Composition of Brews. The real tests of the comparative values of different methods of brewing are the flavor and palatibility of the drink, in conjunction with the number of cups of a given strength which are produced, or the relative strengths of brews of the same number of cups volume. Chemical analysis has not yet been developed to a stage where the results obtained with it are valuably indicative. Caffeol is present in quantities so small that no comparative results can be obtained. "Caffetannic acid" determinations are practically meaningless. This compound is of so doubtful a composition and physiological action, and the methods employed for its determination are so indefinite as to interpretation, as to render valueless any attempts at comparison of relative percentages. The only accurate analysis which can be made is that for caffein.
Much advertising emphasis has been placed on the small amount of caffein extracted by some devices. What is one of the main reasons for the consumption of coffee? The caffein contained therein, of course. So that if one device extracts less caffein than another, that fact alone is nothing in favor of the former. If the consumer does not want caffein in his drink there are caffein-free coffees on the market.
Fine-Meal Grind Under the Microscope
The coffee liquor acts on metals in such a manner as to lower the quality of the drink, so that metals of any sort, and by all means, irons, should be avoided as far as possible. Instead, earthenware or glass, preferably a good grade of the former, should be employed as far as possible in the construction of coffee-making devices.
Of the various metals, silver, aluminum, monel metal, and tin (in the order named) are least attacked by coffee infusions; and besides these, nickel, copper, and well enameled iron (absolutely free from pin holes) may be used without much danger of contamination. Rings for coffee-urn bags should be made of tinned copper, monel metal, or aluminum. Even if coffee be made in metal contrivances, the receptacles in which it stands should be made of earthenware or of glass.
Painstaking care should be given to the preservation of the coffee-makers in a state of cleanliness, as upon this depends the value of the brew. Dirt, fine grounds, and fat (which will turn rancid quickly) should not be allowed to collect on the sides, bottom, or in angles of the device difficult of access. Nor should any source of metallic or exterior contamination be allowed to go uneliminated.
The Perfect Cup of Coffee
Lovers of coffee in the United States are in a better position to obtain an ideal cup of the beverage than those in any other country. While imports of green coffee are not so carefully guarded as tea imports, there is a large measure of government inspection designed to protect the consumer against impurities, and the Department of Agriculture is zealous in applying the pure food laws to insure against misbranding and substitution. The department has defined coffee as "a beverage resulting from a water infusion of roasted coffee and nothing else."