The first step in testing coffee is to compare the appearance of the green bean of a chop with a sample of known standard value for that particular kind of coffee. The next step is to compare the appearance when roasted. Then comes the appearance and aroma test, when it is ground; and finally, the most difficult of all, the trial of the flavor and aroma of the liquid.
Naturally the tester gives much care to proper roasting of the samples to be examined. He recognizes several different kinds of roasts which he terms the light, the medium, the dark, the Italian, and the French roasts, all of which vary in the shadings of color, and each of which gives a different taste in the cup. The careful tester watches the roast closely to see whether the beans acquire a dull or bright finish, and to note also if there are many quakers, or off-color beans. When the proper roasting point is reached, he smells the beans while still hot to determine their aroma. In some growths and grades, he will frequently smell of them as they cool off, because the character changes as the heat leaves them, as in the case of many Maracaibo grades.
After roasting, the actual cup-testing begins. Two methods are employed, the blind cup test, in which there is no clue to the identity of the kind of coffee in the cup; and the open test, in which the tester knows beforehand the particular coffee he is to examine. The former is most generally employed by buyers and sellers; although a large number of experts who do not let their knowledge interfere with their judgment, use the open method.
In both systems the amount of ground coffee placed in the cup is carefully weighed so that the strength will be standard. Generally, the cups are marked on the bottom for identification after the examination. Before pouring on the hot water to make the brew, the aroma of the freshly ground coffee is carefully noted to see if it is up to standard. In pouring the water, care is exercised to keep the temperature constant in the cups, so that the strength in all will be equal. When the water is poured directly on the grounds, a crust or scum is formed. Before this crust breaks, the tester sniffs the aroma given off; this is called the wet-smell, or crust, test, and is considered of great importance.
Of course, the taste of the brew is the most important test. Equal amounts of coffee are sipped from each cup, the tester holding each sip in his mouth only long enough to get the full strength of the flavor. He spits out the coffee into a large brass cuspidor which is designed for the purpose. The expert never swallows the liquor.
Cup-testing calls for keenly developed senses of sight, smell, and taste, and the faculty for remembering delicate shadings in each sense. By sight, the coffee man judges the size, shape, and color of the green and roasted bean, which are important factors in determining commercial values. He can tell also whether the coffee is of the washed or unwashed variety, and whether it contains many imperfections such as quakers, pods, stones, brokens, off-colored beans, and the like. By his sense of smell of the roast and of the brew, he gauges the strength of the aroma, which also enters into the valuation calculation. His palate tells him many things about a coffee brew—if the drink has body and is smooth, rich, acidy, or mellow; if it is winy, neutral, harsh, or Rioy; if it is musty, groundy, woody, or grassy; or if it is rank, hidey (sour), muddy, or bitter. These are trade designations of the different shades of flavor to be found in the various coffees coming to the North American market; and each has an influence on the price at which they will be sold.