All About Coffee

Just here, in order to assure a better understanding of the subject, it may be well to clear up sundry misconceptions regarding the words percolation, filtration, decoction, infusion, etc., by the simple expedient of definition.

A decoction is a liquid produced by boiling a substance until its soluble properties are extracted. Thus the coffee drink was first a decoction; and a decoction is what one gets today when coffee is boiled in the good old-fashioned way--as "mother used to make it."

Infusion is the process of steeping--extraction without boiling. It is extraction accomplished at any temperature below boiling, and is a general classification of procedure capable of sub-division. As generally and correctly applied, it is the operation wherein hot water is merely poured upon ground coffee loose in a pot, or in a container resting on the bottom of the pot. In the strictest sense of the term, an infusion is also produced by percolation and filtration, when the water is not boiled in contact with the coffee.

Percolation means dripping through fine apertures in china or metal as in De Belloy's French drip pot.

Filtration means dripping through a porous substance, usually cloth or paper.

Percolation and filtration are practically synonymous, although a shade of distinction in their meaning has arisen so that often the latter is considered as a step logically succeeding the former. Accomplishing extraction of a material by permitting a liquid to pass slowly through it is in fact percolation, whereas filtration of the resultant extract is effected by interposing in its path some medium which will remove solid or semi-solid material from it. Coffee-making practise has in itself so applied these terms that each is considered a complete process. Percolation is thus applied when the infusion is removed from the grounds immediately by dripping through fine perforations in the china or metal of which the device is constructed.

True percolation is not produced in the pumping "percolators" in which the heated water is elevated and sprayed over the ground coffee held in a metal basket in the upper part of the pot, the liquor being recirculated until a satisfactory degree of extraction has been reached. Rather, the process is midway between decoction and infusion, for the weak liquor is boiled during the operation in order to furnish sufficient steam to cause the pumping action.

Filtration is accomplished when the ground coffee is retained by cloth or paper, generally supported by some portion of the brewing device, and extraction effected by pouring water on the top of the mass, permitting the liquid to percolate through, the filtering medium retaining the grounds.

Patents and Devices

From the beginning, the French devoted more attention than any other people to coffee brewing. The first French patent on a coffee maker was granted in 1802 to Denobe, Henrion, and Rauch for "a pharmacological-chemical coffee making device by infusion."

In 1802, Charles Wyatt obtained a patent in London on an apparatus for distilling coffee.

The first French patent on an improved French drip pot for making coffee "by filtration without boiling" was granted to Hadrot in 1806. Strictly speaking, this was not a filtering device, as it was fitted with a tin composition strainer, or grid. It was very like Count Rumford's percolator announced six years later, as will be seen by comparing the two in chapter XXXIV.

In 1815, Sené invented in France his Cafetière Sené, another device to make coffee "without boiling."

About the year 1817, the coffee biggin appeared in England. It was simply a squat earthenware pot with an upper, movable, strainer part made of tin, after the French drip pot pattern. Later models employed a cloth bag suspended from the rim of the pot. It was said to have been invented by a Mr. Biggin; and Dr. Murray, of dictionary fame, seems to have become convinced of this gentleman's existence, although others have doubted it and thought the name was of Dutch origin, the article having been first made for Holland. It has been suggested that, in all probability, the name came from the Dutch word beggelin, to trickle, or run down. One thing is certain, coffee biggins came originally from France; so that if there was a Mr. Biggin, he merely introduced them into England. The coffee biggin with which Americans are most familiar is a pot containing a flannel bag or a cylindrical wire strainer to hold the ground coffee through which the boiling water is poured. The Marion Harland pot was an improved metal coffee biggin. The Triumph coffee filter was a cloth-bag device which made any coffee pot a biggin.

In 1819, Morize, a Paris tinsmith, invented a double drip, reversible coffee pot. The device had two movable "filters" and was placed bottom up on the fire until the water boiled, when it was inverted to let the coffee "filter" or drip through.

In 1819, Laurens was granted a French patent on the original pumping-percolator device, in which the water was raised by steam pressure and dripped over the ground coffee.

In 1820, Gaudet, another Paris tinsmith, invented a filtration device that employed a cloth strainer.

In 1822, Louis Bernard Rabaut was granted an English patent on a coffee-making device in which the usual French drip process was reversed by the use of steam pressure to force the boiling water upward through the coffee mass. Caseneuve, of Paris, was granted a patent on a similar device in France in 1824.

In 1825, the first coffee-pot patent in the United States was granted to Lewis Martelley on a machine "to condense the steam and essential oils and return them to the infusion."

In 1827, the first really practicable pumping percolator, as we understand the meaning today, was invented by Jacques-Augustin Gandais, a manufacturer of plated jewelry in Paris. The boiling water was raised through a tube in the handle and sprayed over the ground coffee suspended in a filter basket, but could not be returned for a further spraying.

In 1827, Nicholas Felix Durant, a manufacturer of Chalons-sur-Marne, was granted a French patent on a "percolator" employing, for the first time, an inner tube to raise the boiling water for spraying over the ground coffee.

In 1839, James Vardy and Moritz Platow were granted an English patent on a kind of urn "percolator", or filter, employing the vacuum process of coffee making, the upper vessel being made of glass.

By this time, the pumping percolator, working by steam pressure and by partial vacuum, was in general use in France, England, and Germany. And then began the movement toward the next stage in coffee making--filtration.

About this time (1840), Robert Napier (1791-1876) the Scottish marine engineer, of the celebrated Clyde shipbuilding firm of Robert Napier & Sons, invented a vacuum coffee machine to make coffee by distillation and filtration. The device was never patented; but thirty years later, it was being made in the works of Thomas Smith & Son (Elkington & Co., Ltd., successors) under the direction of Mr. Napier, the aged inventor. The device consists of a silver globe, brewer syphon, and strainer, as illustrated. It operates as follows: a half-cupful of water is put into the globe, and the gas flame is lighted. The dry coffee is put into the receiver, which is then filled up with boiling water. This will at once become agitated, and will continue so for a few minutes. When it becomes still, the gas flame is turned down, and clear coffee is syphoned over into the globe through the syphon tube, on the end of which, as it rests in the coffee liquid, there is a metal strainer covered with a filter cloth.

[Illustration: NAPIER VACUUM COFFEE MAKER]

[Illustration: NAPIER-LIST STEAM COFFEE MACHINE]

The Napierian coffee machine has enjoyed great popularity in England. The principle has in later years been incorporated in the Napier-List steam coffee machine for use in hotels, ships, restaurants, etc. Steam is used as a source of heat, but does not mix with the coffee. List's patent is for an improvement on the Napierian system and was granted in 1891.

It is related that shortly before he died, old Mr. Napier, at the termination of a dispute in Smith & Co.'s factory at Glasgow, where the device was being made under his instruction, said to old Mr. Smith:

"You may be a guid silversmith, but I am a better engineer."

[Illustration: FINLEY ACKER'S FILTER-PAPER COFFEE POT

SHOWING METHOD OF OPERATION]

In 1841, William Ward Andrews was granted an English patent on an improved pot employing a pump to force the boiling water through the ground coffee while contained in a perforated cylinder screwed to the bottom of the pot.

In 1842, the first French patent on a glass coffee-making device was granted to Madame Vassieux of Lyons.

Following this, there were numerous patents issued in France and England on double glass-globe coffee-making devices. They were first known as double glass balloons, and most of them employed metal strainers.

After this, there were many "percolator" patents in France, England, and the United States, some of which were for improved forms of the original drip method of the De Belloy device. Others were for the type of machine which came to be known as "percolators" because they employed the principle of raising the heated water and spraying it over the ground coffee in continuous fashion. The story is told in chronological order in the chapter on the evolution of coffee apparatus; so it is not necessary to repeat it here. Numerous filtration devices also were produced abroad and in the United States.

[Illustration: THE KIN-HEE POT IN OPERATION]

Among the percolators, those of Manning, Bowman & Co., and of Landers, Frary & Clark, became well known here. In the filtration field, the following attained considerable distinction: Harvey Ricker's Half-Minute pot, employing a cotton sack with re-inforced bottom, introduced about 1881; the Kin-Hee pot of 1900; Cauchois' Private Estate coffee maker, using Japanese filter paper, introduced in 1905; Finley Acker's percolator, introduced the same year, which also employed a filter paper between two cylinders having side perforations; the Tricolator, 1908; King's percolator, using filter paper, in 1912; and the "Make-Right", 1911, with its adaptation as presented in the Tru-Bru pot of 1920.

[Illustration: THE TRICOLATOR IN OPERATION]

The Make-Right was the invention of Edward Aborn, New York, and comprised two telescoping open wire frames, or baskets, with a flat piece of muslin between them. In the Tru-Bru pot, the same idea was employed, except that the wire frames were so constructed as to furnish four drip points to afford better distribution on the ground coffee and to lessen the time of filtration. There was also a porcelain top, to house and to raise the filtration device, above the brew with an opening through which the boiling water could be poured without exposing the ground coffee.

[Illustration: KING PERCOLATOR, AS APPLIED TO A HOTEL OR RESTAURANT URN]

Among later developments of the genuine percolator principle that have attracted attention in this country, mention should be made of the Phylax coffee maker, and the Galt pot.

In 1914-16, there was a revival of interest in the United States in the double glass-globe method of making coffee, introduced into France as "double glass balloons" in the first half of the nineteenth century. American ingenuity produced several clever adaptations, and several notable filter improvements. Advertising developed a great demand for glass percolators, as they were first called; but although five attained considerable prominence, only two survived and, at this writing, are still being manufactured. Both are double glass-globe filters employing a spirit lamp, gas, or electricity as heating agents.

[Illustration: THREE TYPES OF AMERICAN COFFEE MAKERS IN OPERATION

Left, Blanke's Cloth Filter--Center, Phylax--Right, Galt Vacuum device]

Within the last few years, it has become the fashion to obtain patents in the United States on "the art of brewing coffee", or the "art of making coffee". Instances are the patents issued to Messrs. Calkin and Muller. In the Calkin patent (the Phylax device illustrated at the top of this page) the "art" consists in controlling the flow of the boiling water by means of the number and spacing of the holes in the water-spreader, so as to restrict the volume and the speed, to effect a quick initial extraction; and then, by means of a new spacing of holes in the infuser, retarding the drip "to attain a prolonged extraction of the tannin and other elements of slow extraction and combining the liquids obtained during the initial and subsequent stages of the brew for attaining a balanced liquid extract."

[Illustration: HOW THE TRU-BRU POT OPERATES]

Muller's "art" (the apparatus is described in chapter XXXIV) consisted in so supplying and supporting the ground coffee in an urn that it is never again subjected to the "decoction" after having been exposed to the air and steam following the first application of the water.

In 1920, William G. Goldsworthy, San Francisco, was granted a United States patent on a process for preparing the beans for making the beverage. The process consisted of grinding the raw dried beans; then packing the ground product in non-combustible and non-soluble porous containers, which are securely closed to keep them unimpaired while the contained coffee is being roasted; and, after cooling, sealing them with gelatine. To brew, container and contents are dropped into a cup of hot water.

[Illustration: COFFEE-MAKING DEVICES USED IN THE UNITED STATES

1--Marlon Harland Pot; 2--Universal Percolator; 3--Galt Vacuum Process Coffee Maker; 4--Universal Electric Urn; 5--English Coffee Biggin (Langley Ware); 6--Universal Cafenoira (Glass Filter); 7--Vienna (Bohemian or Carlsbad) Coffee Machine; 8--Tru-Bru Pot; 9--Tricolator; 10--Manning-Bowman Percolator; 11--Blanke's Sanitary Coffee Pot; 12--Phylax Coffee Maker; 13--Private-Estate Coffee Maker; 14--American French Drip Pot; 15--Kin-Hee Pot; 16--Silex Opalescent Glass Filter; 17--French Drip Pot (Langley Ware).]

This brief review of the evolution of coffee brews shows that coffee making started with boiling, and next became an infusion. After that, the best practise became divided between simple percolation and filtration, which have continued to the present time. Boiling has also continued to find advocates in every country, even in the United States, where it seems to die hard, no matter how much is done to discredit it. Percolation devices are subdivided into the simple drip pots and the continuous percolation machines, as represented by numerous complicated and high-priced contrivances on the market. Gradually, however, true coffee lovers are realizing that the best results are to be obtained through simple percolation or simple filtration. There are good arguments for both methods.

Coffee Making in Europe in the Nineteenth Century

ENGLAND. We have noted Count Rumford's efforts to reform coffee making in England in the early part of the nineteenth century. Many other scientific men joined the movement. Among them was Professor Donovan, who in the Dublin Philosophical Journal for May, 1826, told of his experiments "to ascertain the best methods for extracting all the virtues inherent in the berry." The Penny Magazine for June 14, 1834, after deploring "the straw-colored fluid commonly introduced under the misnomer of coffee in England", thus digests Professor Donovan's findings:

Mr. Donovan found, that what we shall call the medicinal quality of coffee resides in it independent of its aromatic flavor,--that it is possible to obtain the exhilarating effect of the beverage without gratifying the palate,--and, on the other hand, that all the aromatic quality may be enjoyed without its producing any effect upon the animal economy. His object was to combine the two.

The roasting of coffee is requisite for the production of both these qualities; but, to secure them in their full degree, it is necessary to conduct the process with some skill. The first thing to be done is to expose the raw coffee to the heat of a gentle fire, in an open vessel, stirring it continually until it assumes a yellowish colour. It should then be roughly broken,--a thing very easily done,--so that each berry is divided into about four or five pieces, when it must be put into the roasting apparatus. This, as most commonly used, is made of sheet-iron, and is of a cylindrical shape: it no doubt answers the purpose well, and is by no means a costly machine, but coffee may be very well roasted in a common iron or earthenware pot, the main circumstances to be observed being the degree to which the process is carried, and the prevention of partial burning, by constant stirring. One of the requisites for having good coffee is that it shall have been recently roasted.

Coffee should be ground very fine for use, and only at the moment when it is wanted, or the aromatic flavour will in some measure be lost. To extract all its good qualities, the powder requires two separate and somewhat opposite modes of treatment, but which do not offer any difficulty when explained. On the one hand, the fine flavour would be lost by boiling, while, on the other, it is necessary to subject the coffee to that degree of heat in order to extract its medicinal quality. The mode of proceeding, which, after many experiments, Mr. Donovan found to be the most simple and efficacious for attaining both these ends, was the following:--

The whole water to be used must be divided into two equal parts. One half must be put first to the coffee "cold", and this must be placed over the fire until it "just comes to a boil", when it must be immediately removed. Allowing it then to subside for a few moments the liquid must be poured off as clear as it will run. The remaining half of the water, which during this time should have been on the fire, must then be added "at a boiling heat" to the grounds, and placed on the fire, where it must be kept "boiling" for about three minutes. This will extract the medicinal virtue, and if then the liquid be allowed again to subside, and the clear fluid be added to the first portion, the preparation will be found to combine all the good properties of the berry in as great perfection as they can be obtained. If any fining ingredient is used it should be mixed with the powder at the beginning of the process.

Several kinds of apparatus, some of them very ingenious in their construction, have been proposed for preparing coffee, but they are all made upon the principle of extracting only the aromatic flavour, while Professor Donovan's suggestions not only enable us to accomplish that desirable object, but superadd the less obvious but equally essential matter of extracting and making our own all the medicinal virtues.

When Webster and Parkes published their Encyclopedia of Domestic Economy, London, 1844, they gave the following as "the most usual method of making coffee in England":

Put fresh ground coffee into a coffee-pot, with a sufficient quantity of water, and set this on the fire till it boils for a minute or two; then remove it from the fire, pour out a cupful, which is to be returned into the coffee-pot to throw down the grounds that may be floating; repeat this, and let the coffee-pot stand near the fire, but not on too hot a place, until the grounds have subsided to the bottom; in a few minutes the coffee will be clear without any other preparation, and may be poured into cups; in this manner, with good materials in sufficient quantity, and proper care, excellent coffee may be made. The most valuable part of the coffee is soon extracted, and it is certain that long boiling dissipates the fine aroma and flavour. Some make it a rule not to suffer the coffee to boil, but only to bring it just to the boiling point; but it is said by Mr. Donovan that it requires boiling for a little time to extract the whole of the bitter, in which he conceives much of the exhilarating qualities of the coffee reside.

This work had also the following to say on the clearing of coffee, which was then a much-mooted question:

The clearing of coffee is a circumstance demanding particular attention. After the heaviest parts of the grounds have settled, there are still fine particles suspended for some time, and if the coffee be poured off before these have subsided, the liquor is deficient in that transparency which is one test of its perfection; for coffee not well cleared has always an unpleasant bitter taste. In general, the coffee becomes clear by simply remaining quiet for a few minutes, as we have stated; but those who are anxious to have it as clear as possible employ some artificial means of assisting the clearing. The addition of a little isinglass, hartshorn shavings, skins of eels or soles, white of eggs, egg shells, etc., has been recommended for clearing; but it is evident that these substances, to produce their effect, which is upon the same principle as the fining of beer or wine, should be dissolved previously, for if put in without, it would require so much time to dissolve, that the flavour of the coffee would vanish.

Coffee-making devices of this period in England, in addition to the Rumford type of percolator and the popular coffee biggin, included Evans' machine provided with a tin air-float to which was attached a filter bag containing the coffee; Jones' apparatus, a pumping percolator; Parker's steam-fountain coffee maker, which forced the hot water upward through the ground coffee; Platow's patent filter, previously mentioned, a single vacuum glass percolator in combination with an urn; Brain's vacuum or pneumatic filter employing a "muslin, linen or shamoy leather filter" and an exhausting pump, designed for kitchen use; and Palmer's and Beart's pneumatic filtering machines of similar construction.

Cold infusions were common, the practise being to let them stand overnight, to be filtered in the morning, and only heated, not boiled.

Coffee grinding for these various types of coffee makers was performed by iron mills; the portable box mill being most favored for family use. "It consisted of a square box either of mahogany or iron japanned, containing in the interior a hollow cone of steel with sharp grooves on the inside; into this fits a conical piece of hardened iron or steel having spiral grooves cut upon its surface and capable of being turned round by a handle." There was a drawer to receive the finely ground coffee. Larger wall-mills employed the same grinding mechanism.

In 1855, Dr. John Doran wrote in his "Table Traits":

With regard to the making of coffee, there is no doubt that the Turkish method of pounding the coffee in a mortar is infinitely superior to grinding it in a mill, as with us. But after either method the process recommended by M. Soyer may be advantageously adopted; namely, "Put two ounces of ground coffee into a stew-pan, which set upon the fire, stirring the coffee round with a spoon until quite hot, then pour over a pint of boiling water; cover over closely for five minutes, pass it through a cloth, warm again, and serve."