As a result of our experiments with different ways of roasting and brewing coffee, we have found the following plan to be the most convenient and the best: the coffee will taste the same every time and it will taste good. If a good berry be properly roasted and the infusion be of the proper strength, good coffee must result. A Mocha berry should be selected and roasted seven or eight pounds at a time in a cylindrical drum. After roasting it should be placed in a stone jar with a mouth three inches in diameter. The jar should be closed air-tight. This will furnish two cups of coffee daily for six months. A quart should be taken from the jar at a time and ground. The ground coffee should be kept in covered glass jars.
The best coffee pot was found to be the common biggin having an upper compartment with a perforated bottom upon which to place the coffee. To make one cup of this infusion, place half an ounce of ground coffee in the upper compartment and six fluid ounces of water into the bottom. Put the biggin over a gas lamp. After three minutes the water will boil. When steam appears, take the biggin from the fire and pour the water into a cup and thence immediately into the top of the biggin where it will extract the berry by replacement. (Here follows an experiment.)
This experiment shows that loss of weight is no criterion that coffee is properly roasted, neither is the color (by itself) nor the temperature, nor the time.
Next we experimented to ascertain whether the aroma developed by roasting coffee and which is lost might not be collected and added to the coffee at pleasure. An attempt was made to drive the volatile oils from roasted coffee by steam and make a dried extract of the residual coffee to which the oils were to be later added. Two attempts were made and both failed. It appears that but a small quantity of the aroma is lost in roasting and that is mixed with bad smelling vapors from which it is impossible to free it.
Then we tried to make a potable coffee by making an aqueous extract of raw coffee, evaporating to dryness and roasting the residue. (Here follows the experiment.)
This also was unsuccessful. The great trouble here is a dark shiny residue, which, while tasteless, is very disagreeable to look at. In the preparation of coffee by boiling, two and a half times as much matter is extracted as by biggin.
The proper method of roasting coffee is as follows: It should be placed in a cylinder and turned constantly over a bright fire. When white smoke begins to appear, the contents should be closely watched. Keep testing the grains. As soon as a grain breaks easily at a slight blow, at which time the color will be a light chestnut brown, the coffee is done. Cool it by lifting some up and dropping it back with a tin cup. If it be left to cool in a heap there is great danger of over-roasting. Keep the coffee only in air-tight vessels. Measure the infusions, a half ounce of coffee to six ounces of water per cup.
All "extracts of coffee" are worthless. Most of them are composed of burned sugar, chicory, carrots, etc.
In 1883, an authority of that day, Francis B. Thurber, in his book, Coffee; from Plantation to Cup, which he dedicated to the railroad restaurant man at Poughkeepsie, because he served an "ideal cup of coffee", came out strongly for the good old boiling method with eggs, shells included. This was the Thurber recipe:
Grind moderately fine a large cup or small bowl of coffee; break into it one egg with shell; mix well, adding enough cold water to thoroughly wet the grounds; upon this pour one pint of boiling water: let it boil slowly for ten to fifteen minutes, according to the variety of coffee used and the fineness to which it is ground. Let it stand three minutes to settle, then pour through a fine wire-sieve into a warm coffee pot; this will make enough for four persons. At table, first put the sugar into the cup, then fill half-full of boiling milk, add your coffee, and you have a delicious beverage that will be a revelation to many poor mortals who have an indistinct remembrance of, and an intense longing for, an ideal cup of coffee. If cream can be procured so much the better, and in that case boiling water can be added either in the pot or cup to make up for the space occupied by the milk as above; or condensed milk will be found a good substitute for cream.