FoodNet

Foods, their selection and preparation

1935

Page 309

Presented as published in 1935. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
Diagrams of Coffee Berries • (At left) Coffee berry halved, showing single coffee bean. (At right) Coffee berry with half of fruit pulp re¬ moved, showing two coffee beans in parchment coverings The first step in the preparation of coffee beans is the removal of the pulp. This may be done either by mechanical means or by soaking. The next step is the fermentation, which helps to develop the proper flavor in the berries and reduces the sugar present. After fermentation, the beans are washed and dried, then cured while still in the parchment lining. After curing, the hulls are removed. Then the beans are put through a machine which removes all foreign material and sorts them according to size. In this form the coffee is shipped. The green beans have a yellowish- green color which deepens with the age of the coffee. Coffee must be roasted before it is ready for use. This may be done by the distributor, or by the retailer if he has a large coffee trade. Roasting is an extremely important step in the preparation of the coffee bean. Green coffee has little aroma and flavor. Proper roasting develops the full aroma and flavor, and influences the physiological effects of the coffee. Changes in the fat content of the bean cause the formation of caffeol , the vola¬ tile oil that gives coffee its aroma and flavor. Carbon-dioxide gas is developed along with the caffeol. The color of the coffee changes during roasting from green to brown, because of the formation of caramel from the sugar in the bean. The color is determined by the amount of caramel formed and this varies with the temperature and time of roasting. There are "light” roasts, "medium” roasts, "high” or "dark” roasts, and Italian or French roasts, with colors varying from cinnamon to chocolate brown. Coffees from different sources are usually blended before being placed on the market, but this should not be done before roasting, since the different coffees need to be treated differ¬ ently during the roasting process. Composition and Use. The composition of the coffee berries is of little interest, but that of a cup of coffee is of importance to those who prepare or drink it. The beverage contains only the portion of the bean which is soluble in water. The quality of a cup of coffee is determined not only by the kind of coffee, but by the way it is handled, the temperature at which it is roasted, in what condition and for how long it is stored, to [335] what fineness it is ground, and last, but not of least importance, how it is made. The substances which are present in varying amounts in a cup of coffee are tan¬ nin, caffeine, caffeol, caramelized carbo¬ hydrates, and carbon dioxide. The charac¬ teristics of these substances will determine the quantities of them which are obtained from various methods of handling and pre¬ paring coffee. The tannin in coffee, and also that in tea, is slowly dissolved in hot water. The amount which goes into solution depends upon the length of time the water and coffee are in contact with each other and upon the tem¬ perature of the water. It is more soluble at the boiling temperature than just below boiling. Caffeine is the alkaloid which gives the stimulating quality to coffee. The average cup of coffee, as made in the United States, contains from 1.5 to 1.75 grains of caffeine.