All About Coffee



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The French make an extremely strong coffee. For breakfast, they drink one-third of the infusion, and two-thirds of hot milk. The café noir used after dinner, is the very essence of the berry. Only a small cup is taken, sweetened with white sugar or sugar-candy, and sometimes a little eau de vie is poured over the sugar in a spoon held above the surface, and set on fire; or after it, a very small glass of liqueur, called a chasse-café, is immediately drunk. But the best method, prevalent in France, for making coffee (and the infusion may be strong or otherwise as taste may direct) is to take a large coffee-pot with an upper receptacle made to fit close into it, the bottom of which is perforated with small holes, containing in its interior two movable metal strainers, over the second of which the powder is to be placed, and immediately under the third. Upon this upper strainer pour boiling water, and continue to do so gently; until it bubbles up through the strainer: then shut the cover of the machine close down, place it near the fire, and so soon as the water has drained through the coffee, repeat the operation until the whole intended quantity be passed. No finings are required. Thus all the fragrance of its perfume will be retained with all the balsamic and stimulating powers of its essence. This is a true Parisian mode, and voila! a cup of excellent coffee.

This article is most interesting in that it shows the revolt against boiling coffee had started in the United States; also that the importance of fine grinding was being recognized and emphasized by the leaders of the best thought of the nation.

Probably the first scientific inquiry into the subject of coffee roasting and brewing in the United States was that detailed by August T. Dawson and Charles M. Wetherill, Ph.D., M.D., in the Journal of the Franklin Institute for July and August, 1855. The following is a digest:

There are two classes of beverages: 1, alcoholic, and 2, nitrogenized. Nitrogenized foods are effective to replace the substance of the different organs of the body wasted away by the process of vitality. Coffee is one of these.

Besides the tannin, the coffee berry contains two substances, one the nitrogenized quality, caffeine, which is about one percent and is not altered in roasting, and the other a volatile oil which is developed in roasting and which gives the coffee its flavor. Dr. Julius Lehmann (Liebig's Annales LXXXVII. 205) says that coffee retards the waste tissues of the body and diminishes the amount of food necessary to preserve life. This effect is due to the oil. Much of the nutritive portion of coffee is lost by European methods of making.

Good coffee is very rare. These experiments were made to ascertain whether a potable coffee could not be offered to the public at as low a price as the raw or roasted now is. In order to be successful we needed to extract a larger portion of the nutritive substance than is extracted in the household. The experiments have proved vain.

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.

In 1886, however, Jabez Burns, who knew something about the practical making of the beverage as well as the roasting and grinding operations, said:

Have boiling water handy. Take a clean dry pot and put in the ground coffee. Place on fire to warm pot and coffee. Pour on sufficient boiling water, not more than two-thirds full. As soon as the water boils add a little cold water and remove from fire. To extract the greatest virtue of coffee grind it fine and pour scalding water over it.

John Cotton Dana, of the Newark Public Library, says he remembers how in his old home in Woodstock, Vt., they had always, in the attic, a big stone jar of green coffee. This was sacred to the great feast days, Thanksgiving, Christmas, etc. Just before those anniversaries, the jar was brought forward and the proper amount of coffee was taken out and roasted in a flat sheet-iron pan on the top of the stove, being stirred constantly and watched with great care. "As my memory seems to say that this was not constantly done," says Mr. Dana, "it would seem that, even then, my father, who kept the general store in the village, bought roasted coffee in Boston or New York."

At the close of the century, there were still many advocates of boiling coffee; but although the coffee trade was not quite ready to declare its absolute independence in this direction, there were many leaders who boldly proclaimed their freedom from the old prejudice. Arthur Gray, in his Over the Black Coffee, as late as 1902, quoted "the largest coffee importing house in the United States" as advocating the use of eggs and egg-shells and boiling the mixture for ten minutes.

Latest Developments in Better Coffee Making



Better coffee making by co-operative trade effort got its initial stimulus at the 1912 convention of the National Coffee Roasters Association. As a result of discussions at that meeting and thereafter, a Better Coffee Making Committee was created for investigation and research.

The coffee trade's declaration of independence in the matter of boiled coffee was made at the 1913 convention of the National Coffee Roasters Association, when, after hearing the report of the Better Coffee Making Committee, presented by Edward Aborn of New York, it adopted a resolution saying that the recommendations met with its approval and ordering that they be printed and circulated.

The work done by the committee included "the first chemical analysis of brewed coffee on record", a study of grindings, and a comparison of the results of four brewing methods. Its conclusions and recommendations were embodied in a booklet published by the National Coffee Roasters Association, entitled From Tree to Cup with Coffee, and were as follows:

ROASTING

The Roaster or "Coffee Chef" is the only cook necessary to a good cup of coffee. He sends it to the consumer a completely cooked product.

In the roasting process the berries swell up by the liberation of gases within their substance. The aromatic oils contained in the cells are sufficiently developed or "cooked", and made ready for instantaneous solution with boiling water, when the cells are thoroughly opened by grinding.

The roasting principles of different green coffees vary. Trained study and a nice science in timing the roast and manipulating the fire is necessary to a perfect development of aroma and flavor.

The drinking quality is largely dependent upon the experienced knowledge of the coffee roaster and his scientific methods and modern machinery, by which the coffee is not only roasted, but cleaned, milled and completely manufactured to a high point of perfection.

In their National Association work, the wholesale roasters are giving the public new facts and valuable information, from scientific researches, investigations, etc.

GRINDING. The roasted berry is constructed of fibrous tissues formed into tiny cells visible only under the microscope, which are the "packages" wherein are stored the whole value of coffee, the aromatic oils. Like cutting open an orange, the grinding of coffee is the opening of surrounding tissue and pulp, and the finer it is cut the more easily are the "juices" released.

The fibrous tissue itself is waste material, yielding, by boiling or too long percolations, a coffee colored liquid which is fibrous and twangy in taste, has no aromatic character, and contains undesirable elements.

The true strength and flavor of roasted coffee is ground out, not boiled out. The finer coffee is ground, the more thoroughly are the cells opened, the surfaces multiplied, and the aromatic oils made ready for separation from their husks. Hence it follows that:

Coarse ground coffee is unopened coffee--coffee thrown away.

The finer the grind, the better and greater the yield. With pulverized coffee (fine as corn meal) the fully released aromatic oils are instantaneously soluble with boiling water.

In ground coffee the oils are standing in "open packages," escaping into the air and absorbing moisture, etc., necessitating quick use or confinement in air proof and moisture proof protection.

BREWING. From scientific researches by the National Coffee Roasters' Association, including the first chemical analysis on record of brewed coffee, produced by various brewing methods, the fundamental principles of coffee making have been clearly established. These principles are simple, and when once understood equip any person to intelligently judge the merits and defects of the various coffee making devices on the market. They constitute the law of coffee brewing, and may be stated as follows:

Correct brewing is not "cooking." It is a process of extraction of the already cooked aromatic oils from the surrounding fibrous tissue, which has no drinkable value. Boiling or stewing cooks in the fibre, which should be wholly discarded as dregs, and damages the flavor and purity of the liquid. Boiling coffee and water together is ruin and waste.

The aromatic oils, constituting the whole true flavor, are extracted instantly by boiling water when the cells are thoroughly opened by fine grinding. The undesirable elements, being less quickly soluble, are left in the grounds in a quick contact of water and coffee. The coarser the grind the less accessible are the oils to the water, thus the inability to get out the strength from coffee not finely enough ground.

Too long contact of water and coffee causes twang and bitterness, and the finer the grind the less the contact should be. The infusion, when brewed, is injured by being boiled or overheated. It is also damaged by being chilled, which breaks the fusion of oils and water. It should be served immediately, or kept hot, as in a double boiler.

Tests show that water under the boiling point, 212°, is inefficient for coffee brewing, and does not extract the aromatic oils[378]. Used under this temperature, it is a sure cause of weak and insipid flavor. The effort to make up this deficiency by longer contact of coffee and water, or repeated pouring through, results in no extraction of the oils, but draws out undesirable elements, such as coffee-tannin, which is soluble in water at any temperature and is governed by the time of contact.

Coffee-tannin, which is not the commercial tannic acid, is eliminated to practically nothing in the quick brewing methods.

The chemical analysis of brewed coffee shows the following:

Coffee Tannin Comparative per Cup Proportions

Percolator method,[379] fine gran. 2.90 grains -------- 5 minutes' steeping

Boiling Method, medium " 2.35 " ------

Steeping Method, " " 2.31 " -----

Filtration (or Drip) Method } 0.29 " - Pulverized }

Brewing is the final manufacturing process of coffee. All previous perfection is dependent upon it. Like food products which lose nutritive value by bad cooking, coffee loses its best values by wrong brewing. Brewed by the very simple correct methods, it is an unfailingly clear, fragrant, taste-charming beverage, universally loved and scientifically approved.

The committee made a further report in 1914, and some of the findings were subsequently published in an association booklet called The Coffee Book, used in connection with the second National Coffee Week campaign in 1915. In it were these:

GRINDING DEFINITIONS

Powdered Pulverized Like--flour. Like--not coarser than fine corn meal.



Very Fine and Fine MediumLike--from corn meal to Like--coarse granulated fine granulated sugar. sugar.

Also, the committee emphasized its previous findings, particularly this one: "Filter bags should be kept in cold water when not in use. Drying causes decomposition. Keeps sweet if kept wet. Use muslin for filter bag and pulverized granulation."

The association brought out this same year, on recommendation of the committee, its Home coffee mill, an "ideal and standard coffee mill for home use." It was a wall mill equipped with a glass-front metal hopper and employing a ratchet spring-lock nut and double-action grinders. The mill was later improved with an all-glass hopper and a tumbler bracket. More than 20,000 of these mills have been sold.

At the suggestion of the author, the efficiency of nine different coffee-making devices (including boiling and drip pots, pumping percolators, cloth and paper filters) was investigated in the laboratories of the Mellon Institute of Industrial Research of the University of Pittsburgh in 1915; and Dr. Raymond F. Bacon submitted a report that showed that the boiling method produced the highest percentage of caffetannic acid and caffein; the French drip process the lowest. The investigation disclosed also a more palatable brew at 195° to 200° F. than at the boiling point.

Another notable contribution to the science of coffee brewing was made by the Home Economics Laboratories of the University of Kansas in 1916. The experiments extended over one year. They showed that strength and color in coffee brews are independent of blend and price and are most fully obtained by pulverized granulation, which was found to be the most efficient; that the consumer pays for flavor and that filtration yielded the best brew. The French drip, or true percolator, did not figure in these experiments.

At the 1915 convention of the National Coffee Roasters Association, Mr. Aborn reported that 4,000 copies of the committee's findings on grinding and brewing had been given away: and the facts were further circulated in 2,000,000 booklets issued during two years. He told of tests which showed that while there might be reasons of commercial expediency for packing ground coffee, it could not be defended as a quality principle; also that plate-grinders produced a more efficient drawing granulation than roller grinders, and that the idea that the steel-cut process eliminates dirt was an absurdity, as "the finest ground coffee is not dirt but coffee in its most efficient drawing condition." He added, "I have paid no attention to chaff removal in these tests as the uselessness of such removal has been repeatedly shown up." The reference here was to his 1914 and 1913 reports, in which it was stated that "removing the chaff in the steel-cut process does not remove any of the tannin, and for this purpose the steel-cut process is wholely futile, and a wasteful and unnecessary tax upon cost", and that "the removal of the chaff appreciably affects the flavor and depreciates the cup value."

This report repeated previous findings against the pumping percolator as producing an inefficient brew and being a very faulty utensil. Mr. Aborn concluded his report by saying:

The old time boiling method has fewer and fewer defenders and holds its own only as a superstition. I therefore pass it over as a discarded issue.... It is but repetition of former reports for me to say that pulverized granulation is the most efficient granulation; that it assures the highest quality of brew and the lowest proportion of coffee to a given strength; that it is the most saving and most satisfying grinding for all to use; that it (the coffee) must be fresh ground; that the filtration method is the most correct in fundamental principles and that used with a muslin bag it assures the consumer coffee of the purest, finest flavored quality, highest health value and sure economy.

The campaign of education was continued during 1916, producing encouraging results among schools, colleges, the medical fraternity, newspapers, with the trade and the consumer. It marked the first big constructive work combining the practical and scientific phases of grinding and brewing methods. In his report at the 1916 convention of the National Coffee Roasters Association, Mr. Aborn reviewed the four years work, and pointed out what had been accomplished. He told of a new booklet, to be called the True Book on Coffee Grinding and Brewing, and an educational exhibit box for schools about to be issued. Due to opposition which developed from trade interests that were putting out steel-cut and other grinds of coffee not favored by the committee, and also because many members thought the association should not exploit any particular method of grinding or brewing, it was decided to make no further publication of the coffee grinding and brewing conclusions of the committee until they had been confirmed by laboratory research.

Boiling and filtration tests in the mountains of the Yellowstone Park by W.H. Aborn in 1916 showed that the limit of coffee brewing was reached at an altitude of nine thousand feet.

At the 1916 meeting, Dr. Floyd W. Robison of the Detroit Testing Laboratories, read a notable paper entitled "What do we know about coffee?," which hailed coffee as a food product, warned the roasters to beware of half-facts, and urged the importance of a research laboratory. It was published and given distribution by the association.

The educational exhibit box showing samples of coffee from plantation to cup, including five different grinds, was issued in 1917, and sold for one dollar.

The Better Coffee Making Committee also published in this year a booklet entitled Coffee Grinding and Brewing in which it summarized its work to date, and presented its special plea for cotton-cloth filters as the ideal coffee-making device.

This booklet aroused considerable discussion, particularly between those who favored the paper filter and those who, with Mr. Aborn, believed cotton cloth, such as muslin, to be the most efficient strainer. "Cotton", argued Mr. Aborn, "is an ideal sanitary strainer because it contains no chemical or questionable manufacturing element."

It was pointed out by Dr. Floyd W. Robison that while cotton cloth, such as muslin, does give a fairly clear coffee, it is not so clear as by the methods where a filter paper is used. He said:

Both methods have serious objectionable features. The muslin bag, particularly, is decidedly unsanitary, especially when used in restaurants and hotels. It is rarely kept clean, and one who has frequented restaurants and many hotel kitchens knows that it lends itself to very unclean and unsightly methods of handling. The food inspector has to check this up perhaps as often as any one feature about a restaurant.

The objection to the filter paper is not at all on the ground of sanitation. It is ideal in this respect. The claim is made, and at least, in part, substantiated, that it does hold back valuable features of the brew.

There are many points about the filter that have not been considered at all. Mr. Calkin believes that the very best type of filter is a bed of coffee itself, and I must say this has the sanction of good laboratory experience.

I.D. Richheimer[380], attacking the cotton cloth filter, said:

It is a known fact that the fats in coffee are very dense and represent twelve to fifteen percent of the coffee weight. These fats--due to the simplest chemical action of contact with air, moisture and continued heat--begin a fermentation in the completed beverage. In the cloth-filtering process--due to the rapid passage of water through grounds almost as quickly as poured--the largest percentage of fats is carried into the beverage. Fat being lighter than water rises to the top of water if given a certain amount of time during the brewing process. Were there no fats (which ferment) in coffee there would be no need for placing cloth-filtering material under water, as suggested, to keep them from becoming sour.

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