Ask the average coffee drinker where coffee comes from and he’ll probably say “South America.” Coffee actually originated in Ethiopia, where the coffee plant grows naturally. Coffee has been drunk in Arabian countries for centuries, but was only introduced to Europe in the mid1600s. Plantations established in European colonies in Indonesia, the West Indies and Brazil soon made coffee cultivation an important part of those region’s economies.
Today, the coffee bean is the world’s most valuable agricultural commodity, and Latin America and Africa produce most of it. (Brazil is the individual country that produces the most.) North America imports more than anyone else, not surprising considering the average American drinks 3 1/3 cups of the stuff a day. (Which means somebody must be drinking 6 2/3 cups a day, because most days I don’t drink any!)
The coffee plant is an evergreen shrub with waxy leaves that grows in hot, moist climates. It’s five to eight years old before it finally bears fruiit: small red “cherries,” each containing two coffee seeds, or “beans.” Once a tree starts bearing fruit, it produces only about two kilograms of fruit a year, which in turn yields less than half a kilogram of coffee. This means it takes literally billions of coffee plants to satisfy the world’s thirst.
Although there are many varieties of coffee plant (and wild strains are still harvested in its homeland of Ethiopia), two species, arabica and robusta, account for 99 percent of the world’s output. The robusta plant is hardier, less likely to fall victim to bad weather or disease, but its beans produce coffee with a harsher taste and so tend to end up in instant coffees and bargain brands. Arabica beans are used for premium coffees.
The coffee cherries are only picked when fully ripe, which means they must be picked by hand by knowledgable pickers. One reason arabica coffee costs more is that, while robusta cherries remain on the tree after they ripen, arabica cherries fall to the ground and spoil. This means arabica trees must be very carefully watched and picked over several more times than robusta trees.
Once the cherries are picked, there are two ways of removing the pulp from around the beans: either the cherries are dried, and then the pulp removed, or the cherries are washed and pulped to separate the beans. The two methods produce distinctive flavors. Differences in soil and climate also affecte the flavor of coffee beans: the best coffee is grown at altitudes between 1,000 and 2,000 metres in rich volcanic soil. In fact, just about every step in the processing of coffee affects the flavor, which is why making fine coffee has been likened to making fine wine–and why there are so many kinds of coffee to choose from.
Once dried, the gray-green beans are sorted, bagged, graded by type and quality and shipped to processors, usually in the importing countries. The next step is roasting, which, again, helps determine the flavor of the final cup of coffee. Beans roasted for a long time (those destined to make espresso, for instance) are stronger and mellower than those that are lightly roasted, but beans that are roasted too long can lose the best part of their taste up the chimney.
There are two ways of roasting coffee beans: continuous roasting, in which hot air at between 200 and 260 degrees Celsius is forced through a small quantity of beans for about five minutes, or batch roasting, in which much larger quantities are roasted for a longer time. After roasting the beans are usually ground and vacuum-packed in cans. Once a can has been opened, the flavor of the coffee deteriorates rapidly, which is why many coffee drinkers simply buy roasted beans and grind them at home.
The reason the flavor deteriorates rapidly is the same reason coffee has such a unique taste in the first place: it’s a complex mixture of more than 100 different chemicals, some aromatic, some bitter–proteins, starches, oils and more. Coffee smells wonderful when you open the can: but that smell is the smell of complex molecules breaking down and being released into the air, taking flavor with them. Oxygen also interacts with the oils in coffee, eventually turning them rancid.
Some instant coffee is made by spraying a fine mist of very strong coffee extract through a jet of hot air. The hot air evaporates the water in the extract, leaving behind dried coffee particles. Another method is freeze-drying, in which the water is removed with extreme cold instead of heat.
Caffeine can be removed by coffee by processing the green bean in a bath of methylene chloride, then steaming the bean to remove the methylene chloride. More recently, caffeine has been removed by using steam alone, which is less environmentally harmful.
Speaking of caffeine, it’s coffee’s best-known ingredient. It’s a mild stimulant that acts on the central nervous system, improving attention and concentration, strengthening muscles and reducing fatigue. It’s found in more than 60 plants, including coffee and cocoa beans, tea leaves and cola nuts, and is added to many soft drinks and over-the-counter drugs. A cup of coffee, however, usually has the highest concentration of any of these things (except maybe drugs). Too much coffee can cause “coffee nerves” — jumpiness, trouble sleeping, upset stomach, heart palpitations, diarrhea. These effects are easily countered by drinking less coffee.
Recently, however, there have been a number of studies on the effects of coffee consumption on health that suggest more serious effects. Studies are continuing, but most of the “coffee scares” of recent years have been countered by further research. For example:
Some studies have found ties between high cholesterol and coffee (even decaffeinated coffe), but others have not. The most recent report from the Institute of Food Technologists states that “there continues to be no evidence to suggest that moderate caffeine intake is a causative factor in cardiovascular disease.”
Pregnant women have been warned against drinking very much coffee since 1980, when a study that involved force-feeding caffeine to pregnant rats produced baby rats missing toes. However, the human equivalent to the amount of caffeine that produced the birth defects would be 87 cups of strongly brewed coffee a day.
Possible links between cancers of the bladder and pancreas and coffee consumption have been reported for years, but the links are tenuous at best and further studies have mostly discounted them. Most experts don’t feel the links are strong enough to warrant stopping people from drinking coffee.
A study a couple of years ago found that blood pressure declined in people who were drinking three to six cups of coffee a day and then stopped. However, a cardiologist from the Mount Sinai Medical Center pointed out that the same statistical changes in blood pressure could be produced by standing up from a chair.
It all boils down to good old common sense: coffee (and everything else) in moderation.
Finally, some tips from Consumer Reports magazine on making the perfect cup of coffee:
Start with whole coffee beans. Grind only as much as you need, and freeze unused coffee, beans or ground, in a dry, airtight container.
Always use cold, fresh water–bottled, if you don’t care for the taste of your tap water (hard to imagine in Regina!)–and very clean utensils. (Oils from previous coffee-making can spoil the flavor of your new batch.) Don’t stint on the coffee: you’ll get a better cup by making it strong and then diluting it with hot water than by using too little coffee. The best flavor is what the hot water releases first: two little coffee in too much water releases more bitter compounds.
Prepare the coffee with water just below boiling, and serve it promptly. Coffee will keep its taste well in a thermos for several hours, and you can also warm it in a microwave, but keeping it on a low burner too long or reheating or boiling it destroys the delicate chemical balance, driving off the better-tasting molecules and leaving behind those that will make the coffee taste as bad to you as it does to those of us who don’t much like the stuff anyway.