Everything you need to know about; arabica, robusta, liberica and excelsa, the main 4 different types of coffee beans, explained.

Coffee beans are found within the cherry of certain coffea plants. Coffea arabica, coffea canephora (known as robusta) and coffea liberica are species of coffee plant which all originate from the rubiaceae flower and produce 99% of the different types of coffee beans we cultivate.

So far the rubiaceae family contains over 120 different species of coffea plant; but because of low caffeine content, small yields and low economic value, the vast majority of beans produced by these other species (and subspecies) are excluded when we consider what the different types of coffee beans are.

Here we’ll explain everything you need to know about the 4 main types of coffee beans.

What Are The 4 Different Types Of Coffee Beans?

Within the coffee-lover community it’s claimed there are 4 different types of coffee beans, arabica, robusta, liberica and excelsa. In coffee-science however, Excelsa is subject to debate since it was reclassified in 2006 as a subspecies of coffea liberica. Despite this controversy it is still very much considered one of the main types of the coffee beans.

So let’s begin to break down these top 4 types.

Arabica Coffee Beans (Coffea Arabica)

Arabica is the most popular type of coffee beans and make up over 60% of the world’s current coffee production and Ethiopia (the origin) still claims to have the widest variety of this species. They are highly sought after in the coffee industry because of the sweet delicate fruit tones found commonly in these beans. Coffea arabica are relatively small plants reaching only around 3-4 meters which makes them easy to care for and when the cherries are ripe they will fall to the ground unless collected. 

Despite the high graded coffee harvested from these plants they are prone to disease, require regular pruning as well as pest removal. Arabica coffee is less acidic and actually contains 50% less caffeine (~1.61 g/100 g) than robusta coffee beans.

  • Appearance: They are a golden brown color and the central crack found is curved; they are also usually a little larger in size and a longer, oval shape.
  • Growing Conditions: High altitudes between 900-2000+ meters above sea level (and increasing) produce the best beans and it is suggested a steady flow of (1500-2500mm) rainfall is also ideal.
  • Taste: Subtle sweet and fruity flavor notes can be detected since the beans have low acidity (~5/10).
  • Yield: First flowering after 3-5 years coffea arabica has a low yield, maturing into cherries and then ripening in 9 month cycles.

Robusta Coffee Beans (Coffea Robusta)

Robusta beans come from the plant scientifically known as coffea canephora and are said to have a hard, sometimes bitter, quality. They make up around 30 to 40% of the coffee we produce and is in fact, easier to grow than its rival Arabica. 

A reason robusta is grown less globally is because it reaches hard to manage heights of around 10-12 meters and unlike arabica the cherries do not fall once ripe – meaning it requires more maintenance. However it has a high caffeine content (~2.26g per 100g) and is far more disease resistant; as well as producing a 2x higher yield than the other types of coffea plant. 

Although they do not compare to some of the amazing arabicas now available, robustas grown in high altitudes similarly create higher quality beans. The best robusta beans will have a chocolate and hazelnut flavor profile.

  • Appearance: Robusta tend to be a little dull in appearance with flat brown matt finish and a straight central crack; as well as being smaller and rounded in size and shape.
  • Growing Conditions: Best grown between 0-900 meters (3,000ft) above sea level and getting frequent heavy (2000-3000mm) rainfall. 
  • Taste: Normally slightly more bitter or even woody due its high acidity (~8/10) the best robusta beans have a chocolate and hazelnut taste to them.
  • Yield: Producing a high yield, they flower after 3-5 years, mature into cherries which ripen every 10-11 months.

Liberica Coffee Beans (Coffea Liberica)

Liberica represents less than 2% of the coffee produced worldwide but is a favorite in the Philippines. They are usually the most bitter in taste but are described as “woody”, with a floral and fruity scent. The raw seed has a slight yellow hue and the beans a unique and large shape. 

The size seems unsurprising when you see the 20 meters high coffea liberica plant these beans come from, but it does not correlate with caffeine content and they contain the lowest amount of the 3 main species (~1.23 g/100 g). Also they’re more susceptible to coffee rust which has devastated many coffee plantations.

Excelsa Coffee Beans

Excelsa is a bit of a pressure point in the coffee community as many consider it to be a species of coffea plant in its own right due to its unique flavor profile. Described as having fruity tones and a popcorn taste it is technically now categorized as a subspecies of liberica since they share similarities in their tall (15 meter+), tree-like structure.

This doesn’t deter us from including Excelsa when discussing the different types of coffee beans however as they are, unlike liberica, resistant to disease and pests. Something which is quite uncommon given their low caffeine content (~0.86/100g). 

Low numbers like these as well as difficulties farming mean Excelsa coffee beans are mostly consumed mostly by the local communities that grow them and account for less than 8% of the coffee we cultivate.

Blends, Hybrids & Varietals

Blends began by baristas taking different types of coffee beans that were pre-processed and mixing them together. Then they’d be packaged as signature blends that combine different flavor profiles. This can keep costs low by letting quality coffee be diluted with cheaper beans. 

Blends are separate to subspecies which may sometimes be referred to as varietals and can occur naturally or may be manufactured. As well, it is common for coffea plants to be cross-bred to combine the unique flavors of each plant, called ‘crosses’ and ‘hybrids’. The Cup of Excellence competition where cultivators can show off their latest creations is held every year and often influences what appears on our shelves.

You might come across various varieties when buying coffee, check the packaging and see if yours shows up on the list below:

  • Acaia (Sumatra + Bourbon cross)
  • Arabusta (C. Arabica + C. Robusta hybrid)
  • Bourbon (C. Arabica)
  • Catuai (Mundo Novo + Caturra cross)
  • Devamachy (C. Arabica + C. Robusta hybrid)
  • Geisha (C. Arabica)
  • Heirloom (C. Arabica)
  • Icatu (Bourbon + C. Robusta + Mundo Novo hybrid)
  • Kona (Typica)
  • Maracaturra (Maragogype + Caturra cross)
  • Mocha/Moka (Bourbon)
  • Mundo Novo (Sumatra + Bourbon cross)
  • Pacamara (Pacas + Maragogype cross)
  • Rasuna (Catimor + Typica hybrid)
  • Typica (C. Arabica)

Where Do Coffee Beans Grow?

The coffea plants on which all 4 main types of coffee beans are found on; grow white flowers and bunches of red cherries. The cherries are then harvested and processed to remove the outer layers of skin and mucilage and extract the bean inside ready for roasting.

Different types of coffee beans grow better in certain areas of the world. Liberica and Excelsa originated in West Africa but along with Robusta are most commonly grown around Southeast Asia. 

Overall, high altitudes and regular rainfall tend to produce the best quality coffee beans.

  • Ethiopia – Is considered the origin of coffee and the answer to the question ‘where do coffee beans come from?’ as it was where the first arabica plant originates from.
  • Brazil – Is the biggest producer of coffee beans in the world, mostly growing Arabica beans.

Processing Different Types Of Coffee Beans

The methods used when processing different types of coffee beans depends on the manufacturer. The convenience and cost may play a part in many companies’ choice but it really can make or break your brew.

Luckily for us, with the development of new technology that can sort cherries by ripeness, it is easier than ever for manufacturers to increase quality standards and evenness at each step. 

Here are the 2 most common ways to process different types of coffee beans:

  • Wet process – Both methods of wet processing start by soaking the cherries in water and pulping them to remove the outer layers. They may be washed again and left to ferment before then being left to dry for 4 to 12 days.
  • Dry process – During the dry process the fruit are not pulped in any way or washed. Instead the whole cherry is left to dry in the sun in a raised bed then periodically racked to avoid rot.

Following the wet or dry processes, coffee beans go through a dry mill. During this phase the remaining skin and parchment that are covering the coffee bean is removed. Then when only green seed is left they are sorted using density tables and optical sensors before being packaged, sold.

The final roasting process is what changes these green seeds into the brown beans we are used to seeing and calling coffee.

Buying The Best Types Of Coffee Beans

‘Single-source’ and ‘single-origin’ coffee grounds are more popular today than blends as they sell the story of a dedicated farmer and the feeling of the fresh farmland on which the coffee beans have grown. 

Beware however as these terms do not always specifically refer to coming from a single farm and can still be used in the context of different types of coffee beans grown within the same country. 

Look out for labels like ‘100% arabica’ to taste the sweet fruity tones of these high quality coffee beans more clearly.