable to Bourbon or slightly inferior.

Some friends ask FrontStreet Coffee why coffee is acidic. Because coffee is originally a fruit, coffee beans all carry fruit acidity, and gentle acidity is the good acidity of specialty coffee.

Knowledge Extension

Arabica has many subspecies, all derived from Ethiopia's most ancient Typica and Yemen's Bourbon after being transplanted to Central and South America or Asia, where they varied and diverged.

FrontStreet Coffee Recommendation

Variety is easiest to taste in a cup that leans on Typica's descendants, and FrontStreet Coffee's PWN Golden Mandheling is a solid example from Sumatra. Graded G1 and screened from beans 18 mesh and above, with three hand-sorts leaving fewer than 3 defects per 300g sample, it is roasted medium-dark for dark chocolate, caramel, herbal, earthy, and woody notes with low acidity and a full body. Brew it as a pour-over with 15g of coffee and a 1:15 ratio at 87-88°C, ground to a coarse-sugar texture, pouring 30ml, then 100ml, then 95ml.