The Science of Coffee Brewing: History, Myths & Perfecting the Cup (1922)

📌 Step back to 1922 and uncover the art and science of coffee brewing! ☕ Learn why boiled coffee is spoiled coffee, how grind size affects flavor, and why the drip method reigns supreme. A must-read for coffee lovers, foodies, historians, baristas, teachers, and students! 🔥📖

Poster on How to Make Coffee. Tea and Coffee Trade Journal, April 1922. GGA Image ID # 222a643490. Click to View a Larger Image.

☕ The Art & Science of Coffee Brewing (1922)

🔎 An Epicurean’s Guide to Coffee: From History to the Perfect Cup

Edward Aborn’s 1922 article, How to Make Coffee, originally published in the Tea and Coffee Trade Journal, is a treasure trove for epicureans, food historians, baristas, teachers, students, and coffee lovers alike. Aborn, a former Vice President of the National Coffee Roasters Association, combines history, science, and practical brewing techniques, offering a compelling narrative on how coffee became an essential part of daily life while also correcting common brewing mistakes that ruin its flavor.

For foodies and coffee connoisseurs, this article is a fascinating glimpse into how brewing techniques have evolved and how, even a century ago, experts were advocating for precision in coffee making—a topic that remains just as relevant today.

I am going to speak to you about a beverage that has rightly been called the "universal drink." Its use is as wide as civilization itself. In the United States, we consume 40,000,000,000 cups of it every year. Every day of the year, it appears on the dining tables in 95 out of 100 American homes. My subject is Coffee.

Its history goes back at least 1,000 years. In 900, we find a "Wise Man of the East," an Arab physician bearing the gift of coffee. The charmed East, that treasure land, with a wealth of products and a greater wealth of human experience, with prophets and seers whose teachings we live by, the cradle land of humanity, was the birthplace of coffee drinking.

As early as 1600, coffee became a sensation in England and France, where it was daily enjoyed by the leading geniuses of the day, great artists, writers, sculptors, and statesmen. The coffee house was literally a Hall of Fame, with coffee as inspiration. Indeed, coffee has always been associated in history with brains and talent.

There is also an interesting historical association of coffee with the growth of political independence. Its use was contemporaneous with the establishment of the English Commonwealth. The Sons of Liberty signed an important document, the American Declaration of Independence forerunner, in the Merchants' Coffee House. over the coffee cups at Wall and Water Sts., New York, on May 23, 1774.

A New York market report in 1829 reads, "The import of coffee this week was two tierces, 1 barrel, 715 bags," less than 100,000 pounds. The average weekly import into the United States during 1921 was 25,500,000 pounds. Our annual per capita consumption increased from three pounds in 1830 to 12% in 1921.

Coffee in Nature

Could vision be broadcasted like sound, I would show you a gracious sight coffee tree in blossom and fruitage, about as high as your porch roof, with laurel-like leaves, one of a family of shrubs and flowers, a relative of the gardenia, covered with a flurry of fragrant snow-white blossoms, and bearing at the same time cherries with bright red coats as though to attract that human "eye which seeth every precious thing."

In Brazil, which produces 70% of the world's coffee, the cherries are being picked. When the various coverings are removed, two little green berries are found in those cherries or pods, like pearls in a jewel case. Sometimes, there is but one, which curls itself into a round shape called a peaherry. The immaculately clean green coffee is sent worldwide after being undressed of its growing clothes and adequately washed and dried.

Observe the cunning providence of Nature! The coffee berry is ripened like fruit on a tropical tree. And yet, unlike fruit, it is not in perishable condition. Improving by age in the green state seems destined for transportation to the peoples of the earth, in good condition for final development at its point of consumption.

Should Be Cooked Only Once

The green berry must now go to the cook, the roaster. After more cleaning by milling machines, it is sent running into a revolving, perforated oven called a roasting cylinder. Peeping in, you can see it excitedly tumbling about at a high temperature over a roaring red fire. It is slowly turning brown, swelling, and popping as the wonderful aromatic element is developed.

It is receiving the only cooking necessary for coffee in any state. It is "done to a turn" here, light, medium, or dark, as desired, corresponding with "rare, medium, well done." The strength of flavor, from mild to a burned taste, and the corresponding color of the brew are determined finally in this roasting process. The brown, crisp, roasted berry should not be considered raw material. To prove how thoroughly perfected its aromatic quality is, note the delightful fragrance when the coffee is being ground.

Observe again Nature's infinite wisdom. The roasted berry, all cooked, though now perishable and requiring reasonably quick use and protection against air and moisture, is still an unopened container, a fiber construction of tiny cells, each containing its treasure of aromatic substance, the whole value of coffee.

The fiber structure itself has no drinkable value. After extracting the aromatic oils, they should be discarded like an empty carton. It should never be cooked in with the brew.

Spoiled in the Home

But a sad fate too often awaits the great product, so carefully produced and protected to this point, in the home coffee pot. The coffee trade has realized for years that the quality of coffee served in the home cup is far from equal to that sold in the bean. Many times, it finds the choicest brands unrecognizable in liquid form.

When Mutt was asked in Jeff's restaurant whether he wanted to order coffee or tea, he said, "Give me one of them but don't tell me which. I want the fun of guessing what it is like I did the soup."

Scientific trade research has just answered the question: Why should coffee quality be so frequently ruined in the pot, and how can this be changed so that it can be enjoyed at its very best?

Official reports by coffee experts, chemists, and trained investigators have established a simple set of principles that should be known and practiced in every home.

They are briefly as follows:

How to Make the Beverage

After the grinder opens the roasted berry, the volatile aromatic element begins to escape, and the released oils, subject to the air, seriously change. The nearer the grinding is to the brewing, the better. When ground coffee is kept, airtight, moisture-proof containers should be used.

The finer the grind, the quicker, the better, and the more complete the extraction by the water. Every particle, as it is broken open, exposes additional surfaces.

The minute cells, visible only under the microscope, yield more and more as they are broken open by finer and finer grinding. Anyone may make this comparative absorption test:

Put a rounded tablespoonful of medium-ground coffee into one cup and a similar quantity of the same coffee, pulverized, into another. Pour an equal quantity of boiling water into each.

You will immediately notice that the pulverized produces about double the color and strength, with a truer, fuller flavor. This proves that the finer the grind, the quicker, the better, and the more complete the extraction.

Do not boil or stew the coffee grounds and water together. Prolonged or repeated contact of the water and the grounds dispels aroma, develops bitter and astringent elements, and seriously changes and impairs the quality and character of the brew.

“Boiled Coffee Is Spoiled Coffee”

A recent official report by the Massachusetts Institute of Technology confirms previous trade reports on the serious inferiority of spoiled boiled coffee.

Roasted coffee is already cooked and requires no further cooking. Correct, non-cooking infusion with water obtains the full value from the grounds, which then become dregs, not to be extracted or used again.

The United States Army, after several years of official testing of the advice of the National Coffee Roasters Association against boiled coffee, has completely changed the official army rule of 40 years standing, adopting the association recipe, eliminating the boiling principle, and greatly improving the soldiers' coffee.

Boiling coffee is a tradition. It dates back to barbarous times 900 years before roasting was discovered when the whole green berry was boiled.

Afterward, the whole roasted berry was boiled, as were the coarse pieces produced later by pounding in a mortar. Notwithstanding the advent of grinding machinery and the scientific proof of better methods, boiling coffee is still a vicious habit in this country, depriving thousands of its full enjoyment.

The water must be started at the boiling point. When the kettle is removed from the fire, with the water galloping, the temperature inevitably lowers somewhat.

By the time it penetrates the grounds, it is at the correct temperature, provided the operation is not over a hot fire, whereby a cooking process begins. Water started under the boiling point, reaching the grounds at an inefficiently low temperature, is a sure cause of a weak, defective brew. Boil the water. Don't boil the water and grounds together, and don't boil the brewed liquid.

Neither Cook nor Cool It

Neither cook nor cool the finished brew. Always serve it smoking hot. Serve it immediately after it is brewed, or, if unavoidably delayed, keep it over indirect heat where it will remain hot without cooking. Always use heated vessels. A chilled brew cannot be successfully reheated.

Strain correctly. So-called muddy or cloudy coffee is never due to the quality or character of the coffee itself but solely to faulty straining or settling. Among the crude “old settlers” are salt codfish skin, isinglass, eggshells, etc., operating only to weigh and sink the grounds, which should be filtered or strained out completely, making a radiantly clear coffee always sure.

Wire and perforated metal strainers do not hold the finest particles, lack a free filtering surface, and are difficult to keep clean and uncontaminated. Perforated glazed porcelain strainers have the finest particles and are of insufficient outlet. A paper filter is used, and a solid waste strainer requires support.

Cotton cloth of fine mesh holds the finest particles, has a free filtering surface, and can be frequently changed. However, it requires care in being kept sweet after use.

After being used, a filter or drip bag of cotton should be rinsed in cold water, not hot water, and then kept submerged in cold water, as in a covered glass tumbler, until next used. The water seals it from the spores in the air, which cause souring. Never dry it. Filter cloths or bags keep sweet if kept wet.

Undesirable Utensils

Use the correct utensils. Clean thoroughly and watch every crevice, corner, tube, sieve hole, and spout. Metal has long been discredited for tea and has the same disadvantage for coffee.

The Massachusetts Institute of Technology reports:

Metallic substances -yield pronounced flavors when cooked with an organic solution such as coffee infusion. We show in the laboratory that even a short contact of coffee infusion with metals is accompanied by a formation on the metal of a thin deposit which, we believe, is a chemical combination.”

The commonly used metal percolator, where the liquid is pumped up and sprayed over the grounds, has these faults: Metal strainer will not hold pulverized particles; water reaches grounds at insufficient temperature, as low as 140 to 150 degrees; sputtering, but not near enough to boiling to extract the aromatic substances fully; repeated contact of liquid and grounds, which dispels fragrance and extracts undesirable dreg elements.

When using a percolator, allow a brief time of percolating. Obtain the desired strength using the finest grind practicable for the sieve and an ample allowance of coffee. Measure water and coffee in all methods.

The Drip Method

Drip-method pots are obtainable in many forms. The drip or filtration method is generally accepted and approved by coffee authorities. Technology Research prefers it and says, "The filtration (drip) processes yield a clear, good coffee, with the right conditions of time, temperature, and utensil."

Here is a correct recipe for the filtration or drip method with a close-mesh cotton cloth as a filter, like the hotel and restaurant custom of using a suspended cloth filter bag:

The filter bag should be of such dimension as to permit a thorough but not delayed flow of water through the coffee. Put a measured quantity of coffee into the filter.

The strength of the brew must govern the quantity desired and the fineness of the grind used. For best results, use a very fine grind, not coarser than fine cornmeal or finer than powdered sugar (not powdered like flour).

Start with water at the boiling point and pour a measured quantity once through the grounds, dripping it into a previously heated earthenware vessel. Serve at once, and don't chill or cook the brew.

Serve it daintily, as it befits a perfect product. To prove that one pouring through obtains the full strength from very finely ground coffee, pass more water through the used grounds and see how this last extraction shows that it is only sanitary and easily cleaned but does not hold faint color and dreg flavor.

A brew made by this recipe may be strong and dark-colored, yet free from bitterness or astringency, with the native aroma of the kind of coffee strikingly evident.

The Massachusetts Institute of Technology, summarizing all recorded scientific reports, states that the stimulating element in coffee, caffeine, has been proven an uplifting stimulant with no after-depression.

Used in moderation, coffee is a great human resource. It deserves your intelligent interest and understanding of modern information about better brewing, which will multiply.

Edward Aborn, "How to Make Coffee," in Tea and Coffee Trade Journal, July 1922, p. 48-50.

☕ Key Takeaways: What Makes This Article Engaging?

📜 The Rich History of Coffee: A Universal Drink

🔹 "Coffee has always been associated in history with brains and talent."

🔹 Coffeehouses were the epicenters of intellectual and political movements, from 18th-century Europe to the American Revolution (where The Sons of Liberty plotted in New York’s Merchant’s Coffee House).

🔹 The U.S. per capita coffee consumption surged from 3 pounds in 1830 to 12.5 pounds in 1921, reflecting America’s obsession with the beverage.

💡 Why It’s Interesting:

✅ Food historians and culinary students can explore how coffee’s history intertwines with politics, culture, and social movements.

✅ Teachers can use this historical account to illustrate the global impact of trade and migration.

✅ Epicureans will appreciate how coffee became a staple of sophistication and intellectualism.

🌱 Coffee as a Botanical Wonder: Nature’s Gift

🔹 Aborn poetically describes coffee trees, calling them “a gracious sight” with snow-white blossoms and cherries resembling jewels.

🔹 Brazil was the world’s dominant producer, providing 70% of the world’s supply.

🔹 Coffee’s non-perishable nature allows it to be shipped worldwide, improving with age like fine wine before roasting.

💡 Why It’s Interesting:

✅ Foodies and coffee aficionados will love this romanticized look at coffee’s journey from plant to cup.

✅ Agriculture and botany students can examine coffee’s growth cycle, global trade, and economic impact.

🔥 The Science of Roasting: The True "Cooking" of Coffee

🔹 Roasting is the only cooking coffee ever needs—after that, it should not be boiled.

🔹 The "popping" and swelling of coffee beans under heat is essential for flavor development.

🔹 Roasting determines flavor strength (light, medium, or dark), much like a steak’s doneness.

🔹 A properly roasted coffee releases its natural aroma when ground—but once ground, flavor deterioration begins quickly.

💡 Why It’s Interesting:

✅ Baristas and home brewers can fine-tune their roasting and grinding habits for better flavor retention.

✅ Teachers and students of food science will find the chemical transformations in roasting fascinating.

🚫 The Biggest Brewing Mistakes & How to Avoid Them

1️⃣ The Myth of Boiling Coffee

🔹 "Boiled coffee is spoiled coffee."

🔹 Boiling destroys aromatic oils, leaving bitter and astringent flavors.

🔹 This outdated method originated from medieval times, before roasting was invented.

💡 Why It’s Interesting:

✅ Home brewers and coffee shops can improve their coffee quality by eliminating over-extraction mistakes.

2️⃣ Grind Size Matters: A Key to Extraction

🔹 The finer the grind, the quicker and more complete the extraction.

🔹 A side-by-side test: Coarse vs. finely ground coffee—the finer grind doubles the strength and flavor.

🔹 Poor brewing leads to weak or overly bitter coffee.

💡 Why It’s Interesting:

✅ Baristas, home brewers, and culinary students can experiment with grind size to optimize their brews.

3️⃣ Percolators: A Flawed Invention?

🔹 Percolators over-extract coffee, repeatedly cycling liquid through the grounds, resulting in bitterness.

🔹 Massachusetts Institute of Technology (MIT) reported that metal percolators chemically alter coffee flavors.

💡 Why It’s Interesting:

✅ Epicureans and coffee purists can ditch percolators in favor of better brewing techniques.

✅ Tech-minded students will appreciate the scientific validation of better brewing methods.

✨ The Perfect Brew: Drip Method

🔹 Aborn strongly recommends the drip method with fine cotton filters.

🔹 Instructions:

✅ Start with boiling water.

✅ Pour once through the grounds—never reuse them.

✅ Use a very fine grind (like cornmeal or powdered sugar).

✅ Serve immediately—never reheat or let it cool.

✅ For Epicureans, coffee lovers, and culinary students, this early endorsement of the drip method provides an essential look into timeless brewing principles.

🖼️ Noteworthy Images & Why They Matter

📌 Poster on How to Make Coffee (1922) – A visually engaging vintage guide, perfect for coffee historians, foodies, and collectors.

📌 Coffee Roasting Cylinder – Captures the transformative moment when coffee releases its aromatic oils, showing the science behind flavor development.

📌 Drip Coffee Setup – Showcases early 20th-century brewing techniques, still relevant in today’s specialty coffee culture.

🎯 Final Thoughts: Why This Article Matters Today

Edward Aborn’s 1922 guide to coffee brewing is shockingly ahead of its time, advocating modern techniques still used by today’s coffee connoisseurs and specialty brewers.

✅ For foodies & coffee lovers – It offers expert insights on maximizing flavor.

✅ For teachers & students – It provides a historical perspective on coffee culture, trade, and science.

✅ For baristas & home brewers – It is an essential guide to brewing better coffee.

✅ For historians – It links coffee culture to politics, economy, and social change.

💡 Whether you’re a seasoned coffee expert or just someone who enjoys a perfect cup in the morning, this 100-year-old wisdom remains as valuable as ever. ☕✨