COFFEE GRINDING
_“Steel-cut” coffee—Wholesale coffee grinding—Evolution of grinding
apparatus._
Unless the coffee is to be sold in the bean, it is sent to the grinding
and packing department, to be further prepared for the consumer.
Since the federal Food Law has been in effect, the public has gained
confidence in ground and bean coffee in packages; and today a large
part of the coffee consumed in the United States is sold in one- and
two-pound cartons and cans, already blended and ready for brewing.
_“Steel-Cut” Coffee_
A progressive coffee-packing house may have three different styles
of grinding machines; one called the granulator for turning out the
so-called “steel-cut” coffee; the second, a pulverizer for making a
really fine grind; and the third, a grinding mill for general factory
work and producing a medium-ground coffee.
Commercial coffee-grinding machines are alike in principle in all
countries, the beans being crushed or broken between toothed or
corrugated metal or stone members, one revolving and the other being
stationary. While all grinding machines are alike in principle, they
may vary in capacity and design. The average granulator will turn out
about 500 pounds of “steel-cut” coffee in an hour; the pulverizer, 75
to 100 pounds; and the average grinding mill, 500 to 600 pounds. Some
types of grinding machines have chaff-removing attachments to extract,
by air suction, the chaff from the coffee as it is being ground.
A large number of trade terms for designating different grinds of
coffee are used in the United States, some of them meaning the same
thing, while similar names are sometimes contradictory. A canvass of
the leading American coffee packers in 1917 discovered that there
were 15 terms in use, and that there were 34 different meanings
attached to them. For the term “fine,” there were five different
definitions; “medium” had five; “coarse,” seven; “pulverized,” four;
“steel-cut,” seven; “ground,” two; “powdered,” one; “percolator,”
two; “steel-cut-chaff-removed,” one; “Turkish ground,” one; while
“granulated,” “Greek ground,” “extra fine,” “standard,” and “regular”
were not defined.
The term “steel-cut” is generally understood to mean that in the
grinding process the chaff has been removed and an approximate
uniformity of granules has been obtained by sifting. The term does not
necessarily mean that the grinding mills have steel burrs. In fact,
most firms employ burrs made of case iron or of a composition metal
known as “burr metal,” because of its combined hardness and toughness.
The “steel-cut” idea is another of those sophistries for which American
advertising methods have been largely responsible in the development of
the package-coffee business in the United States. The term “steel-cut”
lost all its value as an advertising catchword for the original user
when every other dealer began to use it, no matter how the ground
coffee was produced. When the public has been taught that coffee should
be “steel-cut,” it is hard to sell it ground coffee unless it is called
“steel-cut”; although a truer instructor of the consumer would have
caused him to insist on buying whole bean coffee to be ground at home.
“Steel-cut” coffee—that is, a medium-ground coffee with the chaff
blown out—does not compare in cup test with coffee that has been more
scientifically ground and not given the chaff-removal treatment that is
largely associated in the public mind with the idea of the “steel-cut”
process.
According to the results of the trade canvass previously referred to,
it would appear that the terms most suited to convey the right idea
of the different grades of grinding, and likely to be acceptable to
the greatest number, would be “coarse” (for boiling and including all
the coarser grades); “medium” (for coffee made in the ordinary pot,
including the so-called “steel-cut”); “fine” (like granulated sugar,
and used for percolators); “very fine” (like cornmeal, and used for
drip or filtration methods); “powdered” (like flour, and used for
Turkish coffee).
Coffee begins to lose its strength immediately after roasting, the rate
of loss increasing rapidly after grinding. In a test carried out by
a Michigan coffee packer, it was discovered that a mixture of a very
fine with a coarse grind gave the best results in the cup. It was also
determined that coarse-ground coffee lost its strength more rapidly
than the medium ground; while the latter deteriorated more quickly than
a fine ground; and so on, down the scale. His conclusions were that the
most satisfactory grind for putting into packages that were likely to
stand for some time before being consumed was a mixture consisting of
about 90 percent finely ground coffee and 10 percent coarse. His theory
is that the fine grind supplies sufficiently high body extraction; the
coarse, the needful flavor and aroma. On this irregular grind a United
States patent (No. 14,520) has been granted, in which the inventor
claims that the 90 percent of fine eliminates the interstices—that
allow too free ventilation in a coarse-ground coffee—and consequently
prevents the loss of the highly volatile constituents of the 10 percent
of coarse-ground particles, and at the same time gives a full-body
extraction.
_Wholesale Coffee Grinding_
As long as there continues a consumer demand for ground package coffee,
there will be found manufacturers willing to supply it, despite all the
well-turned arguments in favor of grinding at home or in the shop at
the time of purchase.
There are to be had factory mills in which coffee may be reduced to the
desired fineness at one passage through a pair of metal-disk grinding
plates, which are capable of producing 500 pounds an hour of finely
ground coffee such as will pass completely through a square-mesh sieve
having ³/₆₄-inch clear openings. These mills can be made to produce as
much as 1,000 to 1,500 pounds of finely ground coffee an hour.
For retail distributers there are many excellent counter mills that
render efficient service in grinding whole-bean loose or package coffee
for the housewife while she waits.
_Evolution of Grinding Apparatus_
In the beginning,—that is to say, in Ethiopia, about 800 A. D.,—a
primitive stone mortar and pestle were the original coffee grinder.
Next, the coffee beans were ground between little millstones, one
turning above the other; then came the mill used by the Greeks and
Romans for grain. This mill consisted of two conical millstones, one
hollow and fitted over the other, specimens of which have been found in
Pompeii. The idea is the same as that employed in the most modern metal
grinder.
In the 15th century, we notice the first appearance of the familiar
Turkish pocket-cylinder coffee mill. The Turkish coffee grinder seems
to have suggested the individual-cylinder roaster which later (1650)
became common, and from which developed the huge, modern, cylinder
commercial roasting machines.
Between 1428 and 1448, a spice grinder standing on four legs was
invented, and this was later used for grinding coffee. The drawer to
receive the ground coffee was added in the 18th century.
Between 1600 and 1632, mortars and pestles of wood, iron, brass, and
bronze came into common use in Europe for braying the roasted beans.
For several centuries, coffee connoisseurs held that pounding the beans
in a mortar was superior to grinding in the most efficient mill.
Peregrine White’s parents brought to America on the Mayflower, in 1620,
a wooden mortar and pestle that were used for braying coffee to make
coffee “powder.”
The improved Turkish combination coffee grinder with folding handle and
cup receptacle for the beans, used for grinding, boiling, and drinking,
was first made in Damascus in 1665.
In 1665, Nicholas Book, “living at the Sign of the Frying Pan in St.
Tulies Street,” London, advertised that he was “the only known man for
making of mills for grinding of coffee powder, which mills are sold by
him from 40 to 45 shillings the mill.”
Coffee grinders were so common in France in 1720 that they were to be
had for $1.25 each. Their development by the French had been rapid
from the original spice grinder. At first, they were known as coffee
mills; but in the 18th century, roasters came to be known by that
name. They were made of iron, retaining the same principle of the
horizontal millstones—one of which is fixed while the other moves—that
the ancients employed for grinding wheat. They were squat, box-shaped
affairs, having in the center a shank of iron that revolved upon a
fixed, corrugated iron plate. There was also the style that fastened to
the wall. At first, the drawer to receive ground coffee was missing,
but this was supplied in later types. Before its invention, the ground
coffee was received in a sack of greased leather, or in one treated on
the outside with beeswax—probably the original of the duplex paper bag
for conserving the flavor.
The French brought their innate artistic talents to bear upon coffee
grinders, just as they did upon roasters and serving pots. In many
instances, they made the outer parts of silver and of gold.
English and American inventors soon afterward produced the well-known
wall-mill type of coffee grinder. The original Parker mill appeared in
1832. Jabez Burns secured a patent on his granulating mill in 1872.
Mr. Burns had some very definite ideas on the subject of grinding
coffee, as well as on how the product should be roasted. At that time
the French and English lap and wall mills, the English steel mills, and
the Swift mills were all used in the United States. Troemner’s, the
Enterprise, and others were extending their use in a retail way; but
Jabez Burns confined his attention to a practicable mill for wholesale
grinding establishments.
For manufacturing purposes, burr-stone mills were for many years
exclusively employed, especially one first known as the Prentiss &
Page, and later as the Page mill. There was a time when all coffee
establishments in New York sent their coffee to Prentiss & Page to be
ground. Some of the places roasted by hand, others by horse power; and,
if by steam, it was limited, and they did not have enough to spare for
grinding.
With the march of improvement, burr-stone mills went into the discard.
The difficulty lay in finding men experienced in stone dressing to run
them; and the demand grew for a better style of grinding than could
be done in a mill out of face and balance. This demand was met in an
altogether different style of machine, which for 25 years was well
known as the Barbor mill. It was for improvements on this mill that
Jabez Burns in 1867, 1872, and 1874 obtained his granulator patents.
The mill comprised cutters in the form of an iron roller running in
near contact with a concave, also of iron, and a revolving cylinder
provided with sieves, or screens, that received the ground material,
rolled it over the wire surface, sifting out the fine and discharging
the course automatically into the cutter, to be again manipulated until
it was fine enough to pass through the meshes of the screen.
In 1875-76-78, Turner Strowbridge, of New Brighton, Pennsylvania, was
granted three United States patents on a box coffee mill.
In 1878, Landers, Frary & Clark, New Britain, Connecticut, brought out
an improved box coffee grinder for home use.
In 1878 and 1880, United States patents were issued to John C. Dell, of
Philadelphia, on a store coffee mill.
In 1879 and 1880, United States patents were issued to Orson W. Stowe,
of the Peck, Stowe & Wilcox Company, Southington, Connecticut, on a
household coffee mill.
In 1881, the Morgan Brothers, Edgar H. and Charles, began the
manufacture of household coffee mills, the business being acquired in
1885 by the Arcade Manufacturing Company, of Freeport, Illinois. The
latter concern brought out the first pound coffee mill in 1889. Its
mills became very popular in the United States. In 1900, Charles Morgan
was granted a United States patent on a glass-jar coffee mill, with
removable glass measuring cup.
In 1897, the Enterprise Manufacturing Company, of Pennsylvania, was the
first regularly to employ electric motors for driving commercial coffee
mills by means of belt-and-pulley attachments.
In 1898, the Hobart Manufacturing Company, of Troy, Ohio, introduced to
the trade another early coffee grinder connected with an electric motor
and driven by belt-and-pulley attachment.
In 1900, the first gear-driven electric coffee grinder was put on the
market by the Enterprise Manufacturing Company, of Pennsylvania.
In 1902, the Coles Manufacturing Company (Braun Company, successor)
and Henry Troemner, of Philadelphia, began the manufacture and sale of
gear-driven electric coffee grinders.
In 1905, the A. J. Deer Company, Buffalo, New York (now at Hornell, New
York), began to sell its Royal electric coffee mills direct to dealers
on the installment plan, revolutionizing the former practice of selling
coffee mills through hardware jobbers.
In 1905, H. L. Johnston was granted a United States patent on a coffee
mill. He assigned the patent to the Hobart Manufacturing Company.
In 1905, a celebrated case was decided in Kansas City involving
litigation between William E. Baker, of Baker & Company, Minneapolis,
and the F. A. Duncombe Manufacturing Company, of St. Joseph, Missouri,
over Mr. Baker’s patent rights in a machine to produce steel-cut
coffee. The suit was brought in 1903, and Mr. Baker contended that his
patent gave him the exclusive right to the “uniformity of granules
by means of the sharply dressed mechanism” and by the use of a fan
for blowing away the silver skins, produced by his machine; while
the defendant said he obtained the same result (steel-cut coffee) by
grading the granules through screens or sieves. The defense was that
Mr. Baker’s process was not a discovery; because, grinding coffee was
as old as the world’s knowledge, and winnowing the chaff was equally
ancient. The lower court dismissed the bill, because the “patents sued
upon are devoid of patentable invention,” and the United States Court
of Appeals confirmed the decision.
Herbert L. Johnston, assignor to the Hobart Electric Manufacturing
Company, Troy, Ohio, was granted a United States patent on a machine
for refining coffee in 1913.
In 1915, the National Coffee Roasters Association’s Home coffee
mill, employing an improved set screw operating on a cog-and-ratchet
principle, was introduced to the trade.
In 1916, Jules Le Page, Darlington, Indiana, obtained two United States
patents on cutting rolls to cut—and not to grind or crush—corn, wheat,
or coffee. These were subsequently incorporated in the Ideal steel-cut
coffee mill and marketed to the trade first by the B. F. Gump Company,
Chicago, and later through Jabez Burns & Sons, New York.
[Illustration: SOME OF THE LEADING TRADE-MARKED COFFEE CONTAINERS
1. Double carton. 2-3. Cartons. 4. Fiber sides, tin top and
bottom, friction cover. 5. Vacuum tin can. 6. Fancy paper bag. 7.
Machine-wrapped paper package. 8. Fancy paper bag. 9. Carton with
patented opening and closing device. 10. Wrapped paper package. 11. Tin
can with slip cover. 12. All-fiber can with slip cover. 13. Tin can
with slip cover. 14. Lithographed tin can with friction cover. 15-16.
Tin cans with slip covers. 17. Squat tin cans. 18. Napacan. 19-20-21.
Vacuum tin cans.]