2 Coffee beans
  2.1 About coffee beans
    2.1.1 What are coffee beans?
    2.1.2 Arabica and robusta
    2.1.3 How important is the beans' country of origin?
    2.1.4 What's the difference between dry processing and wet processing?
    2.1.5 Jamaican Blue Mountain
    2.1.6 Kona
    2.1.8 Why are some coffees aged?
    2.1.9 What's a monsooned coffee?
    2.1.10 What is a "peaberry"?
    2.1.11 What are "espresso beans"?
  2.2 What is the difference between the various decaffeination processes?
    2.2.1 Solvent (European) process
    2.2.2 Water Process
    2.2.3 Carbon Dioxide Process, Sparkling Water Processes
  2.3 Flavor terms
  2.4 Roast names
  2.5 Coffee bean size classifications
  2.6 What is a cultivar?

2.1 About coffee beans
Fresh beans are critical, and perhaps the commonly overlooked factor. Try to find a local roaster, or a coffee retailer where they can verify the roasting date, which should be no more than a week before sale. Look to see that the retailer is relatively busy and that their stock turns over frequently. Be suspicious if they store the coffee in containers that are exposed to the air, such beans will stale more rapidly than those stored in airtight containers. Some "gourmet" shops store their roasted beans in large, open containers holding twenty pounds each or more. Unless they're selling a truly amazing amount of coffee, much is it is likely stale.

If a supermarket without an in-store roaster is your only option, look for sealed plastic, Mylar, or foil bags with the roasting date printed on them. You want a roasting date, not an expiration date—the latter is misleading, since you don't know whether the retailer is being unrealistically optimistic about how long they consider the beans to be fresh. The pre-ground, canned coffees sold in supermarkets are de facto stale (though many people believe that Illy canned coffee, which is packed under pressure, not vacuum, is an exception to this rule).

Foil-wrapped vacuum-packed containers (where the package tightly conforms to the beans) should be avoided; since freshly roasted beans emit carbon dioxide, the tight packaging (i.e., the fact that the bag has not inflated), indicates that this outgassing has stopped and the beans are stale (the Illy canned coffees are again an exception, since the cans resist distension). The carbon dioxide emission lasts for up to two weeks after roasting, so the foil bags should have one-way exhaust valves so that they don't expand. Coffee is often at its best the day after it is roasted; therefore, beans roasted that same day are not an absolute requirement, though it will mean that they'll be usable for a longer period. Investigate roasters who sell through the mail or over the Internet; there are many roasters who will ship beans they day they are roasted.

Grind your own coffee. If you are able to find a source for freshly roasted beans but then grind the whole package at the point of purchase, you have effectively gone back to buying pre-ground coffee, and it will become stale by the end of the day you bring it home. If you are steadfast in not purchasing a grinder, accept that your coffee will be less than stellar; purchase as small a quantity of ground coffee as possible at a time and repackage as mentioned in the section on storage. This also applies to whole bean coffee: buy what you can use in about week, and no more than you can use within two weeks after the coffee was roasted.

2.1.1 What are coffee beans?
Coffee beans are the seeds of the coffee "cherry"; two seeds normally grow within each cherry. On the tree, the beans are covered by the silverskin (a vestigial remainder of the fruit's development, also called the spermoderm). The silverskin is covered by a parchment skin (the endocarp), which is covered by a slimy layer (the parenchyma), surrounded by a thin layer of pulp (the mesocarp), all covered by an outer skin (the exocarp). These layers must be removed prior to roasting, though some silverskin often remains attached.

2.1.2 Arabica and robusta
All coffee beans come from plants in the genus Coffea. Although there are thousands of species of plants within this genus, with tremendous variance in size and shape, only two are of commercial importance: Coffea arabica, and Coffea canephora, the latter more commonly called robusta, after a prime variety. A third species, Coffea liberica has found some localized production in Liberia, but it is of minor significance in the global market.

Arabica is genetically distinct: it has four sets of chromosomes, whereas robusta, and liberica each have two.

Sensory descriptions

On average, a robusta will be harsher. One importer likened a particularly bad origin to dung, though very fine robustas can, potentially, compare favorably to a quality arabica. Premium robustas are essentially reserved for espresso blends, where they are primarly used to greatly improve the crema and to add a certain bite to the shot. The difficulty is in finding an exceptional robusta; growers and processors are often not willing to dedicate as much effort to robusta as they are to arabica, since the only potential market is for those blends. Robustas are rarely sold straight; instead, in addition to premium robustas used in espresso blends, poor quality robustas may be added to freeze-dried coffees or to coffee-flavored frozen drinks where the sugar and cream overwhelm the off-notes. Robusta has notably more caffeine than arabica.

Production Conditions
In subtropical conditions, arabaics best thrive at lower altitudes, from as low as 1000 feet in the Kona region of Hawaii, to about 4000 feet in regions of Mexico and a few other locations. Closer to the equator, coffee tends to thrive at higher altitudes, from 3500 feet up to 9500 feet in Ecuador, though the latter is exceptional, and the usual ceiling is closer to 6000 feet. Both frost and high heat can damage or kill the plants. Too much or too little rain can adversely effect fruit production; likewise, the soil must be moist but well-drained. Coffee plant naturally do well in well-lit but forest-shaded regions. Newer hybrids do well in full sun, but are controversial for other reasons (See What is "songbird friendly" coffee?.) Arabicas are not very resistant to insects or fungus, and there have been a few major scares where significant acreage was threatened by leaf rust (Hemileia vastatrix) or other pests. Lower altitude regions that aren't as well suited to growing arabicas are nevertheless used to grow poorer quality examples; these are often carelessly handled and sometimes generically referred to as Brazils. This is not indicative of origin: "Brazils" are not necessarily grown in Brazil, a country that also produces high quality coffee.

Robustas do well at lower altitudes, are more disease resistant, and yield more fruit. As a result, the overall cost per pound is lower than arabica.

In General
Over sixty-five percent of the coffee grown throughout the world is arabica, but much of it is unexceptional. On its own, the label "arabica" is no assurance of quality: you will need to know much more about it and find a reputable retailer who can provide much more information, and who has sampled ("cupped") each lot. As noted, although Brazil grows some excellent coffee, a sizeable portion of the arabica grown there is of quite poor quality, to the point where the coffee trade uses a particular term, "Rioy" (from Rio de Janeiro), to describe certain particularly harsh, pungent coffees.

As with most foods, although there are some objective factors, taste is ultimately subjective. While very few people will find Vietnamese robusta enjoyable, not everyone will agree that Jamaican Blue Mountain is the epitome of flavor. As a broad rule, all-arabica blends will considerably taste better, but a superior robusta may fare better than a poor quality arabica.

2.1.3 How important is the beans' country of origin?
The coffee's country of origin is largely a matter of subjective taste, and you will benefit by sampling a wide variety of origins and roasting styles. Origin is important in that the comparative bean flavor between growing regions, even within the same country, can be quite different. As a result, it is difficult to make sweeping generalizations about the coffees in any particular region.

2.1.4 What's the difference between dry processing and wet processing?
This refers to how the pulp is removed from the bean.

Dry processing is the oldest method of processing coffee. The cherries are washed and then spread out on drying racks to dry in the sun for several weeks, or alternatively, are dried by machine. During this drying process, the pulp ferments, lending a particular taste to the bean. How the coffee is handled during drying—whether sun-dried coffee is protected against adverse weather or temperature, the machine driers' temperature, etc.—effects the eventual quality and flavor of the bean. After the beans are dried, they are machine processed to remove the dried outer layers.

Wet processed beans have their outer skins removed by machine processing, then the fruit with the exposed pulp is allowed to ferment in tanks where bacteria and naturally occurring enzymes consume the pulp. The beans are then washed and dried, also either by sun or machine, and the dried beans are then milled to remove the remaining layers.

Some beans are semiwashed. The outer skins are removed, but the pulp is allowed to dry on the beans. The beans are then hulled as in the dry process, but the pulp is usually wetted as part of this step.

Broadly put, many feel that dry processing enhances body and complexity, whereas wet processing enhances clarity and acidity. Semiwashed is an attempt to combine these enhancements.

2.1.5 Jamaican Blue Mountain
Often used as a synonym for coffee excellence, Jamaican Blue Mountain refers to a specific region on the island of Jamaica: the Blue Mountains, of which Blue Mountain Peak is the highest point on Jamaica at 7,402 feet. Only coffee grown on certain estates may be called "Blue Mountain": Wallenford, Mavis Bank, Silver Hill, and Moy Hall registered the rights to call their product Blue Mountain, and Old Tavern Estate was in recent years awarded the right to use the name. The sale, roasting, and export of Blue Mountain coffee is strictly controlled by the Jamaican government and the Coffee Industry Board.

Jamaican Blue Mountain (or JBM) is quite expensive, often $30 a pound or more, but the general consensus of professional roasters today is that the brand rides on its reputation and mystique, and that the taste of the modern day JBM is not as good as the JBM of the 1970s or 1960s.

Further, there is a considerable quantity of counterfeit JBM out there — not surprising, considering that the quantity sold each year worldwide handily outstrips the actual yearly production. Not all of it is outright counterfeit — some is simply misleading: you may see "Jamaica Blue Mountain style" coffee, or "Jamaica Blue Mountain Blend." The former likely doesn't actually contain any JBM, and the latter need only contain as little as 5% authentic JBM to be called a JBM Blend. There is also Jamaica High Mountain, which refers to coffee grown by estates in the area that cannot use the JBM label. These may well be high quality coffees, but they should not cost nearly as much as true Jamaican Blue Mountain.

2.1.6 Kona
Hawaii is the only state in the United States that grows coffee, though several US territories also grow it. Compared to Jamaican Blue Mountain, Kona's lower per-pound price yields a coffee whose quality is arguably more commensurate with its price.




2.1.7 What is Mocha-Java?
Mocha is a port in Yemen, near the southern end of the Red Sea, though it has been of negligible use as a port since the late 1800s. Java is an island in Indonesia. Mocha referred to those beans shipped from the port of Mocha, and Java to those beans grown on Java. Mocha Java was the world's first successful commercial blend of two coffees. It is commonly believed that roasters in the mid to late 1800s recognized that certain aspects of the Yemeni bean worked in harmony with the Java beans. On the other hand, it merely have been expedient to mix these two widely-known coffees.

Unfortunately, the original Mocha-Java blend that was a commercial success over 120 years ago is lost to us today because of a blight of coffee leaf rust (Hemileia vastatrix, or "la roya") that wiped out the old Java stock of coffee trees prior to the start of the 20th century. Eventually the island's coffee tree population was replanted, but coffee historians agree that the bean from the new trees never equaled the taste profile of the old one, and the original Mocha-Java blend is forever gone. Today, highly skilled roasters can emulate the Mocha-Java blend taste, but they often pick beans that are neither Yemeni Mocha nor Indonesian Java to achieve it. Since we can't truly know how that original blend tasted, using non-Yemeni and Indonesian coffees is not necessarily inauthentic. So why does "mocha" refer to coffee with chocolate?
Purportedly, resellers unable or unwilling to purchase true Mocha coffee began adding small quantities of chocolate to other beans and reselling it as Mocha, in an attempt to duplicate the subtle flavor of the real bean. A alternate explanation that has been offered is that a combination of coffee and chocolate was called "mocha" in honor of the well-regarded coffee that it was reminiscent of. This practice was later applied to any coffee to which chocolate has been added.

2.1.8 Why are some coffees aged?
Unroasted coffee beans that are properly stored will change their taste profile. Acidity decreases and the perceived body deepens, while certain defects can become less apparent. Those coffees given the appellation "aged" are usually held for a number of years under carefully controlled conditions, and may have extraordinarily rich bodies. However, some aged coffees simply taste old and flat. Make sure you buy aged coffee from a reputable dealer who has sampled ("cupped") that particular batch.

2.1.9 What's a monsooned coffee?
Monsooned coffees have been held in open-sided warehouses and exposed to the steady, damp monsoon winds. In a matter of weeks, the beans yellow, and gain a flavor reminiscent of, but distinct from aged coffees. By far the most common monsooned coffee is Indian monsooned Malabar. Again, buy from a retailer who is personally familiar with the particular batch of coffee you are considering purchasing. Monsooned coffee isn't for everyone, but it should be sampled.

2.1.10 What is a "peaberry"?
The normal development of the coffee cherry creates two seeds, which grow with their flat sides facing each other. Infrequently, one seed fails to thrive and a single, round bean fills the available space. Often sorted out and sold separately, these single beans are known as "peaberries" and are technically mutant growths. Some in the coffee trade argue that peaberries have a richer, more concentrated flavor than normal beans, but others claim that they cannot discern a difference in a blind cupping. Today, the most famous peaberry is probably Tanzanian, where the plants seem more prone to producing peaberries than anywhere else. But you can often find peaberry-only versions of Kona, Kenyan AA, Java, and other types of "famous name" coffees if you shop around long enough at specialty coffee houses and online shops.

2.1.11 What are "espresso beans?"
Although frequently used to refer to a dark, oily roast, there really is no such thing as "espresso beans" or "espresso roast." These names refer to different blends of coffee varieties and roasts, created with the intent of achieving an optimal espresso; no two blends are likely to be the same. Often, the goals are different: optimally, espresso intended for milk-based drinks will have different taste criteria than espresso intended to be drunk straight; the former needing aspects that can cut through the taste of the milk. Roasters will often have their own proprietary blends with closely guarded compositions.

2.2 What is the difference between the various decaffeination processes?
There are three processes for decaffeinating coffee: solvent, carbon dioxide, and water process. Regardless of technique, all coffees are decaffeinated prior to roasting.

2.2.1 Solvent (European) process
Technically speaking, all of the processes are solvent-based, since a solvent merely refers to a substance that is capable of dissolving another substance. However, in this field the common usage is to use the terms "solvent" or "chemical solvent" to refer to the process that uses either methylene chloride (dichloromethane) or ethyl acetate. There are two ways in which solvents are used to remove caffeine from coffee: a direct process, and an indirect process. The steps are essentially the same whether methylene chloride or ethyl acetate is used.

In the direct process, the beans first are steamed, which causes them to swell and become somewhat more permeable. The beans are then put into contact with the solvent, under pressure, for a specified period of time, which will, by and large, selectively extract the caffeine. The solvent is then processed to remove the caffeine, and can be reused for the next batch. The beans are usually steamed again after treatment in order to remove the remaining solvent.

In the indirect process, the beans are soaked in hot water, which removes almost all of the soluble compounds, including the caffeine. The water is drained off and mixed with the solvent, which bonds with the water. The solvent/caffeine mixture, less dense than the water, floats to the surface where it can be removed. The water and beans are mixed together, and the beans soak up most of the lost flavors.

Ethyl acetate is a substance that occurs naturally in many fruits and other foods, thereby earning the "natural" label, and it is is marketed towards those who are concerned that methylene chloride may have adverse health effects. Note that although ethyl acetate occurs in nature, the substance used for decaffeination likely has an industrial origin, thereby undercutting the "natural" appellation. The US Food and Drug Administration has labeled ethyl acetate as "Generally Recognized as Safe " (GRAS).

The dangers of methylene chloride decaffeination are widely debated: the World Health Organization found the main toxic effects of the chemical itself (without evaluating the decaffeination process) to be reversible central nervous system depression and carboxyhaemaglobin formation. Additional effects reported were liver and renal dysfunctions, hematological effects, and neurophysiological and neurobehavioral disturbances. The studies were not able to make definitive conclusions regarding any links between methylene chloride exposure and cardiovascular disease or cancer. (The WHO Environmental Health Criteria Series, volume 164.)

However, processing virtually eliminates any residual solvent content, and levels cannot exceed regulated levels. Methylene chloride evaporates at 104 degrees F (40 degrees C), and so would not survive the roasting process.Though the chemical itself may be dangerous, there do not appear to be any tests that found residual methylene chloride in decaffeinated coffee, and it is also GRAS for this purpose.

2.2.2 Water Process
The process is similar to the indirect solvent process, with a few twists. First, activated charcoal, rather than solvents, removes the caffeine from the water. Second, rather than recombining the water with the beans, the first batch of beans is thrown out and the water is combined with a new, untreated batch of beans. The theory behind this is that since the water is already saturated with every dissolvable compound except for caffeine, only the caffeine in the beans will dissolve, leaving the flavor intact. Since the water is used over and over, some flavors may become commingled between batches.

The most well known variant is the Swiss Water® Process, the first economically viable water decaffeination process and the current industry leader. The company asserts that it has made substantial improvements to reduce the cross-batch contamination phenomena, to the point where they are not an issue.

2.2.3 Carbon Dioxide Process, Sparkling Water Processes
When certain gasses are compressed above certain critical pressures and critical temperatures (73 bar/1059 psi and 88 degrees Fahrenheit in the case of carbon dioxide), they are known as supercritical gas fluids, exhibiting traits of both gas and liquid. In both of these processes, supercritical carbon dioxide is combined with the beans, where it combines with the caffeine. The carbon dioxide is then isolated and filtered to remove the caffeine. In carbon dioxide process this is done with activated charcoal; in sparkling water process, the carbon dioxide is mixed with water, which filters out the caffeine.

2.3 Flavor terms
Flavor descriptions are inherently subjective—not surprising, considering how subjective taste can be. Unlike other sensory descriptions that have relatively objective descriptions (loud, soft, furry, scaly), taste (and smell) is often hard to describe.

Flavor terms can be divided into roast related descriptors and descriptors related to the bean variety (though this division is not a standard one). The roast related flavors refer to those characteristics imparted to the bean as a result of the roasting process. Varietal and processing terms refer to those aspects that are inherent in bean, or imparted as a result of the green bean's pre-roast processing. Roasting can substantially affect the intrinsic flavor and aroma of the bean; roasters will act in order to balance this and to enhance the beans' inherent profile. One further factor is preparation method; this can drastically change the coffee's character.

Related both to the roast and to variety. This term is akin to the description of acidity in wine, not to acid content. Indeed, retailers may avoid using this term in order to avoid confusion, and rely on terms such as "bright" or "lively." Acidity is more of a sensation than a taste, and is experienced on the tip of the tongue and/or the roof of the mouth. During roasting, acidity varies in an approximately inverse relation to body or bittersweet aspects; as the degree of roast increases, perceived acidity decreases. Coffees without acidity tend to taste flat, lacking a pleasant palate-cleansing aspect. Acidity can often have wine-like aspects, especially in many Kenyan coffees, or can come across as citrusy. When acidity is extreme, it can feel astringent, as if the moisture has been sucked from your mouth.

Related to both roast and variety. Most of our taste perception comes from our sense of smell, so the volatile aromatics emitted from brewed coffee play an important role in its taste. Aroma develops during roasting, but as the roast starts becoming dark, the carbonized sugars become dominant.

Baked or Bready
A roast related term. Baked coffee is flat, with little aroma; typically the result of an insufficiently high roasting temperature over too long a period of time. In other words, if the heat applied to the unroasted coffee is too low, the physical and chemical changes do not occur in a desirable fashion.

Roast and variety related. The pleasing combination of multiple characteristics, none overpowering.

Roast and variety related. Body is a textural quality, a perception of viscosity or fullness on the tongue; one roaster has likened it using your tongue as a weight scale. Body develops with the degree of roast, falling off sharply with over roasted coffee, but it can also vary by origin. Distinguish between body and the "thickness" imparted by some brewing methods, like coffee from a press, where fine particulates remain suspended, or espresso, which contains emulsified coffee oils. Underextracted coffee will also have a defectively light body.

Roast and preparation related. This is not always a defect; up to a point, it can be desirable. Robusta is more bitter than arabica, but mild coffees can become bitter if over roasted or over extracted during brewing.

Roast related term. Often mischaracterized as "strong," the bittersweet aspect is created by the caramelization of sugars in the bean. The longer the coffee is roasted, the greater the caramelization, until at last the sugars are completely burned, giving the coffee a taste akin to charcoal (see next entry).

When very mild, this aspect may be desirable for cutting through drinks containing a lot of milk and/or sugar, though there are those who like it in a straight cup. When overdeveloped, it is the flat taste of charcoal; this taste can be overwhelming.

Clean-tasting coffees are free of defects or undesirable distractions.

Complexity simply means that the cup has many elements--aromas, textures, and tastes--apparent at once, or in succession. Since it is rare to fnd all of the desirable elements in a single origin, roasters often roast different coffees to achieve a varied profile.

Earthy, or Natural
Within limits, this can be a pleasant note, but more commonly a defect in which the brewed coffee has an aftertaste akin to freshly turned soil. Commonly relates to poor processing, one way this defect can occur is when the beans absorb flavor from the dirt on which they were spread to dry. In more muted degrees, this quality can add interesting notes to a coffee.

Lacking in taste or aroma; low in acidity. Often occurs when the coffee goes stale.

Processing related. The aroma and taste of hay, or a newly mown lawn. This can result from prematurely picked cherries.

Moldy, mildewy ; often the result of some improper storage conditions. Improper aging also can cause mustiness, while proper aging can contribute a desirable flavoring aspect (see Section 2.1.7)

Rioy (REE-oh-ee)
A harsh, medicinal quality, the term derives from a reference to low quality coffees from Brazil (i.e., Rio De Janiero). See also here.

Unpleasantly acrid or sour, as if contaminated by vinegar. This taste can occur in low-growing, unwashed coffees, but commonly occurs in under roasted coffees, or even properly roasted beans that were then brewed with water that was too cool.

2.4 Roast names
There is little consistency in roast descriptions; one roaster's full city roast is another's espresso roast. In recent years, regional variations have blurred. For commercial reference, an objective reference has been established by the SCAA called the Agtron gourmet scale, ranging from #95 (lightest) to #25 (darkest). A sample of roasted coffee is illuminated, and the reflectance of certain near-infrared wavelengths is measured; this closely determines the thermal absorbencies of the coffee. The machine that takes these measurements is quite expensive, so a less expensive alternative exists in the form of a series of color tiles that are compared to the roasted and ground beans.

Nevertheless, some generalizations can be made, though again the distinctions are, again, somewhat arbitrary:

Light Cinnamon
Light tan, dry, unpleasantly sour, little or no body. Reminiscent of cereal.

Slightly darker than light cinnamon, but the taste and texture is little different.

Light or New England
Light brown, sourness has decreased, but the cereal taste is largely gone.The name derives from its original use for inexpensive coffee in the eastern U.S.

Light to medium brown; once the predominant roast in the United States. Varietal variance distinct.

Viennese or Full City
Medium brown, the norm for most of the Northwestern US. Body, flavor, and aroma are quite balanced

Medium to dark brown with drops of oil on the surface, greater sweetness, carbonized sugars lend a caramel flavor; body exceeds acidity.

Surface is dark brown and lightly coated with oil; burnt notes become noticeable, acidity low.

Italian or Dark French
Almost black, with a lot of surface oil. Tasted clearly burnt; acidity and even body are almost undetectable.

Oily and black and very oily; overwhelming charcoal taste.

2.5 Coffee bean size classifications
Coffee is commonly classified based upon screen size, i.e., the size of the holes of a screen sorting system. The screen holes are based on sixty-fourths of an inch, so a #15 is 15/64"; this can also be given in metric equivalents. If nothing else, classification helps ensure bean size uniformity which makes roasts more even (though some roasters eschew uniformity for complexity, at least for certain bean varieties). Additionally, there is a belief that larger size beans have a better taste profile, though that is by no means a uniform rule, especially when comparing different varieties of coffee (there are many inherently smaller varieties that have a "richer" taste than some larger varieties)

In addition to the screen size classifications, there are also regional classifications; for example (from smallest to largest within each series): Terceras, Segundas, and Superior (Central American and Mexican); Excelso or Supremo (Colombia); C to B to AA (African and Indian); and No. 1, Fancy, and Extra Fancy (Kona). A single "named size" may translate to different screen size measures, depending upon the intended export destination (that is, the retail market).Named classifications may have other differences as well: the Kona rankings also account for the average defects per pound.

Size grading is usually done for export purposes, with the lowest grade beans not considered exportable

2.6 What is a cultivar?
Also called a varietal, a cultivar a variety of a plant that has been developed by selective breeding. There are two naturally occurring varieties of arabica coffee, bourbon and typica (the latter also simply called Arabica). Bourbon derives its name from the island of Reunion, formerly named Bourbon, where the variety (grown from transplanted trees) was first identified. Other cultivars in use today are generally derived from these two. Some other cultivars are: Mundo Novo, Maragogype, Catimor, Catuai, Caturra, Variedad Colombia, Pacas, and Blue Mountain . This is not an exhaustive list.

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©2003, 2004, 2005, 2006 by Scott Rothstein
