This text first appeared in the summer of 2020 as a trilogy on the blog section of Dutch coffee subscription service Roast. Since their operational take-over in the following year the(se) original texts, as well as all other 60+ monthly tasting reviews I wrote since April 2015, were taken down. Since Robusta is destined for the future I reckoned it to be nice, to translate and re-publish this trilogy (with minor editing) as a whole here. Have a good Read!
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Intro
The focus on quantity rather than quality can be traced back to the times of the 'first wave' of coffee mid last century, when we saw the rise of instant coffee and its significant use mostly dark roasted pre-ground coffee blends.
However, inspired by the 'second wave' and especially propelled forward by the current 'third wave', Arabica has amply proven that differentiation, focus and refinement of quality can lead to increased value for the entire chain, from producer to consumer. Since the past decade (the fourth wave?!) These developments have accelerated.
Robusta coffee is part of this, in order to become 'Fine / Premium Robusta' as much as possible: “a class of defect-free Robusta similar to Specialty Arabica, in which coffee presents unique and desirable characteristics as a result of an interaction between varieties, micro-climates in origin and accentuated by best cultivation and processing practices.”*
(*partly based on and inspired by Fine Robusta – Standards and Protocols booklet, The Coffee Quality Institute // G. Davies, Standart Magazine #18 // Conilon Coffee 3rd edition, Incaper.)
Appearance
The term 'Robusta' is actually the name of a widely grown variety of this species. It is a robust shrub or small tree with a shallow root system, but capable of growing up to 10 meters in height. The fruits are rounder than those of the average Arabica berry. The seeds, on the other hand, are mainly oval in shape. Robusta takes 1 to 2 months longer to grow from flower to ripe berry. Ripe berries usually remain on the tree for a very long time.
The identification -apart from the correct main name at all- is confusing, but two main forms are usually distinguished: 'Robusta' - the plant with more erect forms and the 'Nganda' - which forms more spread out in width. Other varieties have glorious names such as Apoata, Peridiana, Erecta, Gamé, Nemaya, Sankuru, Bukoba, Niaouli, Maclaudi, Laurenti, Petit, Indénié, Nana, Oka, CxR etc.
Robusta is grown in West and Central Africa, Southeast Asia and in some regions of Central and South America, such as Guatemala, Mexico, Nicaragua and in Brazil, where it is known as Conilon. In Costa Rica, the ban (!) on cultivating Robusta has been discussed and (fixed) revised for some time.
History
The first commercial cultivation of Robusta began exactly 150 years ago in the Democratic Republic of Congo using wild plant seeds collected on the banks of the Lomami River.
Botanists also discovered the same species ten years later in the Bukoba region of Tanzania. The 'Kouillou' (phonetically altered and transformed to ´Conilon´ in Brazil) breed was observed in 1880 by the French, more west, between Gabon and the mouth of the Congo River, mainly along the eponymous Kouillou River in present-day Congo-Brazzaville. Later the species was also found in Madagascar where it was cultivated on a large scale.
In 1895, the French botanist Louis Pierre described the material as 'Coffea canephora'. Two years later, the German Albert Froehner published a description of the species; According to him, in 1900 seeds of Coffea canephora from Congo were sent to the House of Horticulture of Jean Linden in Brussels, whose son Lucien marketed it under the name 'Coffea robusta'.
From here, seeds were sent to Java, where it achieved great success by being resistant to the rust disease. This positive momentum marked the beginning of large-scale cultivation of 'robusta' coffee in Indonesia. Hence the generalization of the name 'robusta' which, with an optimistic note, refers to 'robustness' and resistance to disease in equatorial climates.
The plant collection was further enriched with material from Gabon and Uganda. The robusta plants brought to India came from collections and selections from Indonesia, Uganda, Ghana, Mali and Ivory Coast. Subsequently, cultivation spread to other regions in Africa, Asia and South America (especially Brazil).
Taste
'Fine Robusta' coffee is known for lower levels of salt (producing a harsh taste) and higher levels of organic acids (producing a smooth, balanced taste). The "salt/acid" ratio is the relative balance between the salt sensations, mainly driven by the higher potassium levels of Robusta coffees as opposed to the normally lower levels of organic acids, especially citric acid (compared to Arabica).
This ratio is responsible for the pleasant and delicate taste derived from distinct acidity in Robusta coffees, which result from the presence of fruit acids and sugars. Lower levels of potassium or salty compounds that make robusta coffees taste coarse or harsh are absent in Fine Robusta. The discernible perception of a pleasant acidity is one of the striking taste differences between Fine and lower quality Robusta coffees.
The "bitter/sweet" ratio is the relative balance between these two sensations, with the optimal combination of low bitterness and high sweetness. Both bitter and sweet taste sensations are present in robusta coffees. The bitter component mainly comes from the caffeine and potassium levels, while the sweet component is derived from, among other things, fruit acids. Fine Robusta coffees have a low bitter and high sweet aspect in their taste, while commercial Robusta coffees usually have this reversed.
Commonly found fruity flavor notes in Fine Robusta include: cherry, black currant, raisin, raspberry, currant, dried fig, plum, and lemon. Nutty and spicy flavor notes can reveal themselves as: walnut, almond, malt, cloves, coriander and allspice. Sweetness presents itself as: molasses, syrup, caramel, honey and dark chocolate. Newer processing methods like honey, (carbonic) macerated or inoculated can generate several (tropical/stone-) fruit notes, like pineapple, coconut and mango, as well as praline, pine nuts and dark honey.
Arabica or Robusta?
Crosses between Arabica and Robusta are aimed at improving the former, by imparting disease resistance and potency from the latter. Grafting Arabica onto Robusta is one way: A part of one plant is attached to a part of the other plant, so that it lives and grows, as it were, on the strong shoulders of the wearer. Hybrid seeds can also be grown at an earlier stage by crossing the correct combinations of genes in laboratories.
In recent decades, many national coffee research institutes have already developed such new varieties, which are often encountered on a bag of coffee. Spontaneous, natural crossings have also occurred over the many years. The most famous examples of Arabica, with a hint of Robusta are: Catimor, Icatú, Catucaí, Marsellesa, Castillo, Colombia, Lempira, Tabí and Obatá.
Trivia
- Robusta contains at least twice as much caffeine as Arabica.
- Ho Chi Minh City in Vietnam, the largest producing country of Robusta coffee, has a statue honoring Louis Pierre, the first describer of the variety.
- Arabica is the love child of mother Coffea Eugenioides 💘 father Coffea Canephora. So "100% Arabica" on a package is even less significant than is generally assumed... 😉
- Vietnam, Brazil, Indonesia, India, Uganda and Ivory Coast are – in respective order – the largest producers of Robusta.
- Robusta beans have a greater density than most Arabica beans and are more resistant to heat, optimally up to 30 degrees Celsius.
- In addition, Robusta already thrives at lower altitudes, sometimes from 'only' 500 meters above sea level and it requires more rainfall, from two meters per year, where Arabica has that as an upper limit.
- Planting one hectare of Robusta produces about 40% more harvest than Arabica.
- Robusta is diploid and dependent on cross-pollination, which keeps it genetically diverse but makes identifying specific varieties more complicated. So Robusta is very similar to… humans 😃!
(Arabica is self-pollinating, which seems like a useful advantage. It does have a to remain genetically stable, but the resistance to external influences (diseases) is therefore only moderate.)
- On the scale of "Critically Endangered – Endangered – Vulnerable – Low Risk of Threat – Low Concern", Robusta falls under the latter category while Arabica is already classified under "Vulnerable". This is reflected in the worldwide production figures of both varieties; The ratio 30 years ago being still at 30 (R) vs. 70% (A), these figures are now at 40 vs. 60%. Around the year 2030, the ratio is expected to be fifty-fifty!
- Of the five majorly notorious, well-known coffee diseases, there is one that Arabica can handle in contrast to Robusta, namely the wilting disease (which is caused by a type of fungus).
