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Agriculture

Long live the difference

Advances in the selection of coffees with unique flavors or aromas

eduardo cesarAgronomist Gerson Silva Giomo deferentially points out the tall, bushy and uniform coffee trees that form a green blot alongside one of the dirt roads on the Fazenda Santa Elisa, just outside the city of Campinas. They are the result of almost a century of genetic improvement, which has made productivity jump by 250%. Then Giomo smiles discreetly when he points out on the other side of the small road what interests him most: row upon row of small, disheveled and decidedly inelegant coffee trees.

“Who said these ugly, small plants bearing little fruit cannot produce quality coffee?” he asks. “The bigger the difference between the plants the greater the chance of finding fruit with characteristics that are of interest to coffee producers and connoisseurs”. Heading up the special coffees’ program at the Agronomy Institute of Campinas (IAC), Giomo is collecting the coffee beans that are likely to result in sweeter, more full-bodied, light, chocolaty or fruity coffees, to be drunk slowly, not downed quickly while standing at a street-corner snack bar, or used in coffee blends and meat sauces.

In July Giomo accompanied the harvest of little-valued coffee beans, which were separately packed. He waited for the beans to dry slowly over a 30-day period in one of the IAC’s drying sheds and was close by when they were roasted and when the greenish beans took on color, aroma and acidity, before being ground and used for making one of the world’s most widely consumed beverages.

Then as a taster certified by the Specialty Coffee Association of America (SCAA) Giomo chose the coffees with the most original tastes and aromas that he intends presenting this month to a group of tasters, at least two of whom will be from the United States. “They’re the people who are going to tell us which varieties we should pay more attention to at the IAC”, he guarantees. The SCAA establishes 10 items for evaluation, such as taste, aroma, sweetness, acidity, body, after-taste and balance. Higher acidity is valued, but it depends on the type of acidity: “A citric or fruity acidity is good; acetic acidity, which is reminiscent of vinegar, is bad”.

When the researchers have chosen the best of the best they must go back to the countryside and expand the productivity of the plants on which the coffee beans that most impressed the tasters grew. Giomo believes that in seven years the producers may have in their hands at least ten new varieties that combine remarkable and special taste and aroma characteristics, that are also acceptably productive. “We want the results to reach the interested producers as quickly as possible”, adds Oliveiro Guerreiro Filho, director of the IAC’s Coffee Center.

Sugarcane, the example
It was the integrated work with producers that revived the IAC’s program for the genetic improvement of sugarcane. At the end of the 1980s, Marcos Landell, then a recently-hired researcher, found the program on its last legs: the most experienced specialists were retiring and there was no new research in sight. Right after, two research programs in sugarcane that were set up in the 1970s shrunk, encouraging the IAC to reorganize itself in this area. “As there were few of us, we tried to organize ourselves”, says Landell. He and two colleagues from other IAC units, Pery Figueiredo and Mário Campana, looked for technicians from sugar and alcohol producing mills and researchers from universities and other institutions. For a year they met once a month in the Ao Leste do Éden bar to raise problems and discuss possibilities for action. The conversations, he guaranteed, were very productive, but the wife of one of them complained of the late nights and did not believe they were technical meetings, so in April 1992 they started meeting at the IAC in Ribeirão Preto. They swapped beer for coffee and tea, but the group had already grown from half a dozen to round 40 participants – today there are 130. Together they planned and tested new harvesting techniques, identified new cane varieties that could be used and detected and fought the pests and diseases that were beginning to appear.

A consultation at an agricultural fair held in the IAC indicated that producers wanted cane that was more suitable for feeding cattle. “We saw that there were more than 1.5 million livestock farmers who were using sugarcane for their cattle; that was more than were using it for ethanol”, says Landell. His team, along with colleagues from the Animal Science Institute and from Embrapa, identified a less fibrous and sweeter forage cane from the IAC’s own collection that was capable of incasing milk production in cows  that was launched in 2002. “We rose from the ashes, without resources, but with the willingness of people from the mills and the administration of the institute, who left the way open for us to act creatively”, commemorates Landell, who since 1995 has been heading up the research center and coordinates the cane improvement program. The hiring of nine researchers in 2005 expanded the joint work being done with other research centers in Brazil and other countries.

This type of approach, if it works again, might result in coffees with special tastes, making Brazil respected not only for the quantity of its production but also for its quality. Brazil is today the world’s biggest producer of coffee: the 2011 crop is likely to reach 43.5 million 60 kg. sacks. Just two species, the most productive so far encountered, account for this coffee mountain: Coffea arabica, which produces the beans used in coffee consumed as a drink occupies 76% of the coffee plantations, while Coffea canephora, also called robusta or conillon that is used in soluble coffees, occupies the other 24%.

Eduardo CesarAt the IAC: fruit in two stages of ripeningEduardo Cesar

Genetic improvement has led to an increase in productivity of 250% since 1727, when Sgt. Francisco de Melo Palheta planted the first coffee saplings in Pará, which he brought secretly from French Guyana. On the other hand, quality was not emphasized so much. “Genetic improvement eliminates diversity and values productivity”, says Maria Bernadete Silvarolla, a researcher at the IAC.

The new varieties are likely to be chosen from rarities that are growing on the IAC’s farm, some of which do not even look like coffee trees; they are elongated and have broad leaves, like a jackfruit tree. This collection of coffee trees, the biggest in the country, started to be grown in 1932 with varieties brought from Ethiopia, Kenya, Costa Rica, El Salvador and Guatemala. Over an area of 70 hectares there are 120,000 plants of 15 species or combinations of them. “Because of the laws that have made it difficult to exchange genetic material with researchers from different countries”, says Bernadete, “it would be impossible to form a collection so rich in genetic diversity today.”

One of the wild species that grow near the coffee research center is Coffea eugenioides. This is a bush with small leaves and very small red fruit, from which a smooth, clean coffee is produced that has low astringency and a slightly floral aroma. Recent studies have indicated that this species is one of those from which Coffea arábica was formed. Another important conclusion: the sweetness and pleasant aroma of this most commercially grown species come from the genes inherited from C. eugenioides.

“The rise of Coffea arabica was a very fortunate, spontaneous phenomenon that took place around 700,000 years ago, combining the genes of Coffea eugenioides with a more robust species, Coffea canephora”, says Carlos Colombo, a researcher at the IAC who is a member of a specialist team that has ramifications in several states and who analyzes coffee genes.

The problem is that the productivity of these wild species is normally low and it is not at all easy to make these varieties produce more by crossing them with others, without losing the special flavors. A coffee tree takes two years to bear fruit for the first time and it is only considered to be a new variety candidate if it produces berries with the desired characteristics and in reasonable quantities for at least four consecutive years.

A naturally decaffeinated coffee variety shows how the work in this field can take a long time. Bernadete examined the amount of caffeine in the beans of 3000 plants until she found 3 from Ethiopia that had 0.07% caffeine, while a widely used commercial variety of Coffea arabica called Mundo Novo [New World], in comparison, has 1.2%. In a 2004 article in Nature, she and other researchers from the IAC and the State University of Campinas (Unicamp) presented the probable reason for the low levels of caffeine: a deficiency in the amount or the functioning of the caffeine synthase enzyme, which transforms theobromine into caffeine. These three varieties, called AC, in a tribute to Alcides Carvalho, the researcher who led the coffee genetic improvement program at the IAC for 60 years, had much more theobromine than Mundo Novo.

Since 2004, Bernadete’s team has been crossing AC plants with others that are more productive. Four years later none of the 600 plants of this first generation had produced coffee without caffeine because , as is known today, this characteristic is due to the joint action of at least two genes that are both recessive: the beans will only have a low level of caffeine when a copy of a gene coming from one father and another copy coming from another father are recessive.

After another directed crossing and a further three years the researchers chemically examine the beans of the first crop of 400 second generation plants, hoping to find some that are capable of producing beans without caffeine and that are productive enough to justify growing them on a commercial scale. If they do find them perhaps they can produce other plants with this same characteristic more rapidly by cloning. Bernardete believes that naturally decaffeinated coffee could please refined palates and the palates of those who cannot take caffeine at the risk of suffering from insomnia or fainting.

Eduardo cesarSlight coffees, but with a distinctive flavorEduardo cesar

Isolated in the forest
There might be other rarities beyond the fences of the IAC. Coffee plantations today are rare in the Stat e of Sao Paulo (they have been replaced with sugar plantations and other crops that demand less fertile lands), but isolated coffee trees still flower in the middle of the remains of Atlantic rainforest. “Nature has carried out a genetic super-selection free of charge for us in the remaining forest stretches”, observes Sergius Gandolfi, a professor at the University of São Paulo (USP). “In forest fragments there are thousands of coffee trees that are probably unique in taste, resistant to disease or capacity to grow in the shade, which have resisted competition from other plants and pest attacks and lived in an isolated way, without exchanging genes with other coffees trees from other fragments, for a century, perhaps 20 generations.”

The quality of the beans and the drink does not only depend on genetics, but also on the environment and the processing. This is why the team from the IAC intends getting the collaboration of producers who can grant it land, all over the country if possible, to assess whether selected plants keep their desired qualities in other environments. If they manage, then perhaps they can shorten the development time of new varieties; those that work out will already be on the producers’ land.

Another possibility is to modify the environment so the plants can express their qualities. It is already known that the coffee tree grows better in higher areas, like those in Minas Gerais and the Alta Mogiana region in São Paulo, and that partial tree-cover can compensate for low altitude and help improve quality. The coffees of Ethiopia and Kenya are among the best in the world because they grow in the middle of forests, their original environment, with less stress, and the fruit can ripen more slowly and produce the substances that accentuate taste and aroma.

Gandolfi recalls that a study done in Costa Rica indicated that the production of beans could be 20% greater when there is a forest close to the coffee plantations. Proximity also benefited the quality of the beans, because it facilitates pollination, which is more effective when done by native bees. “In times when the Forest Code is changing”, he says, this evidence “contradicts the opinion that small land-owners do not need forests.”

The production of specialty coffees may also demand changes in harvesting and the processing. Ripe berries may have to be picked at various times,  at various moments; today the harvester strips from the branches both green and ripe fruit, the color of which varies from pale yellow to intense red depending on the species, and those that are ready are dried, then separated later. The berries may dry more rapidly on the cement drying floors on which they are spread, as was done more than one hundred years ago, or more slowly in suspended dryers, or a little in the sun and then in mechanical dryers. There is still a lot of work (and coffee) ahead.

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