Coffee Origin and Flavour: Growing and Processing

The short answer: According to the Deutscher Kaffeeverband (German Coffee Association), the flavour of an origin depends heavily on the growing region, much as with wine: altitude, temperature, rain, sun and soil. Processing (wet, dry or semi-dry) shapes it further. Studies show tendencies, such as more acidity from cool locations (Bertrand et al., 2012) and more body in natural than in washed coffee (Choi and Yoon, 2011). Which level weighs more is an open question. On the bag, these details are voluntary, whereas the best-before date is mandatory.

How to read the origin details on the bag

What a coffee bag says about growing and processing is there because the roaster chose to write it. The German coffee regulation (Kaffeeverordnung) governs designations such as decaffeinated or candied, but it contains no obligation to state growing country, altitude, processing, variety or roast date. Under the EU Food Information Regulation (LMIV), as the German Federal Ministry of Food and Agriculture summarises it, the country of origin only has to be named if buyers could be misled about the actual origin without it. All the more is revealed when someone gives a lot of detail. We recommend this order:

1. Check how narrowly the origin is defined. A continent is a blend, a country is a rough direction, and a region with municipalities is a trail you can follow. The reason: the site factors that the Coffee Association names for flavour depend on the individual location. In a study from Costa Rica, even east-facing slopes differed from other slopes (more on this below).
2. Look for a figure in metres. The word highland alone does not help. According to the Coffee Association, coffee from about 1,000 metres upwards is often called highland coffee, but the legislator has not so far defined the term, and the industry also has different approaches.
3. Read the processing: washed or lavado for wet, natural or unwashed for dry, honey, pulped natural or semi washed for semi-dry. According to the Coffee Association, the processing methods shape flavour (see the processing section below).
4. Look for the variety. Arabica is the species; Bourbon, Caturra or SL28 are varieties within that species. If the name is missing, the bean is not worse because of it, you simply know less.
5. Distinguish roast date from best-before date (MHD). The best-before date is mandatory and describes the period in which a food keeps its specific properties when handled correctly. It does not say when the coffee was roasted. A printed roast date is therefore the more precise information about age, if the roaster gives it voluntarily.
6. Take brewing recommendations for what they are: the manufacturer’s details, which you can start from, not measured values.

What altitude, climate and shade do to the bean

The Coffee Association counts altitude, temperature, rainfall, sun intensity and soil conditions among the site factors, but gives no ranking. Research gets closer to the matter when it separates individual factors. On La Réunion, Bertrand and colleagues (2012) examined coffee from 16 plots. Among the climate variables, the mean air temperature during seed development had the strongest effect on the sensory profile. Acidity, fruity character and aroma quality were typical of a cool climate, while high temperatures and plenty of sun went along with defects such as green or earthy notes. Altitude therefore works mainly through the coolness it brings.

In Costa Rica, Avelino and colleagues (2005) compared two altitude terroirs: Orosi at 1,020 to 1,250 metres and Santa María de Dota at 1,550 to 1,780 metres. In both, the tasters preferred coffee from higher altitude. East-facing slopes mostly produced better and more acidic drinks; on a scale up to 5, acidity reached 2.73 in Orosi against 2.36 on other slopes, and 3.64 against 3.28 in Dota. In Dota, acidity fell when yield rose. Orosi showed floral notes, Dota a chocolate note that became clearer at high altitude. Caffeine, trigonelline, fat, sucrose and chlorogenic acid, by contrast, were only weakly related to the sensory results.

A similar direction comes from Honduras. Decazy and colleagues (2003) evaluated 52 Arabica plots in six regions; the best coffees came from Olancho and El Paraíso. High altitude and annual rainfall below 1,500 millimetres favoured quality, and the suitable roasting time should be sought for each terroir.

There are two pieces of evidence for the explanation of slower ripening. In an Ethiopian study by Tolessa and colleagues (2017), the plots at high altitude, 1,950 to 2,100 metres, averaged 19.3 degrees, and those at medium altitude, 1,600 to 1,680 metres, 22.5 degrees. At high altitude, harvesting took place on average about 50 days later, and the beans became heavier with altitude. The authors see this as support for the assumption that low temperature slows ripening and fills the bean better. For shade, there is a measurement from Costa Rica: Vaast and colleagues (2006) compared full sun with 45 per cent shade in the Central Valley of Costa Rica. The shade cost 18 per cent of yield, delayed the ripening of the fruit flesh by up to a month, and improved the size, composition and beverage quality of the beans. The authors interpreted the higher sucrose, chlorogenic acid and trigonelline in the sun-grown beans as a sign of incomplete ripeness, which explains more bitterness and astringency.

Two studies from south-west Ethiopia show how closely altitude and shade are linked. In Worku and colleagues (2018), acidity rose with altitude only under shade, by 0.22 points per 100 metres; without shade the effect was absent. Sucrose increased with altitude, but clearly only in wet-processed beans (3.02 grams per kilogram per 100 metres against 0.36 with dry processing). The follow-up study of 2022 divided the locations into lowland below 1,550 metres, midland up to 1,900 metres and highland above that. In the highland, bean density was highest, while the share of large beans (screen 17 and larger) and the share of defective beans fell with altitude. Large beans are therefore not a feature of altitude.

How large all this is in points is put into perspective by the study of Tolessa and colleagues. Coffee from high altitude with open or medium shade and early to medium harvest had the better quality there. At high altitude, early rather than late harvest raised the share of the Q1 class (from 85 points) from 27 to 73 per cent; at medium altitude, harvest timing had no significant influence. The authors stress that scores shift only slightly with altitude, shade and harvest time, but in the borderline range they decide between Q1 and Q2. Our assessment: altitude is a tendency towards density and acidity that depends on shade, slope and yield, not a guarantee of a particular cup.

Altitude grades: every country draws its own limits

The abbreviations SHB and SHG appear on bags as if they were an international standard. They are not. The only compilation with a stated source that we found for Central America comes from the UN Economic Commission ECLAC (CEPAL) from 2002 and relies on the national coffee institutes. For Chiapas in Mexico there is an official standard. We did not find current limits from Anacafé (Guatemala) and IHCAFE (Honduras), and further figures circulate in the trade that cannot be traced back to any official source.

The lower limit of the top grade thus ranges from 1,000 metres in Chiapas to 1,480 metres in Guatemala. How much weight the top grade had is also stated by CEPAL: in Costa Rica, SHB made up 37.4 per cent of production and 48.5 per cent of exports, in Guatemala 37.8 and 45 per cent. In El Salvador, the top grade accounted for around 31 per cent of exports, in Honduras SHG for 20 per cent, while HG made up 69 per cent of production there.

Our assessment: an SHB or SHG on the bag only means something together with the country. If a figure in metres is given next to it, that is more informative than the abbreviation, and both values remain claims by the roaster or importer.

Kenya sorts by size, not by altitude

East African abbreviations work differently. Kenya’s 2019 coffee regulations set standard grades by bean size and density, sorted with screens and by air separation. Growing altitude or cup quality do not feature in them.

Dealer sites sometimes assign AA and AB to other screen numbers; for this guide, the regulations apply.

Washed, natural, honey: what happens during processing

Processing has to happen soon after harvest, because the cherries do not keep long and cannot be transported. The Coffee Association distinguishes three routes. Wet-processed Arabica from certain countries is called Milds in world trade (Colombian Milds, Other Milds); Robusta and Brazilian Natural are mostly dry-processed.

The dry method is the oldest. It is finished when the flesh on the outside is dry and firm and you can hear the beans when you shake them. Whether fermentation in the wet method runs under water or dry in the tank is left open by the brochure.

The Coffee Association places honey on the side of wet processing: both could develop a fine acidity. In the Korean espresso study, twelve trained assessors scored on a 15-centimetre line scale, and pulped natural lay between the other two. The dissolved solids (TDS) were highest in natural and lowest in washed. The origin and lot of the samples cannot be seen from the abstract. Our assessment: honey lies between washed and natural; the two sources give no more than that.

Why wet and dry taste different: metabolism in the seed

The common explanation is that with natural processing, sugar migrates from the flesh into the bean. This is not documented; research shows something different. Knopp, Bytof and Selmar (2006) processed Arabica of the Acaià variety in parallel by the wet and dry methods. Washed beans contained only small amounts of fructose and glucose, dry-processed ones clearly more. The comparison with untreated control samples showed the direction: with wet processing, the two sugars decreased, with dry processing they stayed the same or rose. Sucrose, the main sugar in green coffee, did not change significantly through processing. The authors see the cause in an active metabolism of the seed.

Selmar and colleagues (2006) followed this up. The differences remained even when identical starting material was processed in parallel by both methods, so they must arise in the bean itself. It could be shown that germination sets in within the seed during processing, recognisable from the markers isocitrate lyase and beta-tubulin. Bytof and colleagues (2007) found the highest germination activity two days after the start of wet processing and only about a week after the start of dry processing.

According to the Coffee Association, fermentation is the conversion of organic matter into acids, gases or other substances, driven by enzymes. Because it influences flavour, a lot of research is devoted to it. A review by Lee and colleagues (2015) notes that good control brings out desired properties and prevents undesired fermentation that produces off-flavours. This applies to every fermentation, including wet processing.

On anaerobically fermented coffee, Febrianto and Zhu (2023), in an overview of new methods, conclude that the effect varies in strength depending on raw material and method. A single study by Fu and colleagues (2026) with Catimor from Baoshan in Yunnan (1,200 metres, harvest March 2023) fermented coffee for seven days in vacuum-sealed bags. There the anaerobic variants scored better than the conventional ones for fragrance, aroma, flavour, aftertaste, acidity, body and balance. Wet-processed coffee was cleaner and less sweet than dry-processed. One variety, one place, one year: that is not enough for a rule.

Origin or processing: which weighs more?

The Coffee Association calls both flavour-shaping, without a ranking. A dissertation at the University of Otago (Fernandez Alduenda, 2015) commits to one, namely origin. In one part of the work, Q-Graders rated coffees from 22 farms in Guerrero, Mexico, across four processing methods. In a second part, a panel trained at the University of Otago described 22 natural coffees of different origins and 9 washed comparison samples that came from the same farms as nine of the naturals. There, country of origin weighed more than processing. Natural differed clearly from washed above all when it showed a mocha character. A master’s thesis at the University of Pretoria (Viljoen, 2019) found, in 20 Arabica samples, that they grouped by geographical origin. Our assessment: both count, and we do not claim a fixed ranking.

For individual origins there are documented fragments. In Viljoen, Brazilian samples were described with caramel, fruit, herbs and nut, African ones with varied floral, fruity and spicy notes, some of them (Zimbabwe, Ethiopia Limu, Malawi) rather earthy, with peanut, cedar, herbs and citrus. The thesis does not mention chocolate for Brazil. The national coffee institute ICAFE describes individual regions for Costa Rica: Los Santos with Dota and Tarrazú lies at 1,200 to 1,900 metres, around 95 per cent of it is SHB, harvest runs from November to March, mostly under shade, and ICAFE describes the cup as having good body, high, fine acidity and slightly chocolatey. For Tres Ríos at 1,200 to 1,650 metres, the institute cites a very high, fine acidity and very good body. These are self-descriptions, not measurements. The rule of thumb that East Africa means fruit and South America means nut and chocolate is, on this evidence, a rough dealer tendency and no more.

What we found no source for is collected here once: a peer-reviewed study with flavour profiles for individual countries such as Kenya, Colombia, Guatemala, Honduras, Sumatra or Ethiopia; an assignment of origins to brewing methods or to suitability with milk; a specialist source for the gradations yellow, red and black honey; a fixed flavour profile for anaerobically fermented coffee; evidence that large beans such as AA roast more evenly or that AB is the most common Kenyan grade; and an altitude limit in metres for Nicaragua. If you read something like this on a bag, it is the seller’s claim, which you cannot verify.

Varieties: what the World Coffee Research catalogue says

World Coffee Research (WCR) maintains a variety catalogue with origin, growing characteristics and a quality potential for high altitudes. The catalogue gives a flavour description for Geisha (see FAQ), but not for Bourbon, Typica, SL28 and Pacamara. Notes such as blackcurrant for SL28 therefore do not come from there.

According to WCR, SL28 is widespread in Kenya, Malawi, Uganda and Zimbabwe and is susceptible to rust, coffee berry disease and nematodes. For the bag, this means: a variety with high potential does not promise a particular cup, it sets a framework that location and processing fill in.

Common misreadings of the label

Most misunderstandings arise because a word sounds like it specifies more than it does.

• The bag says highland, but gives no altitude. Cause: the term is not defined. What you do: treat the statement like a missing altitude and look for metres on the manufacturer’s site.
• AA is read as a quality grade. Cause: it is a screen grade. What you do: look at region and processing, and for a specialty bean at a score.
• SHB or SHG without a country. Cause: every country draws its own limits. What you do: find the country and compare it with the table above.
• Only a continent as origin. Cause: a blend of several countries. What you do: no conclusions about altitude or processing can be drawn from it, and the flavour description remains manufacturer text.
• No roast date. Cause: it is voluntary. What you do: ask the roaster or choose a bag with a roast date if age matters to you.
• Off-flavours despite good origin. Possible causes: Lee and colleagues name poorly controlled fermentation, which can occur with any method; Bertrand and colleagues found green and earthy off-notes at high temperatures and plenty of sun. What you do: try a different lot, because a country of origin does not protect against faults in processing.

Examples from our reviews

How differently detailed roasters are is shown by five beans from our comparison. The Incapto Single Origin Kolumbien gives the most: the Huila region, the municipalities of Pitalito and Acevedo, 1,400 to 1,800 metres, the Castillo Supremo variety, washed (listed as Lavado in the table), according to the manufacturer 84 SCA points and a lot from the secondary harvest. Harvest year, lot number and roast date nevertheless remain open.

The 360° Rundum Ehrlich Bio Honduras comes, according to the seller, from above 1,300 metres, grows under shade trees, is harvested by hand, washed and dried on drying beds. According to the CEPAL table, this altitude in Honduras would fall in the SHG range, but the seller makes no such statement itself. Variety, harvest year, lot number and the name of the cooperative are missing.

For the Mount Hagen Espresso Bio, the product page lists three cooperatives: HOAC in Papua New Guinea, Atahualpa in Peru and Sidama in Ethiopia, shares not stated. It speaks of highland Arabica, without metres. The beans dry for five to ten days in the sun to about 12 per cent residual moisture; whether washed or natural remains open. The Lavazza Tierra for Planet is 100 per cent Arabica from Africa and South America, on the page for the 500-gram bag also from Central America, floral and fruity and lightly roasted according to Lavazza. And with the Amazon Colombian Medium Roast, the origin ends at the country; in the catalogue, the region of origin is given as Belgium, presumably the place of roasting. For more on roast level and storage, see the guide Coffee beans basics.

Origin and brewing method

No source we found documents which origin suits which preparation (see the list above), not even for espresso with milk. What is documented is a difference that depends on the preparation and not on the bean: paper filters hold back oil-soluble substances that reach the cup through the metal mesh of the French press (figures in the FAQ above).

Our assessment: use the preparation you like anyway, and with a new bean change only one variable at a time. The procedures are in the guides Pour-over and filter coffee and French press guide.