A new era in the history of Brazilian coffee is unfolding. Inverting the trend consolidated in the 1960s by the now extinct Brazilian Coffee Institute (IBC), which focused on continual output increases to cover sales to other countries, the priority is now quality. Dictated by market opportunities and supported by studies conducted at educational and research institutes, this shift primarily applies to the Coffea arabica (or arabica) species, which accounts for 80% of plantations in Brazil. Generally speaking, this type carries less caffeine, a stronger aroma, and more sweetness and acidity than the other species grown in the country: C. canephora (or canephora), for which efforts are ongoing to increase both quality and output.
For coffee growers, the change in strategy means constant attention to cropping and processing techniques, using equipment capable of more accurately defining the chemical and sensory features of the grains, leading to higher prices than for more common varieties. For a growing group of consumers, this turnaround enhances the pleasure of choosing between the grains which, grown and roasted in different ways, account for the most highly consumed nonalcoholic beverage in Brazil, second only to water.
– Coffee consumption caution required
– Climate change expected to affect Brazilian coffee
“Coffee is going the same way as wine, where value is conferred upon the type, origin, method of preparation, and other characteristics that reinforce its identity,” says geneticist Douglas Silva Domingues, of the Luiz de Queiroz College of Agriculture of the University of São Paulo (ESALQ-USP), who was part of the international team that genetically sequenced C. arabica; the results were published in the journal Nature Genetics in April. According to this study, the plants providing most of the coffee consumed around the globe were the result of a natural fusion — or hybridization — of two other species, C. eugenioides and C. canephora, between 1 million and 600,000 years ago in the region now known as Ethiopia. Previous estimates indicated that this merger occurred only 10,000 years ago.
Brazil’s fourth key agricultural product after soy, corn, and sugarcane, and accounting for 2% of the country’s Gross Domestic Product (GDP), coffee is responsible for 8.4 million direct and indirect jobs, but not always under appropriate working conditions. According to the Labor and Employment Ministry (MTE), between 1996 and 2023 some 3,700 workers were found to be operating under slave-like conditions in coffee plantations across the country. In the first half of 2023, a total of 302 people were rescued from coffee farms.
Brazil is the world’s foremost producer, with 66 million sacks of 60 kilograms (kg) in 2023, equivalent to 37% of global output according to the Ministry of Agriculture, Livestock, and Supply (MAPA), and is second only as a coffee consumer to the United States (see infographic). According to a nationwide survey undertaken by the Campinas Institute of Agriculture (IAC) and published in November 2023, almost half (49%) of the 4,200 interviewees (1,890 men and 2,310 women) were drinking between three and five cups a day, with 29% consuming more than six cups a day; at home, when out, while waiting for the bus or the subway, in the café with friends, or at work.
“The COVID-19 pandemic created a coffee microworld, as many people could not go out, and isolated at home, started to try new types and preparation methods, observes Sérgio Parreiras Pereira, agricultural engineer at IAC and mediator of the Coffee Social Network (RSC), made up of almost 6,000 producers, roasters, exporters, and government agency and university staff.
Geographical indications
In recent years, the National Institute of Industrial Property (INPI) has conferred 14 geographical indications (IG) upon arabica coffee, and two on canephora. This title recognizes the characteristics of a range of products and services based on the place of origin, and provides them with identity, prestige, and value (see Pesquisa FAPESP issue nº 309). In November 2023, a coffee that grows at 1,030 meters (m) above sea level in the Cerrado (wooded savanna) region of Minas Gerais State was chosen as best in the world during an international competition. Its flavor, aroma, and sustainable cultivation techniques saw it selected by producers from nine countries: Brazil, Costa Rica, El Salvador, Ethiopia, Guatemala, Honduras, India, Nicaragua, and Rwanda. According to the Brazilian Coffee Industry Association (ABIC), only 4% of production in Brazil employs sustainable techniques, increasingly demanded by buyers from other countries.
“As a result of improved post-harvest care, we now produce coffees as good as those from Colombia, which are considered the best in the world,” says agricultural engineer Celso Vegro, of the Institute of Agricultural Economics, linked to the São Paulo State Department for Agriculture and Supply. He compares three types of mature grain, also known as cherries, the product of post-harvest treatment: de-husked coffee, which loses its outer skin on passing through a machine prior to drying; washed, which spends up to two days fermenting in tanks with water; and coffee sun-dried in open-air concrete yards, assisted by mechanical dryers in high-humidity environments. Each process results in beverages with different flavors and acidity levels. “The semi-washed, de-husked cherry, from which we produce 5 million sacks per harvest, perfectly substitutes the Colombian washed variety,” says Vegro. “From the washed variety, de-husked and dried in the sun, we produce one million sacks.”
Léo Ramos Chaves / Revista Pesquisa FAPESPRed catuai from the Monte Alto farm in São Carlos, interior of São Paulo State and drying tests at IACLéo Ramos Chaves / Revista Pesquisa FAPESP
Agricultural engineer Flávio Meira Borém, of the Federal University of Lavras (UFLA), in Minas Gerais, agrees: “We produce coffees with the same level of quality as any other in the world.” In his opinion the disadvantage is the marketing, which has established the high-quality image of Colombian coffee. “In a blind test on samples from Brazil, Colombia, and Ethiopia, ours stands out, however looking at the packaging, the consumer sees Colombian coffee as better. But it is not. Of the Colombian output — 11.5 million sacks from the 2022/2023 harvest — at least half are fine coffees, handpicked and containing only mature rather than green grains, which adversely affect the flavor, whereas in Brazil, 10% at most are special coffees, also known as fine; most of Brazil’s production is of lower-quality grains.
Perhaps this scenario will change little by little. “As output increases, the trend is to intensify efforts to obtain higher percentages of better-quality coffees in detriment to the more basic ones,” ponders Vegro, who states that the space for fine coffees also expands as more people learn to appreciate higher-quality versions.
Reworked concepts
In the midst of the scientific research that has enabled such advances, certain old-fashioned ideas are coming undone. For example, the two varieties of C. canephora, conilon and robusta, considered less refined than C. arabica, can also produce coffees with a good sensory evaluation — up to 89 points from a total 100. In experiments conducted at the Federal University of Espírito Santo (UFES), canephora grains released aromas of roses, cinnamon, and blackberries after undergoing a long period of fermentation (from 5 days for conilon, and 15 for robusta) and, in the specific case of conilon, also assisted using the yeast Saccharomyces cerevisiae. Canephora is widely used to produce instant coffees and to reduce the acidity of the beverage when mixed with arabica.
“Fermentation is an alternative for producers to diversify the sensory profile of their coffees,” says Borém. The best sensory qualities obtained from arabica were after two to three days’ fermentation using the bacteria Lactobacillus plantarum and S. cerevisiae, according to a UFLA study to be published in this year’s June edition of Food Chemistry.
“Several growers in the north of Espírito Santo State are already producing fermented coffees, with or without yeast,” comments food engineer Bárbara Zani Agnoletti, lead author of a November 2022 study published in Microchemical Journal, which details the possibilities for ennobling canephora. Amazon robusta coffee, grown in the northern Brazilian states of Rondônia and Amazonas, has won consumers over with its aroma and flavor, achieved through natural or induced fermentation (see Pesquisa FAPESP issue nº 282).
Léo Ramos Chaves / Revista Pesquisa FAPESPQuality results from husbandry through all production stagesLéo Ramos Chaves / Revista Pesquisa FAPESP
Borém and his group have debunked another principle: it is possible to produce fine coffees, scoring at least 80 points on the 100 scale, with green grains, usually considered as restricted due to their adverse effects on flavor. Funded by Chinese multinational Syngenta, the UFLA team developed a technique to formulate a coffee from 50% green grains and 50% mature. “The green fruit can be harvested earlier, contains more antioxidants, and its unpleasant taste can be eliminated through a technological process,” he says, not elaborating any further because the technology is currently in the licensing phase.
Another notion was also disproven: special arabica coffees can bear fruit not only in environments over 1,200 m above sea level, but also on lower ground, provided the soil contains a specific portion of an iron-oxide derivative, detected by a group from São Paulo State University (UNESP) (see Pesquisa FAPESP issue nº 336). This dispels the rule that only high altitudes can provide grains with a fruity aroma combined with spices, and that only lower regions can produce grains giving off citrus, chocolate, or nutty aromas after roasting and extensive grinding.
Field innovations
Research centers continually present proposals for improvements in planting, harvesting, or processing of grains. In November 2023, the IAC concluded a 30-year research project coordinated by agricultural engineer Oliveiro Guerreiro Filho, and launched a rootstock (root and stem base), resulting from the combination of five varieties of C. canephora, and resistant to roundworms, which cause losses estimated at 20% of Brazilian output. A stem may be inserted into the rootstock to form the plant top, producing coffee of the desired variety.
Almost 13 years ago, during an early afternoon in August 2011, agricultural engineer Gerson Silva Giomo, coordinator of the IAC special coffees program, drew attention to a series of small, disheveled coffee plants. “Who said that these small, ugly, almost fruitless plants cannot produce quality coffee?” he asks. “The more different the plants, the better the chance of finding fruit with sensory characteristics of interest to producers and appreciators” (see Pesquisa FAPESP issue nº 187).
In February this year, the researcher reported that he and his team selected some of those plants, producing hundreds of seedlings through tissue culture (as they were hybrids and did not multiply by way of seeds), and planted them in areas of different climate, altitude, and soil in the states of São Paulo and Minas Gerais. Three harvests later, they singled out three groups of plants capable of producing different special coffees, scoring a minimum of 87 points on the Specialty Coffee Association (SCA) classification scale. The plants are the result of merging varieties out of Ethiopia, such as gesha, which gives rise to quality coffees, from Panama, and other arabicas, such as catuai and obata, which ensure productivity.
Mateus Bonomi / Anadolu Agency via Getty ImagesQuality checking of roasted grains ready for grinding at a café in Brasília (left); at the same establishment, an employee inspects sacks of coffeeMateus Bonomi / Anadolu Agency via Getty Images
“The new varieties are now ready for large-scale production by specialized companies for subsequent distribution to growers,” says Giomo. “As we have validated the seedling production method from leaf cells — somatic embryogenesis — we can now enjoy time gains to cross other varieties.”
At EMBRAPA Instrumentação (Instrumentation Center of The Brazilian Agricultural Research Corporation), in the inland São Paulo State city of São Carlos, computer scientist Ednaldo José Ferreira is in the final phase of testing a system that may facilitate the work of coffee tasters tasked with classifying the beverage based on aroma (smells associated to the flavor), acidity, fragrance (aromas that cannot be tested, such as wood or metal), and bitterness. The CoffeeClass system uses a digital microscope to amplify images of roasted, ground grains by up to 200 times, followed by measurement of the fluorescent or reflected light spectrum; then, using artificial intelligence, the sample is classified into one of the four quality groups adopted by ABIC, in descending order: gourmet (including special), superior, traditional/extra-strong, and not recommended (see infographic).
“Through sensory analysis, a gourmet coffee, with atypical bitterness and low astringency [sensation of the tongue contracting and drying, such as when we eat bananas or cashew fruit], may be interpreted as a superior, and vice versa, if the quality level is close to the limit separating the two classes,” explains Ferreira, according to whom the new method provides a clearer classification by recognizing defective grains that impair the quality of the coffee.
In January, after blind-testing 20 samples provided by ABIC with a 75% accuracy margin, Ferreira began working with a bigger sample base of 230 coffees from different regions of Brazil. His aim is to achieve CoffeeClass validation, a stage prior to licensing and scaling commercial production of portable versions of the equipment for use by producers and coffee shops.
At UFES, Agnoletti used a spectroscope in the infrared region — one of the methods of measuring the intensity of light absorbed by a substance, to examine the terroir, or the sensory identity of a beverage, defined by its chemical composition resulting from interaction between genetics, climate, soil, and post-harvest care. He analyzed samples from conilon, robusta, and hybrid C. canephora samples collected in 2021 across different Brazilian states: 60 from Espírito Santo, 153 from Rondônia, 24 from Bahia, 15 from Minas Gerais, and 10 from São Paulo, all prepared in the same manner.
In this study, detailed in Food Research International in January, the genetics of each variety had more impact on formulation of the terroir than the crop location. Coffees from São Paulo, Minas Gerais, and Bahia presented no terroir, approximating to those of Espírito Santo and Rondônia. The reason? According to Agnoletti, the varieties, moved from one region to the other, probably did not have time to differentiate. “This analysis technique could help to authenticate, differentiate, or group terroirs, which form the basis for geographical indications,” she says.
At UFLA, agricultural engineer Luiz Roberto Guimarães Guilherme has been using a portable fluorescence spectrophotometer — a type of X-ray sensor — to evaluate, in a few seconds, the key components of soils, production inputs and the nutritional state of the leaves of coffee plants growing in experimental lots in southern Minas Gerais, thereby facilitating analyses, until now conducted in the laboratory. “Producers get excited because they can see first-hand where they need to adjust the fertilization, and want to buy identical equipment,” he reports.
Léo Ramos Chaves / Revista Pesquisa FAPESPDigital CoffeeClass microscope, a system capable of recognizing defects in roasted, ground grains, developed by EMBRAPA InstrumentaçãoLéo Ramos Chaves / Revista Pesquisa FAPESP
As such apparatus is imported and costly, Guilherme’s team is looking at the possibility of using and even producing other sensors to conduct similar analyses. There is a cell phone application under development that will provide information, albeit simplified, on the nutritional state of the plant using photos of the leaves. In the laboratory setting, Guilherme is evaluating an electronic nose, with sensors for gases, to assess the aromas and quality of toasted and ground grains. Articles published in 2023 in the journals Environmental Research and Chemosphere detail advances in the use of the sensors.
“Coffee has a higher proportion of aroma-associated genes than the average in other plants,” comments Domingues, of USP. He participated in a study coordinated by Swiss giant Nestlé comparing C. arabica genomes with the two species from which it originated: C. eugenioides and C. canephora. “We saw an expansion in the number of genes related to a group of enzymes — terpene synthases — which produce terpenes, associated to the fruit’s taste and aroma, and we identified which of them are active in the green and in the mature fruit, influencing quality,” he goes on.
This study was published as a preprint in November 2023 in the bioRxiv repository, marking scientific competition between the biggest coffee producers: in January, Nature Communications published the genome of a C. arabica variety known as Bourbon, originating from Ethiopia and grown in a number of countries — in the Minas Gerais Cerrado in Brazil — that stands out for its sweetness, fruity aroma and chocolatey flavor. Funded by Italian corporation Illy, the study demonstrated that subtle variations in taste and aroma in the same variety have resulted from the exchange, elimination, or rearrangement of genes.
For Domingues, there is still much to be done, because basic coffee genetics research in Brazil slowed down after the work of genetic enhancement pioneers, including agricultural engineers Carlos Arnaldo Krug (1906-1973) and Alcides Carvalho (1913-1993), both of the IAC, and with an emphasis on applied research. “There is currently much more research material on the basic genetics of sugarcane than coffee,” he remarks. Step by step though, it is becoming more evident which genes and cultivation in preparation conditions make for a good coffee.
Projects
1. From seed to cup: The internet of things in the high-quality coffee production chain (nº 21/06968-3); Grant Mechanism Thematic Project; Agreement MCTI; Principal Investigator Luiz Roberto Guimarães Guilherme (UFLA); Investment R$2,844,768.54.
2. Bridging gaps between biological resources in the genus Coffea and the new challenges of making improvements in the face of global changes: Coffea-Bridges (nº 23/03353-3); Grant Mechanism Regular Research Grant; Principal Investigator Douglas Silva Domingues (USP); Investment R$325,510.00.
3. A systemic approach to understanding the impact of climate change on Coffea spp. (nº 18/08042-8); Grant Mechanism Regular Research Grant; Principal Investigator Douglas Silva Domingues (USP); Investment R$367,538.11.
4. Chemical descriptors and emerging green technologies in combination with chemometrics for characterizing and evaluating fine coffees from Brazil (nº 19/21062-0); Grant Mechanism Doctoral (PhD) Fellowship; Supervisor Juliana Azevedo Lima Pallone (UNICAMP); Beneficiary Michel Rocha Baqueta; Investment R$283,376.69.
Scientific articles
AGNOLETTI, B. Z. et al. Effect of fermentation on the quality of conilon coffee (Coffea canephora): Chemical and sensory aspects. Microchemical Journal. vol. 182, 107966. nov. 2022.
AGNOLETTI, B. Z. et al. The terroir of Brazilian Coffea canephora: Characterization of the chemical composition. Food Research International. vol. 176, 113814. jan. 2024.
ANDRADE, R. et al. Proximal sensing provides clean, fast, and accurate quality control of organic and mineral fertilizers. Environmental Research. vol. 236, 116753. nov. 1, 2023.
BENEDET, L. et al. Clean quality control of agricultural and non-agricultural lime by rapid and accurate assessment of calcium and magnesium contents via proximal sensors. Environmental Research. Vol. 221, 115300. Mar. 15, 2023.
DA COSTA, M. V. et al. Towards direct and eco-friendly analysis of plants using portable X-ray fluorescence spectrometry: A methodological approach. Chemosphere. vol. 339, 139613. oct. 2023.
SALOJÄRVI, J. et al. The genome and population genomics of allopolyploid Coffea arabica reveal the diversification history of modern coffee cultivars. Nature Genetics. vol. 56, pp. 721–31. apr. 15, 2024.
RABELO, H. S. et al. Fermentation of coffee fruit with sequential inoculation of Lactiplantibacillus plantarum and Saccharomyces cerevisiae: Effects on volatile composition and sensory characteristics. Food Chemistry. vol. 444, 138608. june 30, 2024.
SALVIO, L. G. A. et al. Fermented natural coffee followed by pulping: Analysis of the initial sensory quality and after six months of storage. Coffee Science. vol. 18, e182120. sept. 1, 2023.
SALOJÄRVI, J. et al. The genome and population genomics of allopolyploid Coffea arabica reveal the diversification history of modern coffee cultivars. Preprint. bioRxiv. nov. 11, 2023.
SCALABRIN, S. et al. A chromosome-scale assembly reveals chromosomal aberrations and exchanges generating genetic diversity in Coffea arabica germplasm. Nature Communications. vol. 15, no. 463. jan. 23, 2024.
