Coffee Bean Quality Standards: A Behind-the-Scenes Look at Coffee Production and Local Consumption Practices

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Understanding Coffee Varieties and Common Coffee Variants

There are over 500 species of coffee trees and 6,000 varieties, most of which are tropical trees and shrubs. There are four main coffee tree species in the world, but only two have significant commercial value and are widely cultivated. The coffee beans produced by these species are considered superior to those from other coffee tree species.

Fresh coffee cherries, from which raw coffee beans (seeds) containing parchment and pectin are extracted from the pulp.

The first type is Arabica beans. World-renowned coffees like Blue Mountain and Mocha are almost exclusively Arabica varieties. The other is Robusta, which originated in the Congo region of Africa. Different varieties of coffee beans have different flavors, but even coffee trees of the same variety produce beans with unique characteristics due to different soil, climate, and other environmental factors. The other two species are Liberica and Excelsa.

Biologically, coffee varieties can be divided into Arabica, Robusta, and Liberica. The main varieties consumed worldwide are Arabica and Robusta, while Liberica is often overlooked due to low production or poor quality.

Generally, Arabica is mainly used for single-origin or specialty coffee, while Robusta is used for instant coffee. Although Arabica can be classified as premium coffee and Robusta as secondary, this classification is not absolute—it's more appropriate to distinguish them based on personal taste preferences. From a flavor preference perspective, the United States and Japan tend to prefer milder coffee brewed from Arabica, while Europe favors espresso made from a blend of Arabica and Robusta.

Arabica: Coffee Beans with Better Flavor and Aroma

Arabica is a representative variety originating from Ethiopia, also produced in South Africa, Africa, and Asian countries, accounting for 70%-75% of global coffee production. Arabica has relatively weak resistance to pests and diseases, making high-altitude regions more suitable for cultivation. Arabica coffee beans grown at altitudes above 1,500 meters have the best quality.

This labor-intensive process produces high-quality coffee with balanced flavor and aroma, earning it certification as premium coffee beans, mainly used for single-origin or specialty coffee. The three famous coffee beans—Hawaii Kona, Jamaica Blue Mountain, and Yemen Mocha—belong to the Arabica variety. Arabica raw beans have a dark, narrow appearance and are hailed as the highest quality high-altitude Arabica variety, characterized by rich flavors including sweetness, acidity, and aroma.

Robusta: Strong Acidity with Intense Body

Robusta originates from the Congo region of Africa and accounts for 30% of global coffee production. The name "Robusta" means "robust," and indeed, this coffee tree not only has strong resistance to pests and diseases but can survive in any soil and even grow in the wild. Therefore, it can be cultivated in high-temperature regions, grows quickly, and is easy to cultivate, offering the advantage of low price. It is mainly used for blending or as the primary ingredient for instant coffee. Some Robusta varieties from India, Africa, and Brazil have strong acidity, high caffeine content, and a richer body.

As a very important variety in the coffee world, Robusta has made significant contributions to the commercial coffee sector. The value of Robusta is not to serve as a negative example to highlight how premium Arabica's flavor is—it holds an unshakable position in espresso blends. Italian blends often add small amounts of Robusta to enhance the body of coffee, producing espresso with richer crema.

When Espresso blends with milk, it presents a rich, full-bodied texture. Milk coffee becomes richer and more aromatic due to the complementary nature of Robusta and Arabica, with Robusta compensating for Arabica's body.

Recently, there has also been the Arabusta variety, a cross between Arabica varieties, with superior taste and aroma.

Robusta has a plump oval appearance, with raw beans showing light brown or yellowish-brown with grassy green and yellow luster.

Excelsa Coffee Variety

Excelsa is a variety discovered in 1904, originating from the Charlie River basin in Africa. The fruit is small, with high yield per plant, and it is particularly drought-resistant. The product has strong flavor and aroma, slightly bitter, and is rarely cultivated.

Typica Coffee Variety

Typica: The oldest native variety from Ethiopia, from which all Arabica varieties derive. Typica has bronze-colored top leaves, with oval or slender-pointed beans; elegant flavor, but weak constitution, poor disease resistance, and low fruit yield. Excellent estate beans like Jamaica Blue Mountain, Sumatra Mandheling, and Hawaii Kona all belong to Typica. The bronze-colored top leaves of Typica are one of its characteristics.

Typica raw beans have slightly upturned ends, oval in shape, and appear thin from the side. Even when cultivated at different altitudes, the thickness difference on the side of raw beans doesn't vary significantly.

Genetic Mutant—Typica Variants

Sumatra Mandheling - Typica Variant

Indonesia's main coffee producing regions include Sumatra Island, Java Island, and Sulawesi Island, with Sumatra's "Mandheling" being the most famous.

Mandheling is also called "Sumatra Coffee." Coffee from Lake Tawar in the north can be called Aceh Coffee or Lake Tawar Coffee, while the Lintong and Lake Toba regions can be called Mandheling.

Mandheling has a rich flavor with intense body and vibrant, lively character, neither astringent nor acidic, with body and bitterness fully expressed. The appearance of Mandheling coffee beans can be said to be the ugliest, but coffee enthusiasts say that the less attractive Sumatra coffee beans look, the better, richer, and smoother they taste.

Four types of Mandheling have been collected:

Gold Mandheling,

Horse-face Mandheling (Timtim Mandheling long berry) Sumatra Island, Mandehling Longberry, Timtim Belangele,

Lintong Mandheling Grade -1,

Emerald Mandheling (Sumatra Aceh Province)

Above: Gold Mandheling raw beans

Above: Horse-face Mandheling full natural processed raw beans, a hybrid of Arabica and Robusta, called Timor, known as Timtim variety in Indonesia.

TimTim—

That is Timor Hybrid, translated as East Timor Hybrid, a hybrid of Arabica and Robusta. The familiar Catimor was created by further hybridization with this variety.

Tim Tim—Horse-face Mandheling longberry

Tim Tim is a bean from Indonesia. Due to its long shape, many people call it horse-face bean, while others call it long Mandheling. Actually, Tim Tim is not a pure variety but a natural hybrid of Arabica and Robusta coffee trees. This variety was discovered on Timor Island in the 1940s and was cultivated due to its natural disease resistance. In the Americas, this variety is called Hybrido de Timor, abbreviated as Tim Tim, while in Indonesia, it's also called Bor Bor.

Above: Lintong Mandheling G1, although Grade 1, still cannot escape the high defect rate characteristic of Indonesian beans, with about 8% defective beans

Above: Emerald Mandheling (Sumatra Aceh Province), 19 screen+, raw beans are green, full, and crystal clear, like emeralds

Blue Mountain - Typica Variant

Blue Mountain: Globally popular, the hard-to-find Blue Mountain comes from the Typica family.

Jamaica's coffee history can be traced back to the 18th century when the British introduced coffee trees to Jamaica, planting coffee in the Blue Mountains. This is further divided into high-altitude Jamaica Blue Mountain Coffee, Jamaica High Mountain Coffee, and Jamaica Coffee, with different grades determining different prices.

Jamaica Blue Mountain Coffee (Jamaica Blue Mountain Coffee) is further divided into four grades based on quality, from top to bottom: NO.1, NO.2, NO.3, and PB (PB stands for Peaberry). According to CIB standards, only coffee grown above 666 meters altitude can be called Jamaica Blue Mountain Coffee.

Jamaica High Mountain Coffee (Jamaica High Mountain Supreme Coffee Beans) produced below 666 meters in the Blue Mountain region is called High Mountain Coffee. It's second only to Blue Mountain Coffee in quality and is called the brother variety of Blue Mountain Coffee by industry insiders. Due to the extremely limited production of Jamaica Blue Mountain Coffee, Jamaica High Mountain Coffee is your best choice if you want to taste Jamaican-flavored coffee.

Jamaica Coffee (Jamaica Prime Coffee Beans). Coffee grown outside the Blue Mountain range is called Jamaica Coffee. Originally, Chinese coffee professionals had a misconception that only coffee grown in the Blue Mountain region above 1800 meters altitude could be called Blue Mountain Coffee. In fact, on the 1800+ meter mountain crown of the Blue Mountains, there is only one estate—Amber, owned by a Chinese descendant whose surname is Lyn, with ancestral roots in Guangdong, China. This estate has only 30 hectares of land with very limited production. Blue Mountain Coffee is mainly distributed across five mountain areas: John Crow, St. John's Peak, Mossman's Peak, High Peak, and Blue Mountain Peak.

Hawaii Kona - Typica Variant

Kona: Although cultivated at altitudes of just a few hundred meters, Kona from Hawaii's Big Island enjoys gentle sea breezes and fertile volcanic soil, possessing exceptionally clean acidity and sweetness. Compared to the higher altitude Blue Mountain, it's arguably superior.

Maragogype - Typica Variant

Maragogype, a mutant of Typica, with very large, long, slightly twisted fruits, and plants with long internodes and large leaves. Relatively low yield.

First discovered in 1870 in the Maragogype producing area of Bahia state, northeastern Brazil. The beans are at least three times larger than regular Arabica, hence the name. Elephant beans have poor flavor at low altitudes but better flavor at high altitudes, with mild acidity and pleasant sweet aroma. (Left in the image above is elephant bean)

Above right is elephant bean

Pacamara - Typica Variant

Pacamara: A hybrid of Pacas and Maragogype, with beans second only to Maragogype in size. It's an excellent variety developed in El Salvador in the 1950s, with good cupping scores in recent years.

Kent - Typica Variant

Kent: A Typica hybrid discovered in India, with high yield and strong disease resistance, but has never achieved good cupping scores.

Bourbon Coffee Variety

Bourbon: An early variant (pre-coffee history) of Typica after being transplanted to Yemen, with beans changing from slender-pointed to round. In 1715, France transplanted Yemen's round-bean Mocha to Bourbon Island on the east coast of Africa (renamed Reunion Island after the French Revolution), and it was named Bourbon. Bourbon round beans were introduced to Brazil and Central and South America in 1727. In 1732, Britain transplanted Yemen Mocha to St. Helena Island (later where Napoleon was imprisoned), also Bourbon round beans. Bourbon is often victorious in American specialty coffee cuppings.

Bourbon is a sub-variety produced by Typica mutation, one of the oldest existing coffee varieties along with Typica. When green fruits mature, they turn bright red.

Genetic Mutants—Bourbon Variants

Red Bourbon - Bourbon Variant

After a general coffee tree flowers and fruits, the color change of coffee cherries is: green > light yellow > light orange > mature red > darker red when overripe, hence some call it [Red Bourbon]. In fact, Red Bourbon is what we generally call Bourbon variety. Bourbon grown at high altitudes usually has better aroma, brighter acidity, and even flavors similar to red wine.

Simply put, Bourbon is a coffee tree variety belonging to a branch of Arabica, generally bearing red fruits, called Red Bourbon. Besides this, there are also Yellow Bourbon and Orange Bourbon. Yellow Bourbon has relatively lower yield but better quality.

Yellow Bourbon - Bourbon Variant

Yellow Bourbon is a hybrid of Bourbon with other varieties. Due to its lower yield and less resistance to wind and rain, it hasn't been widely cultivated. However, when grown in high-altitude areas, it exhibits excellent flavor characteristics and has become more common in recent years. Yellow Bourbon, with yellow fruits when ripe, was first discovered in Brazil and now mainly grows in Brazil. It's generally believed to be a mutation resulting from hybridization between red-fruited Bourbon and a yellow-fruited Typica variant called "Amerelo de Botocatu."

Flavor characteristics: Sweet and smooth fruit sweetness, distinct nutty flavors, balanced and gentle acidity, weak and clean bitterness, with rich chocolate aroma and nutty flavors, bright and refreshing taste.

Pink Bourbon - Bourbon Variant

Pink Bourbon, as the name suggests, has romantic pink coffee cherries when ripe. It's a very rare new variety, cultivated by hybridizing Red Bourbon and Yellow Bourbon. The reason Pink Bourbon is considered rare is mainly because maintaining this beautiful pink color is extremely difficult—sometimes orange Bourbon is harvested because the final color of coffee cherries is determined by recessive genes in pollen grains. Among the selected pollen grains for hybridization, there are both yellow genes favoring Yellow Bourbon and red genes favoring Red Bourbon, all of which are recessive and easily interfere with each other.

Currently, Pink Bourbon can be found in Colombia and Guatemala. Taking this batch of Pink Bourbon as an example, with about 1,800 coffee trees, each tree produces about 1.8kg of fresh fruit per harvest season. After pulp removal processing, about 0.36kg of coffee beans is obtained. In a normal harvest season, this coffee's production is less than 650kg.

Flavor characteristics: Sweet orange, sugarcane sweetness, pleasant juiciness, small tomato

Bourbon Pointu - Bourbon Variant

Bourbon Pointu: Discovered on Bourbon Island in 1810, with beans changing from round to pointed shape, and caffeine content only half of regular varieties; but low yield and weak constitution, extremely precious (mostly cultivated in laboratories).

Bourbon Pointu has two other names: Laurina and Leroy, but neither is as famous as Bourbon Pointu. It's called Pointu Bourbon because the beans are narrow and pointed at both ends, while the original Bourbon (some call it Round Bourbon) has shorter beans with slightly oval contours.

Due to its good flavor and low caffeine content (less affecting sleep), Bourbon Pointu was popular worldwide as early as the 18th century. Many celebrities, like King Louis XV and novelist Balzac, were its "fans." During the two hundred years from the 18th to 19th century, Bourbon Pointu was widely cultivated on Bourbon Island, reaching a peak annual output of 4,000 metric tons in 1800. However, a series of disasters followed—hurricanes, fire ants, leaf rust disease—leading to gradually decreasing cultivation. Finally, in 1942, the last batch shipped back to France was only a pitiful 200 kilograms, and since then, Bourbon Pointu disappeared without a trace, not even mentioned in official documents. After the 1950s, Reunion Island no longer cultivated coffee, and the island's agriculture completely转向ed to other crops like sugarcane. Coffee and Reunion Island were no longer connected, and Bourbon Pointu was officially recognized by the coffee industry as "extinct."

Given that this bean disappeared for half a century and only reappeared 8 years ago, in the international market, Bourbon Pointu from its origin La Reunion Island sells for over 500 yuan per 100 grams. Afterward, Colombia also began cultivating this bean, and only Camilo Merizalde, source of beans for multiple WBC champions, dared to take on the transplantation of this bean. Therefore, this coffee bean, with global annual production of only a few tons, commands a high price.

Archived flavor description: Bright acidity, blueberry and vanilla notes, velvet-like smoothness

SL28, SL34 - Bourbon Variants

Kenya's "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 the past century, they have adapted to Kenya's high-phosphate soil, nurturing Kenya's characteristic acidic aroma spirits. Top Kenyan coffees all come from these two varieties, but when transplanted elsewhere, they lose their distinctive character.

Kenyan coffee grades are divided into seven levels based on bean size, and six levels based on taste, from top to bottom. Kenya's best coffee grade is Peaberry (PB), followed by AA++, AA+, AA, AB, etc., in sequence. Premium coffee has bright luster, delicious taste, and slight wine aroma. In terms of flavor, "Kenya AA" is particularly well-regarded.

Grading by bean size:

Kenya's best coffee grade is Peaberry (PB), followed by AA, AB, etc., in sequence.

PB (Peaberry): This is a grading for small round beans. This refers to coffee cherries that grow only one bean instead of the usual two.

AA: This is a more common grade with larger coffee beans, size above 18 screen or 7.22 millimeters. These beans usually command the highest prices.

AB: This grade combines A (size 16 screen or 6.80 millimeters) and B (size 15 screen or 6.20 millimeters); accounting for about 30% of Kenya's annual coffee production.

Caturra - Bourbon Variant

Caturra: A single-gene mutant of Bourbon discovered in Brazil in the 1950s, with better yield capacity and disease resistance than Bourbon. The plants are shorter, making harvesting convenient. Unfortunately, it encounters the same problem as Bourbon—bearing fruit one year and resting the next. Its flavor is comparable to or slightly inferior to Bourbon beans.

However, it has stronger adaptability, can be densely planted, and doesn't need shade trees—thriving even when directly exposed to strong sunlight, hence it's also called "Sun Coffee."

Caturra is suitable for low altitudes of 700 meters to high altitudes of 1700 meters, but the higher the altitude, the better the flavor, though yield decreases relatively. There are also yellow Caturra variants in Central and South America, but their reputation doesn't match Yellow Bourbon.

Catuai - Bourbon Variant

Catuai: A hybrid of Mundo Novo and Caturra, essentially a second-generation hybrid. It inherits Caturra's advantage of short plant height and also compensates for Arabica's weakness of fragile fruit. The fruit sets firmly and doesn't easily fall off in strong winds. The biggest drawback is that its overall flavor is somewhat monotonous compared to Caturra.

Catuai also comes in red and yellow fruit varieties, with the red fruit variety winning awards more often than yellow. Catuai, Caturra, Mundo Novo, and Bourbon are Brazil's four main coffee varieties.

Pacas - Bourbon Variant

Pacas: A Bourbon variant discovered in El Salvador. In 1935, Salvadoran coffee farmer "Don Alberto Pacas" selected high-yield San Raymond Bourbon varieties for cultivation on his farm. In 1956, his coffee trees produced more fruit than trees of the same type. University of Florida professor "Dr. William Cogwill" determined that this was a genetic mutation of Bourbon and named it "Pacas."

Pacas has high yield and excellent quality, quite popular in Central America. Currently, 68% of El Salvador's coffee belongs to Bourbon varieties, with Pacas accounting for 29%. Similar to Brazil's Caturra and Costa Rica's Villa Sarchi. Today, Pacas constitutes about 25% of El Salvador's coffee production, with high yield and has always been popular. It produces coffee with high sweetness, similar to Bourbon, but with brighter acidity.

Pacas tree seedlings

Villa Sarchi - Bourbon Variant

Villa Sarchi: A Bourbon variant first discovered in Costa Rica in the 1960s, frequently appearing on cupping excellence lists in recent years—a dark horse with promising prospects. This is a rare variety cultivated through hybridization of Red Bourbon trees. Resistant to strong winds, prefers high-altitude environments, with excellent acidity and various complex fruit notes, high sweetness, bright and delicate citrus acidity with deeper raisin and nut aromas, high complexity and excellent balance.

Also a dwarf Bourbon, discovered in the Sarchi village of western Costa Rica's valleys, suitable for high-altitude organic cultivation, with lively fruit acidity and distinct caramel flavor.

Hybrid Variants

Mundo Novo

A natural hybrid of Bourbon and Sumatra Typica, first discovered in Brazil. High yield, resistant to pests and diseases, widely planted in Brazil in the 1950s, hailed as the new hope of Brazil's coffee industry; but the trees are tall, making harvesting difficult.

Nicaragua Java

Java variety from Nicaragua, now a rare long-bean variety. First successfully cultivated in Nicaragua by the Lemon Tree Estate. The Java variety originates from the Typica system. Java's Typica once suffered a severe leaf rust outbreak, nearly wiping out Java's Typica. The Lemon Tree Estate unintentionally obtained a bag of seeds, and after planting and growing seedlings, they took young plants to experts for identification, only to realize it was the Java variety. In 2007, Lemon Tree first participated in COE with this variety, surprisingly winning second place in Nicaragua's COE that year, with a bidding price even exceeding that year's champion.

In Indonesia, the main coffee variety in the West Java producing region is S795 (also called Jember). This variety was spread to the island by the Jember Coffee Research Center, so locals call it S-795. It's a hybrid of Typica mutant Kent and S-288, with strong resistance to leaf rust disease and prominent sweetness.

Maracaturra

A hybrid variety of Maragogype and Caturra cultivated in Guatemala (Maragogype × Caturra), receiving higher recognition after winning the 2009 Nicaragua COE championship. It combines Maragogype's rich fruit flavors with Caturra's elegant acidity, high body, full floral aroma, and high sweetness.

Arabica Variety - Geisha

Geisha: A derivative variety of the Typica family, exported from Geisha Mountain in southern Ethiopia in 1931 (Geisha has the same pronunciation as Japanese "geisha"), remaining obscure in many countries. It was transplanted to Panama in the 1960s and only began frequently winning cupping competitions starting in 2005.

| Geisha, also called Gesha

Geisha has the same pronunciation as Japanese "geisha," hence it's also called Geisha coffee; because the tree variety is taller than general coffee trees, it was originally planted in a small area within the estate and used as a windbreak.

| Geisha is a variety

First, Geisha seeds were discovered in the Geisha forest of Ethiopia in 1931 and later sent to Kenya's Coffee Research Institute. In 1936, it was introduced to Uganda and Tanzania; in 1953, Costa Rica introduced it.

| Red Label, Green Label, Blue Label

Only Geisha from Hacienda La Esmeralda has [Red Label, Green Label, Blue Label] distinctions:

Red Label (Special-Geisha): Brings together the top batches from Esmeralda estates, all grown at altitudes above 1600 meters (even above 1900 meters), with cupping scores above 90 points;

Green Label (Private Collection-Geisha): Geishas from different plots within Esmeralda estates, grown at altitudes of 1600-1800 meters;

Blue Label (Geisha1500): Geishas from Esmeralda estates, grown at altitudes above 1500 meters;

| Geisha's unique floral and fruit aroma

Among many coffees, floral aroma and intense tropical fruit sweetness are consistent characteristics of Geisha.

Arabica and Robusta Hybrids (Interspecific Hybrid)

Timor

Timor: A natural hybrid variety discovered in East Timor, an island nation at the eastern end of the Nusa Tenggara archipelago, with 44 chromosomes, closer to Arabica; but with plain flavor, low acidity, lacking distinctive characteristics, often used in Taiwan as a blending bean to reduce costs. However, East Timor also has high-altitude pure Typica with washed processing. Before purchasing, be sure to clarify whether it's a hybrid variety or pure Typica washed beans—their quality differs significantly, with the former being plain and unremarkable, while the latter is stunningly impressive.

Catimor

Catimor: In 1959, Portuguese crossed Brazilian Caturra with Timor hybrid, cultivating the second-generation hybrid Catimor with super strong disease resistance and yield capacity. However, its flavor is relatively poor, and it's currently an important commercial variety. To improve Catimor's poor cupping reputation, botanists from various countries have recently returned to crossing Arabica with Catimor multiple times, attempting to reduce the Robusta lineage.

Icatu

Icatu: A variety improved through multiple generations of hybridization in Brazil, once ranking in Brazil's "Cup of Excellence" top ten. In the past, Arabusta, a hybrid of Arabica and Robusta, improved yield and disease resistance but coffee flavor remained poor. Scientists then multi-generation hybridized Arabusta with Arabica varieties like Caturra, Mundo Novo, and Bourbon, gradually reducing the undesirable taste of Robusta while enhancing Arabica's aroma and richness, thus creating the excellent multi-generation hybrid variety—Icatu.

Ruiru 11

Ruiru 11: A hybrid variety developed by Kenya in 1985 that prioritizes yield over quality. A hybrid of Arabica and Robusta, it still cannot be considered specialty coffee. Therefore, many suppliers specializing in fresh-roasted specialty coffee, such as fresh, do not carry these varieties. However, many imported specialty coffee suppliers mix this hybrid into blends to reduce costs. From the genetic mutants mentioned above (whether natural or research products), their flavor is greatly influenced by specific regional conditions.

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