Background information

Background information / Coffee and the environment

Pesticides used on coffee farms, part 2: Common coffee pests

Coffee is equipped with an excellent defense against herbivory: caffeine. Caffeine is one of many alkaloids that evolved in various plants to prevent them from being eaten by insects.  Evolution doesn’t stand still, however, and some insects have fought back. Coffee is attacked by several pests and diseases. Here are the most important, the ones that are most frequently combated with pesticides.

Coffee cherry/berry borer or “Broca” (Hypothenemus hampei). Native to Central Africa, but now found in many coffee-producing nations. The female of this tiny beetle (shown here on a green coffee bean) bores into the coffee cherry and lays about 15 eggs; the larvae feed on the developing bean. Usually, the cherry drops from the tree. The best defense is making sure there are no unpicked beans left on the trees or laying on the ground. Because they spend much of their life inside the cherry, controlling borers with insecticides can be difficult or downright ineffective.

Coffee leaf miner or “bicho mineiro” (Leucoptera coffeella). The leaf damage from the larvae of this small moth means less leaf surface is available for photosynthesis, resulting in stunted plants and reduction in yield. Native to Africa, but now found in many coffee-producing nations. This insect has developed resistance to insecticides in some areas.

Other insect pests include root nematodes (Meloidogyne spp.), green scale (Coccus viridis), and twig borers (Xylosandrus compactus).

Although not an insect, the next pathogen also prompts chemical onslaughts:

Coffee leaf rust (Hemileia vastatrix). A fungus that causes yellow spots on leaves, reduced photosynthetic ability, and eventually leaf drop. This causes a lack of nutrients going to growing shoots, and so can impact future growth of the plant. Spores require rain to germinate (high humidity is not adequate). Disease spreads more quickly in dense plantings and is less severe in shaded plantings, as the spores require a certain light intensity to germinate. Temperatures at farms at higher elevations are often too cool for the fungus.  Native to Africa, but now found in many coffee-producing nations. Some coffee cultivars have resistance, notably the catimor variety, and also catuai and mundo novo.

Next in this series: Common pesticides used on coffee farms.

Coffee berry borer on bean photo by P. Greb.

Background information

Coffee basics

Coffee & Conservation is all about helping consumers make the right choice when it comes to picking great coffee that is good for the environment.  Coffee reviews are by regular folks using, we hope, understandable language and ordinary techniques.  Still, it seems like it would be helpful to have a post that provides links to definitions of some of our terms, and how-to’s on making coffee.  This is that post!

Roast levels
Coffee retailers use a lot of terms to describe the roast color/level of their coffee.  Many Americans are used to a fairly dark roast (the place isn’t called “Charbucks” for nothin’). Dark roasts can overwhelm the delicate flavors of some beans, or caramelize sugars and lend a hearty smokiness.

Here at C&C, we try to provide the roast level indicated by the retailer, and then describe the color and whether or not oils are present on the surface of the beans.  Here are some guides to roast levels:


Grinding
Grinding is probably the most neglected step in coffee preparation.  Ground coffee gets stale in a hurry, and to really enjoy coffee, you have to have fresh beans that you grind before you make the coffee.  It is the simplest single thing to do to vastly improve your enjoyment of coffee.

Coffee grounds must be uniform at a fineness appropriate to your brewing method in order to have proper contact between coffee and water so that essential oils and flavors are released.  Blade (“whirly”) grinders grind unevenly.  Burr grinders are better.

At C&C we always grind our coffee immediately before preparation (2 tablespoons of ground coffee per 6 ounce cup), with either a decent blade or burr grinder.

Brewing methods
There are plenty of ways to make coffee.  For our reviews, we nearly always start off with a press pot (French press) to bring out all the flavors of a coffee.  We also try the coffee brewed, in a typical, middle-of-the-road drip coffee maker (like most people have at home) using unbleached paper or a gold filter. Occasionally, we also use an Aeropress or Eva Cafe Solo. Here is the low-down on these methods:

  • French press. Water just off a boil is poured over freshly ground coffee, steeped for about 4 minutes, after which a mesh plunger is pressed down, separating the grounds from the coffee.
  • Automatic drip.  Ground coffee is placed in a filter basket, and water drips through it.  Good coffee makers heat water to the proper temperature, distribute the water evenly over the grounds, and deliver the water at a speed that insures proper exposure time.  Because the water is in contact for such a brief time and the filter removes particulates (and even oils, in the case of a paper filter), coffee from a drip pot is clean and mild.  Temperature is a key component in this method — most cheap pots don’t heat the water hot enough (190-200 degree F).
  • Aeropress by Aerobie. A small device that forces the water through the coffee and a filter using air pressure, producing very smooth, full-bodied coffee in about a minute.

George Howell Coffee provides links to instructions for many brew methods; there are videos and you can download PDFs guides for each method.

Coffee flavors
One reason we began doing reviews at C&C was that we just didn’t “get” reviews at some other sites.  Personally, I could not fathom tasting brandied tomatoes or Meyer lemon in my coffee. Other sites were too general, or liked every coffee they tasted.  We try to strike a balance here at C&C, as best we can as regular folks, considering taste is pretty subjective.

Still, there are some commonalities and standards in coffee flavors.  Here are some great overviews and tutorials.

Those are some of the basics. There are also posts here on botanical varieties of coffee, as well as a link to variations in coffee taste by growing region.  If there’s anything else you’d like to see added to this post, just leave a comment.

 

Background information

Poverty and conservation, how coffee fits

The current issue (summer 2006) of the Nature Conservancy magazine has several articles on the poverty and conservation equation.  When I posted on “What is Fair Trade?” I wrote,

Worldwide, habitat destruction is the leading cause of bird population declines and loss of biodiversity. The link between poverty and environmental degradation is inescapable. Making sure that coffee farmers receive a living wage is one way to help preserve habitat — both by  encouraging sustainable coffee farming methods that produce the highest quality coffee, and by empowering farmers economically and reducing their need to exploit the environment for survival.

These points are expanded upon in the Nature Conservancy pieces. They give an example of coffee farming in the Dominican Republic:

Today, the farmers in this idyllic mountain community [Los Dajaos] in the Dominican Republic’s central highlands no longer denude the hillsides to plant beans and graze cattle. Instead, they tend organic shade coffee beneath a canopy of flowering guama trees. … After once clearing thousands of acres of habitat critical to preserving biodiversity and the island watershed, they have come to view the forest as a friend.

These articles surely help elucidate why sustainable agriculture is important to biodiversity, and it’s not hard to understand how sustainable coffee — as one of the world’s top commodities — can fit into this equation.

Background information

Botanical varieties of coffee

There are over 100 species of coffee (Coffea) in the world, and all are native to tropical Africa and some Indian Ocean islands (Madagascar, Macerenes). Most have very limited distribution, and over 70% are threatened with extinction.

Usually only two species, C. arabica and C. canephora, are commonly grown commercially.  They are described below, along with a few other interesting species, and the most common commercial varieties of these species.  Because certain types grow best in the shade and others in the sun, knowledge of these names can be a convenient clue as to how your coffee may have been grown.

Don’t confuse these botanical varieties with coffees named for their growing regions, such as Ethiopian Harrar, Guatelmalan Antigua, or Hawaiian Kona.

  • Coffea arabica. This is the highest quality coffee, used by specialty roasters. It grows best at higher altitudes — 3000 to 6500 feet — and because it grows slowly the flavors are more concentrated. This species tend to be susceptible to various diseases, and has a lower caffeine content than C. canephora (below). Arabica is a deep-rooted shrub. Unlike other coffee species, arabica has two sets of chromosomes. Arabica has two common varieties, typica and bourbon. These traditional, older varieties are the types most often grown in the shade. Because arabica is self-pollinating, these varieties are stable, but sometimes do mutate into strains that are then cultivated. Just a few of the most common are described.
    • Coffea arabica var. typica.
      • Maragogype — large-beaned (“elephant bean”) Brazilian mutation. Porous beans are not especially flavorful, and low-yielding. (Roasting a larger bean correctly takes some finesse, so buy from a specialty roaster.)
    • C. a. var. bourbon. Old variety originating on the Indian Ocean island of Bourbon (Reunion) with broad leaves, and small fruits. In Kenya, bourbons are sometimes called “French mission ” or “Scottish mission.”
      • Catuai — cross between Mundo Novo and Caturra. There are red (rojo) and yellow catuais, named for the color of the cherries. High yield and hardy. Often grown as sun coffee.
      • Caturra — compact, multiple-branching form of bourbon, common in Brazil and Colombia. Disease resistant and fast-maturing, the higher yield of Caturra apparently comes at a cost to good taste. Considered lighter-bodied and more acidic than traditional bourbons. Often grown as sun coffee, it requires a lot of management and fertilizer.
      • Mundo Novo — cross between typica and bourbon, high yield, popular in Brazil.
      • Paca — a high yielding cross between bourbon and Caturra.
      • Pacamara — cross between Maragogype and the Paca variety of Caturra.  Not considered very flavorful, as neither parent is especially revered for taste.

If you’d like to see a “family tree” of some of the arabica coffee varietals, check out this post by Jim Hoffman and a table of coffee genotypes from a paper published in the Brazilian Archives of Biology and Technology. More less-commonly referred to arabica varieties are described in the coffee glossary.

  • Coffea canephora.  This species is more commonly referred to as “robusta,” although this actually refers to the upright variety of canephora; there is a spreading variety known as nganda.  Robusta is a lower-growing and shallow-rooted, harsher and more bitter variety that is used in cheaper coffees, or as fillers.  Robusta tends to be more hardy and disease-resistant, will grow better in the sun than arabica, and tends to have higher yields. It has a higher caffeine content than arabica. I’ve written an entire post about robusta here.  Although there is such a thing as a decent quality robusta, Kenneth Davids at Coffee Review sums up the problem with most robustas in today’s market:

    Apparently with the support of the World Bank, robustas recently have been planted in very large quantities in Vietnam. These are mass-produced coffees at their most dramatic: stripped from the trees, leaves, unripe, ripe and overripe fruit and all, and dried in deep piles. All of which means the essentially bland, grainy robusta character is topped off with an assortment of off-tastes, mainly musty/mildewed and fermented. These coffees sell for considerably less than all other coffees, including better quality robustas. I am told that production costs for Vietnamese robustas are about 20 cents per pound or less, compared to, for example, production costs of 80 to 90 cents per pound for the excellent “100% Colombia” coffees competing in the supermarket. And now the current episode: Commercial dealers and roasters have learned to steam the often foul-tasting Vietnamese robustas, removing the waxy covering of the bean and muting (but not entirely eliminating) the offensive flavor notes.

There are some hybrids between arabica and canephora. They include:

  • Hibrido de Timor — a natural hybrid, with two sets of chromosomes like arabica.
  • Icatu — backcrosses of Hibrido de Timor with Mundo Novo or Caturra.
  • Catimor — cross between Caturra and Hibrido de Timor. High yields, often grown as sun coffee, with a reputation for inferior quality.

One other species is grown commercially:

  • Coffea liberica. Similar to robusta, grown at low altitudes in Malaysia and West Africa, it accounts for less than 1% of commercial trade. In the cup, it is thick and pungent, but has its fans in some countries.  It is known as Barako in the Phillipines.  Two subspecies are commonly recognized, C. liberica var. liberica, just called “Liberica” or “Liberian” coffee, and C. liberica var. dewevrei, known as “Excelsa.”

There are a number of varieties in Madagascar and the Mascarene Islands that have little or no caffeine, including C. kianjavatensis, C. lancifolia, C. mauritiana, C. macrocarpa and C. myrtifolia. These species are in the taxonomic section Mascarocoffea; this is not a genus as is frequently reported on the Internet. Arabica and robusta coffees are in the section Eucoffea, and attempts to breed Eucoffea varieties with caffeine-free traits from Mascarocoffea types has not been successful.

Finally, peaberry (“caracol”) coffee is not a botanical variety, but a bean mutation where the cherry produced one small, rounded, fused bean rather than two flat-faced beans. May occur in any botanical variety, usually accounting for about 10% of the crop.  Some think peaberries have a superior taste, but choose a roaster widely, since peaberries roast quickly and are easily charred.