Coffee & Tea 101 | It Starts with Great Coffee

Have you ever sipped an espresso and wondered what made it so delicious? You don't have to be a coffee geek (like us!) to be curious about your espresso's journey from bean to barista.

In this article, you'll find information on:

 

Plant Varieties

It Starts with Great CoffeeLet's begin with the plant itself. Two main varieties of the coffee plant are grown today: Coffea arabica (known as Arabica) and Coffea canephora (known as Robusta).

Arabica originated in Ethiopia, is typically grown in higher altitudes and accounts for 75-80% of the world's production. Robusta, on the other hand, is a lowland coffee species that originated in West Africa. It features greater pest resistance and a generally heartier plant, which results in higher overall yields -- but its high caffeine content gives it a intensely bitter and inferior taste. Some very carefully grown and processed Robustas can be found in premium espresso blends, however, as they can improve the crema and body. Additionally, human-initiated cross-breeding of Arabica and Robusta, which attempt to blend the low caffeine content and smoother taste of C. arabica with the heartiness and disease resistance of C. canephora, have resulted in new varietals which are highly adaptable, hearty and commonly used in commercial coffee plantations. 

Since C. arabica accounts for the majority of coffee available, we're going to concentrate on the two main cultivars in this variety: C. arabica cultivar Arabica (includes var. typica, often referred to as Typica) and C. arabica var. bourbon.

Varietal Name Description
 Typica Descended from the first coffee trees European settlers planted in Indonesia and the Americas, this is the standard cultivar from which many others originate. It features a conical shape with a main vertical trunk and secondary verticals that grow at a slight slant. While it has a very low production and is not particularly resistant to disease, it has an excellent cup quality.
 Bourbon Bourbon originated on the French colony of Bourbon (now La Reunion) and was taken to South America and East Africa by the French. It produces 20-30% more coffee than Typica, but less coffee than most cultivars, and is often cultivated in higher mountain regions throughout Central and South America. Its shape is less conical than Typica, it has more secondary branches, the angles between the secondary branches and the main stem are smaller and the branch points on the main stem are closely spaced. With leaves that are broad & wavy on the edges, the fruit is relatively small and matures quickly. Bourbon produces a more mellow cup than Typica.
 Mundo Novo First found in Brazil, this is a natural hybrid between Typica and Bourbon. It is strong, resistant to disease, has a high production, but matures slightly later than other cultivars. This varietal is very adaptable to higher altitude cultivation. Along with Caturra and Cauai, Mundo Novo produce lighter bodied and more acidic coffees than pure Bourbons.
 Caturra Also discovered in Brazil, this is a mutation of Bourbon that features high production and good quality, but requires extensive care and fertilization. Short, compact and with a thick core, the leaves are more round and shiny, but the fruit looks similar to the Bourbon.
 Catuai This high yielding plant is a cross between Mundo Novo and Caturra, originally from Brazil. A relatively short plant with branches forming a 45 degree angle with the trunk, this varietal's fruit doesn't easily fall off the branch, so it is favorable in areas with strong winds or rain. It is characterized by either yellow or red cherries (named Catuai-amarelo and Catuai-vermelho, respectively).
 Pache comum First observed on the El Brito farm in Guatamala, this varietal is a mutation of Typica and features a smooth or flat cup. 
 Pache colis Found on a farm with Caturra and Pache comum in Mataquescuintla, Guatamala, Pache colis features very large fruits and roughly textured leaves. 
 Catimor Created in Portugal 1959, this cross between Caturra and Hibrido de Timor (a natural hybrid of Arabica and Robusta) is extremely resistant to coffee rust. With high production and yields equal to or greater than other commercial cultivars, this varietal matures early and is often utilized in instant coffee products such as Nestle. Catimor accounts for nearly 70% of the plants currently grown in China and while there is no noticeable difference in taste if grown in lower elevations, plants grown higher than 4,000 feet result in a significantly degraded cup quality in comparison to Bourbon, Caturra and Catuai.
 Kent Derived from old stock Indian varieties initially planted during the Moghul Empire, Kent was spread by British planters in Africa and India. It's often used for its high yield and resistance to coffee rust.
 Maragogype A Typica-mutation discovered in Brazil, this plant is large and taller than either Bourbon or Typica. Production is low, but it produces huge beans with a light and nutty cup. Currently grown in Central and South America. 
 Pacamara This varietal is a recent cross-breed between Maragogype and Caturra, producing a similarly nutty, but brighter, cup than straight Maragogypes. 
 Blue Mountain Blue Mountain is a famous cultivar favored for its resistance to the coffee berry disease and ability to thrive in high altitudes. Grown in Jamaica and now in Kona, Hawaii, this cultivar cannot adapt to all climates and still maintain its high quality flavor profile. 

 

Growing & Harvesting

Your perfect cup of coffee begins its journey as a ripening cherry in the high altitude, sub-tropical coffee fields of Southeast Asia, Central or South America, the Caribbean or Africa. The mountainous and tropical climate of these regions provides an ideal environment for cultivating coffee plants until their cherries ripen from light green to a pale pink or bright red. Once ripened, the cherries are harvested by hand or machinery and then transported to a processing plant, where they're sorted by ripeness and density and processed according to the target flavor the plantation seeks to achieve. 

The bean's essential flavor has a lot to do with how it's treated after it's harvested and before it's roasted. There are several ways to process coffee and the method used by the plantation is largely driven by their climate and the type of variety they've chosen to cultivate.

Dry Process
or
Natural Method
Dry-processing is the oldest and simplest method, requiring less machinery and generally performed on plantations located in regions with limited rainfall and limitless sunshine (such as Ethiopia, Yemen, Indonesia and Brazil). The cherries are laid out on patios or wire mesh tables in the sun, then turned or raked regularly for about 2 to 3 weeks, or until evenly dried. Coffee processed in this manner is generally heavy-bodied, sweet, smooth and complex. Often, coffee that is dry processed is referred to as 'unwashed'. Because the fruit breaks down on the bean itself, natural processed coffees retain more sugar and oil which can contribute to a more chocolatey and fruity flavor.
Wet Process Wet processing is relatively new and involves sorting and pulping the cherries within high pressure water tanks, then removing the layer surrounding the bean (called mucilage) through fermentation. The beans are then laid out to dry or dried mechanically until their moisture content has been reduced from 60% to 11-12%. Wet processed coffee tastes cleaner, brighter and fruitier. Wet Process coffee is often referred to as 'washed'.
Pulped Natural This method involves pulping the cherries using the wet process method, without the fermentation stage to remove the mucilage. Pulped natural processing was made famous by Brazilian plantations because their climate's low humidity allows for rapid drying of the bean without fermenting the sweet mucilage. Taste-wise, pulped natural coffee is a hybrid of dry and wet processing: While its full-body is similar to dry processed coffees, it retains the acidity of wet processed coffee, although it is often sweeter. Coffees that are Pulped Natural are often called 'semi-washed'. The process referred to as 'Honeyed' is very similary to Pulped Natural processing.

Regardless of the method used, once the beans have dried, a sample is taken for roasting and cupping in order to determine the overall quality of the harvest. 

 

Roasting

Coffee BeansWhile your coffee's essential flavor is largely determined by the specific plant varietal and the processing procedure used back at the plantation, roasting your beans accentuates, amplifies or augments the aroma, acidity and other attributes. 

Each coffee company achieves their distinctive taste through their unique bean blend and roasting procedure, but the general process is as follows:

Stage Description
One: Endothermic The green beans absorb heat, slowly drying to a yellow color and giving off the aroma of toast or popcorn.
Two: First Crack The beans double in size, become light brown in color and lose about 5% of their weight.
Three: Pyrolysis Color changes from light brown to medium brown and the beans lose about 13% of their weight. The chemical process that occurs here is called pyrolysis, which is characterized by a change in the bean's chemical composition and a release of CO2.
Four: Second Crack After a short endothermic period, the beans release heat (exothermic), resulting in a medium-dark brown, accompanied by an oily sheen and a much quicker pop than the 'First Crack' stage.

Many connoisseurs advise against roasting well into the 'Second Crack' because aromatic compounds can be stripped off and then the bean's outer oils are more prone to oxidization. The American trend is to roast to a dark black with a bright and shiny surface -- largely because this roast hides poor blending, dirty machinery and stale coffee. 

The coffee's flavor will change depending upon the roast degree; the perfect roast will bring out certain nuances that are favorable to amplify. 

Tastes by Region

Now that you're versed in the agricultural and processing practices of the coffee industry, what does it all mean? From selecting a plant varietal to harvesting to roasting, every aspect of the coffee world is tailored around one principle: How will it taste? 

You may have noticed geographical designations on coffee you've purchased in the past; becoming familiar with these regional trends can help you determine which coffee bean tastes the best to you.

Central America

Mexico Notable Mexican coffees include Oaxaca Pluma and Alta Pluma, which are light bodied with a milk chocolate flavor and have the exceptional ability to carry these flavors into darker roasts.

Nayarita beans processed using natural fermentation have a fruity, tropical flavor.
Guatemala

Guatemalan coffees come from two notable regions, which differ greatly in taste and style:

Antigua - Heavier body than most other beans from this part of the world, Antiguan beans are spicy, smoky and can take darker roasts without degrading in flavor.

Huehuetenango - These beans are delightfully floral, with a delicate, buttery flavor.

Costa Rica The Terrazu region produces a bean with powerful sweet citrus & nut flavors, resulting in a heavier bodied brew than many other beans from this region.
Nicaragua Bourbons from this region can have a variety of middle flavors such as pear or vanilla, with roasts bringing out tastes reminiscent of pie crust or chocolate. These beans are generally milder and less acidic than most beans from Central America.
El Salvador Similar in flavor to the beans coming out of Nicaragua, El Salvador is producing espresso-grade beans utilizing the pulped natural processing method.

 

South America

Colombia Colombian coffees are considered to be 'classic cup' coffees, with medium body and acid. Some are of very high quality and can occasionally be deliciously surprising.
Brazil While much of the coffee coming out of Brazil is considered to be of poor quality, you shouldn't write off the whole region completely. Great Brazilian beans are low in acidity and feature a creamy body, mild taste and notes of cherry, sassafras and milk chocolate.
Peru Given Peru's terrain, it should be no surprise that their coffee plantations are of high altitude. This elevation contributes to an acidic quality in the coffee, and poor examples from this area can be thin and sour. While good samples also feature a high acidity, they balance the taste with a rich, sweet caramel roast flavor.
Bolivia Bolivia is just getting into the coffee growing business, and so far they have been producing some very fine, medium bodied coffees -- similar to what is produced in Columbia.

 

Islands

Jamaica, Blue Mountain Mellow and sweet, this coffee can produce the quintessential 'classic cup'.
Hawaii, Kona An iteration of Blue Mountain, Kona coffee also features the 'classic cup' flavor and features sweet fruit & vanilla notes.
Puerto Rico, Haiti, Cuba & Santo Domingo With smoky sweet peat and molasses flavors, it's no wonder coffee coming out of the Caribbean is highly valued by Italian espresso blenders.
St Helene & Galapagos Reminiscent of the heirloom Ethopian Yrgacheffe and Sidamos varieties, these coffees feature a floral flavor.
Australia While Australia was in the coffee business more than a century ago, high labor costs prompted many plantations to throw in the towel -- until mechanical harvesting significantly improved the agricultural economics in the 1980's. Since they're relatively new on the scene, Australian coffee's quality is still being assessed. It's a comparatively small industry internationally, so it is unlikely that you'll see much of it out on the import market. If you do and get a chance to taste, let us know what you think!

 

East Africa & Arabia

Kenya Kenyan coffee is humorously famous for coming in three basic flavors: Citrus, black currant and horsehair (!). Exceptional Kenyan beans will feature a delicious blend of citrus and black currant in a single cup -- plus a little spice, a little sweetness and even some hints of wine. Just try to avoid the horsehair.
Ethiopia

Many varieties of coffee come from Ethiopia, but these regions are particularly spectacular:

Harar - These dry processed coffees result in complex cups renowned for espresso blends. Famous for notes of blueberry, coffee from this region also features chocolate, apricot, leather, a hint of wine and even some gamey flavors.

Yrgacheffe - A potent floral aroma, delicate citrus and green tea flavors characterize coffee from this region. Exceptional blends also feature a sweetness and middle fruit notes that balance the heady flowers.

Sidamo - Fruity and floral, with some blueberry and tangerine notes.

Tanzania, Rwanda & Zimbabwe These are similar to Kenyan beans, but the acidity and fruit notes are more understated and often balanced by cedar flavors.
Yemen  Dry processed like Harar coffee, exemplary beans from this region can be swimmingly complex -- even approaching the effect of well aged wine or brandy.
Burundi & Uganda Unfortunately, crops from this region can vary greatly in quality from season to season: Sometimes, their low acid, heavy body cups feature vanilla and chocolate roast flavors -- even resembling a 'Super-Java' in taste; other seasons, however, the quality can be quite poor, so find out more about the coffee before you buy.

 

Indonesia

Java This island's name is synonymous with coffee because it was the first coffee region controlled by Europeans. Beans from this region are considered to be a 'classic cup', with a very heavy body and low acidity. Extremely heavy body, almost no acidity and an intense woody roast taste appear when this coffee is aged.
Sumatra

Mandeling - These heavy bodied, low acidity coffees are dry processed and feature a sweet mushroom or earthy flavor. If dark roasted, exceptional beans can have chocolate-molasses notes.

Other notable regions, such as Gayoland and Aceh, produce wet and semi-wet processed coffees with more acidity and fewer deep flavors than Mandhelings. Quality can vary significantly -- good crops can be plummy and sweet, while bad crops are somewhat dry and acerbic.

Sulawesi Toraja (f. Celebes Kalossi)

Featuring a 'classic cup' like Java, this semi-wet processed coffee also features dark fruit and exotic spice flavors. Chocolate notes are common when roasted.
Papua New Guinea Coffees from this island can significantly vary in flavor: Great quality beans feature a fruitier & lighter body than beans from Sulawesi and take a deliciously exotic twist on the 'classic cup' taste. Watch out, though: Bad beans are often described as reminiscent of beef broth. Ugh.
Bali Balinese beans are similar to those (in both good and bad) from Papua New Guinea. The Japanese love them, however, because the translucent emerald beans process flawlessly -- resulting in a expensive price tag.

 

India

India was the first region outside of Arabia to cultivate coffee and their long history with the bean means they have processing down to a fine art. Exceptional grade beans are spicy, with hints of tropical fruits. One method of aging, called 'Monsooned', results in a low acidity, very heavy bodied cup with intense woody and loamy flavors. Italian blenders prefer Indian coffees over Indonesian for espresso blends and their use in the US is just beginning.

 

The Science Behind the Magic

Never thought you'd read about coffee in the manner most people describe a fine wine or a delicious artisan cheese? Taste is a complex sensory process that is driven, in part, by aromatics. Aside from coffee's sweet, salty, bitter or sour attributes, its scent chemically informs us of a variety of subtle tastes and essences. But how does this seed from a little cherry suddenly take on spicy, buttery or caramel-like flavors? 

Aroma is perceived in one of two ways: It's either sensed nasally (when you put your nose into your coffee cup and inhale deeply) or retro nasally (when the coffee is either in your mouth or has been swallowed and aromatic compounds drift up the nasal passage). These compounds are responsible for the differing aromas of specialty coffee -- the number of which is currently over 800 and it's increasing every year! For comparison, wine has about 100 different compounds that influence its flavor.

How one perceives aroma is based on the concentration and odor threshold of the compound, and even though over 800 compounds have been identified in coffee, it's likely that a relatively small subgroup of compounds that are similar in both high concentration and low odor threshold combine to form the scent we think of as 'coffee'. 

These compounds engage in complex chemical reactions, the by-product of which is a specific scent that combines with the scent of a simultaneously occurring chemical reaction to create a unique aromatic compound.

Compound Group Description
Furans The predominant group of compounds, furans have a caramel-like odor that is likely the result of the pyrolysis of sugars during the roasting or brewing processes.
Pyrazines The second most abundant class of compounds in coffee, pyrazines bring cereal, cracker, walnut, roasted or toast-like notes.
Pyrolles Pyrroles are responsible for the sweet, caramel-like and mushroom-like scents in coffee.
Thiophens Due to a reaction between sulfur-containing amino acids and sugars, thiophens have a meaty aroma.

The next time you brew your favorite coffee, take a moment to breathe deeply and savor your coffee's unique aromatics; you might find it's difficult not to be impressed by the complex chemistry located in your tiny cup.