Home Coffee Roasting

• Chapter 1 – Why Home Roasting?
• Chapter 2 – Brief Roasting History
• Chapter 3 – Roasting Styles
• Chapter 4 – Choosing Green Beans
• Chapter 5 – Methods & Equipment

Guide to Home Roasting Procedure

Home Coffee Roasting is excerpted from Kenneth Davids’ book titled Home Coffee Roasting: Romance and Revival, published by St. Martin’s Press, New York. Ken’s book is both a complete, authoritative guide to home roasting as well as a lively introduction to coffee roasting in general. This material is a small sampling of the book.

Chapter 1 – Why Home Roasting?
A few minutes ago I roasted several days’ supply of coffee in a stove-top popcorn popper. The whole process took about ten minutes. The popper can be purchased for about twenty to twenty-five dollars. The retail price of the coffee I roasted (a fancy Sumatra) might cost anywhere from five to six dollars a pound green. The same coffee purchased roasted at the corner coffee store would cost eight to ten dollars a pound. The coffee I produced was fresher than almost any I could have bought, and its freshness by far compensated for any small failings in roasting procedure. Green coffee beans keep well without special handling, so the modest effort required to acquire them doesn’t need to be undertaken often.

Nor was the stove-top popper my only option. I could have chosen to roast the coffee in a gas oven, for example, or in one of a certain design of hot-air corn popper, or in a device specially designed for home roasting.

Given its simplicity — once you know what you’re doing basic home coffee roasting ranks in difficulty somewhere between boiling an egg and making a good white sauce — why don’t more people do it? Why isn’t home coffee roasting already as popular as home baking, for example, or home pasta-making, or — for that matter — home corn popping?

First, because most people simply don’t know how vibrant truly fresh coffee tastes when compared to the partly-staled version we usually drink. Almost everyone knows how exquisite fresh bread is, or how much better home-popped popcorn is than the chewy, rubbery stuff that comes in bags. But the fragrance of coffee a day out of the roaster is a virtually forgotten pleasure.

Second, people don’t know that roasting coffee at home is easy, fun, and something that everyone did before the victory of advertising and convenience foods.

The Return to More Authentic Foods
By mid-20th-century Americans had begun to think of “coffee” as granulated brown stuff that comes from a can rather than the dried seeds of a tree requiring only a few relatively simple procedures to transform it into a beverage.

In the world of coffee the return to more authentic foods took the form of the specialty coffee movement, which sells freshly roasted coffee beans in bulk and encouraged coffee lovers to take their beans home and grind them themselves.

There is no doubt that whole bean coffees handled well are a tremendous advance in flavor and variety over supermarket packaged blends, and certainly anyone not yet introduced to the adventure of fine coffee should start by simply buying whole bean coffee at the local coffee specialty store, learning to grind and brew it properly, and experiencing some of the variety and pleasures it affords.

However, for the committed coffee aficionado I suggest that home coffee roasting is a logical next step toward closer intimacy with the bean and a mastery of one’s own pleasure.

Nostalgia, Balconies and Roasting Smoke
Throughout most of coffee history people roasted their own beans. Even in the United States, the cradle of convenience, pre-roasted coffee did not catch on until the latter years of the 19th century. Home-roasting persisted in Mediterranean countries like Italy until well after World War II. Many coffee drinkers in the Middle East and the horn of Africa still roast their own coffee as part of a leisurely ritual combining roasting, brewing, and drinking in one long sitting.

For people in countries where home roasting was the norm through the first half of the 20th century the practice is rich with nostalgia. Listen to Eduardo De Filippo, for example, a well-known Italian writer and performer, recollecting coffee roasting in his childhood Naples in Mariarosa Schiaffino’s book Le Ore del Caffe [AAAe]:

In 1908 … in the streets and alleys of Naples, in the first hours of the morning, a very special ritual was celebrated, a ritual indispensable to less wealthy families as well as to better-off aficionados: the ceremony of coffee roasting. It saved money to buy raw coffee beans and then roast then at home, the only cost being personal skillfulness and patience. Every week (or every couple of weeks) a quantity of coffee was roasted, depending on the needs, finances, and appetites of each family.

And since these rituals were not simultaneous, every day somewhere in the neighborhood a woman or grandpa could be found sitting on the family balcony, turning the crank of the abbrustulaturo, or coffee roaster.

By the way: Why did I mention balconies? Because in the process of such roasting the coffee beans, which are quite oily, release an intense smoke that could be quite unbearable in a closed space, yet no nuisance at all out-of-doors. Instead, dispersed in the air and transported by the wind, it was a source of great happiness for the entire neighborhood.

As for me — lingering about in bed during those early hours, trying to delay the moment when I would have to get up and go to school — as soon as this seductive smell reached my nose (it even penetrated the closed windows!) I would jump out of bed full of energy, happy to begin the day. And so it was that, even before I was allowed to drink it, coffee became my wake-up call and symbol for the new day …

Also, quite often, just before being swallowed up by the school gate, my ear would intercept an “Ahhhh…!” from a shoemaker nearby. Sipping his cup of coffee before starting work, his “Ahhhh…!” was so expressive — you could feel pleasure, satisfaction, happiness, appetite, even surprise and wonder. Later, as an adult, I would discover all of those things in coffee myself …

Some Reasons to Roast
For those of us who weren’t raised with the scent of roasting coffee filling the narrow streets and picturesque balconies of memory, and whose childhood recollections instead involve tract homes, Pepsi-Cola and Maxwell House, what are the advantages of home roasting? It may be a simple but forgotten art, yet why bother at all?

Here are a few reasons: Freshness and flavor. Unlike stale bread, which rapidly becomes dramatically inedible, stale coffee can still be drunk and enjoyed. But what a difference a few days make! An absolutely fresh coffee, a day or two out of the roaster, explodes with perfume, an evanescent aroma that seems to resonate in the nervous system and vibrate around the head like a sort of coffee aura. The aftertaste of a truly fresh coffee can ring on the palate for an entire morning; the taste of a week-old coffee will vanish in a few minutes.

Reasonably fresh coffee can be gotten at specialty stores if the roasting is done on the premises or close by, but with the growth of mammoth regional and national specialty coffee chains beans may be roasted hundreds or even thousands of miles from the store where you finally buy them. Coffee from these specialty chains will be infinitely better and fresher than the pre-ground stuff that comes in cans and bricks, but it won’t — can’t — be as fresh as the coffee you roast in your own kitchen.

Personal satisfaction. Roasting coffee at home provides the gratification many of us derive from outflanking consumerism by gaining control of a heretofore mysterious process that was once imposed on us by others. Home roasting is also an art. A minor one perhaps, but an art nonetheless, and one that can provide considerable gratification.

Money. Obviously this issue is more important to some of us than to others. Depending on how and where you buy your green coffee, you can save anywhere from 25% to 50% of the cost per pound by roasting at home.

Connoisseurship. The way to truly understand a coffee is to roast it. Furthermore, home roasting makes it possible to develop what amounts to a cellar of green coffees. Unroasted coffee doesn’t quite last indefinitely, but for a year or two it registers only subtle changes in flavor, and remains interesting and drinkable for some time after that. Thus you can keep modest supplies of your favorite coffees around and select them for roasting according to your mood and your guests’ inclinations.

Bragging rights. So there you are, roasting a blend of Guatemalan Huehuetenango and Sumatran Lintong, your kitchen pungent with smelly yet glamorous smoke, when your friends arrive for dinner carrying that pathetic bag of week-old house blend from down the street…

Romance. Finally, roasting your own coffee carries you deeper into the drama and romance of coffee. That romance is nowhere as vividly encapsulated as in that moment when a pile of hard, almost odorless grey-green seeds is suddenly and magically transformed into the fragrant vehicle of our dreams, reveries, and conversation.

If You Can Read You Can Roast
And above all: you can do it. You couldn’t get a job as a professional coffee roaster because professional roasters need to achieve precision and consistency as well as quality.

But anyone who can read this book can produce a decent to stunningly superb roast at home. Jabez Burns, probably the single greatest roasting innovator in American history, once said that some of the best coffee he had ever tasted was done in a home corn popper.

End of Chapter 1

 

Chapter 2 – Roasting History
The discovery that the seeds of the coffee fruit tasted good when roasted was undoubtedly the key moment in coffee history. It marked the beginning of the transformation of coffee from an obscure medicinal herb known only in the horn of Africa and Southern Arabia to the most popular beverage in the world, a beverage so widely drunk that today its trade generates more money than any other commodity except oil.

Mysterious Origins
When European travelers first encountered the beverage in the coffeehouses of Syria, Egypt and Turkey in the 16th century, the beans from which it was brewed came from terraced fields in the mountains at the southern tip of the Arabian peninsula, in what is now Yemen. Consequently, when the European botanist Linnaeus began naming and categorizing the flora of the astounding new worlds his colleagues were encountering, he assigned the coffee tree the species name Coffea arabica.

No one knows how Coffea arabica first came to be cultivated, when, or even where. Some historians assume that it was first cultivated in Yemen, but a strong case has been made that it was first deliberately grown in its botanical home Ethiopia, and was carried from there to South Arabia as an already domesticated species, perhaps as early as AD 575.

Considerable speculation has been focused on what finally led someone in Syria, Persia, or possibly Turkey to subject the seeds of the coffee fruit alone to a sufficiently high temperature (around 465F/240C) to induce pyrolysis, thus developing the delicate flavor oils that speak to the palate so eloquently and are undoubtedly responsible for the eventual cultural victory of coffee.

Ottoman Turks were the main instigators of the spread of coffee drinking and technology, since their expanding empire facilitated cultural and commercial exchange.

By 1550 coffee seeds or beans were definitely being roasted in the true sense of the word in Syria and Turkey, and the spectacular rise of roasted coffee to worldwide prominence in culture and commerce had begun.

Ceremonial Roasting
Early coffee roasting in Arabia was doubtless simple in the extreme. We have no detailed accounts of these earliest of roasting sessions, but they probably resemble the practices still found in Arabia today, and recorded by Europeans like William Palgrave in 1863 in his Narrative of a Year’s Journey Through Central and Eastern Arabia:

… Among the inhabitants of the Arabian peninsula roasting, pulverizing, brewing and drinking the coffee all were (and often still are) performed in one long, leisurely sitting. Both roasting and brewing are carried out over the same small fire. The roasting beans are stirred with an iron rod flattened at one end. After cooling they are dumped into a mortar, where they were pulverized to a coarse powder. The coffee is boiled, usually with some cardamom or saffron added, then strained into cups. It is drunk unsweetened.

From Brown to Black: A New Coffee Cuisine
Arabians roasted their coffee a rather light brown color. At an early point in coffee history, probably before 1600, a somewhat different approach to coffee roasting and cuisine developed in Turkey, Syria, and Egypt. The beans were brought to a very dark, almost black color, ground to a very fine powder using either a millstone or a grinder with metal burrs, and boiled and served with sugar. No spices were added to the cup, and the coffee was not strained, but delivered with some of the powdery grounds still floating in the coffee, suspended in the sweet liquid. It was served in small cups rather than the somewhat larger cups preferred by the Arabians.

This coffee cuisine is called “Turkish.” Why Turkish? Why not Egyptian, for example, or Syrian? Because this cuisine penetrated Europe via contacts with the Ottoman Turks, first through Venice into Northern Italy, and later through the Balkans and Vienna into Central Europe. Early European coffee drinkers all roasted their coffee very dark and drank it in the “Turkish” fashion, boiled with sugar.

Coffee Goes Global
The 17th and early 18th centuries saw the habit of coffee drinking spread westward across Europe and eastward into India and what is now Indonesia. As a cultivated plant it burst out of Yemen; first a Muslim pilgrim carried it to India, then Europeans took it to Ceylon and Java. From Java they carried it to indoor botanical gardens in Amsterdam and Paris, then as a lucrative new crop to the Caribbean and South America, where in a few short decades millions of trees were providing revenue for plantation owners and merchants and mental fuel for a new generation of philosophers and thinkers gathering in the coffeehouses of London, Paris, and Vienna. For more information about the Odyssey of the Bean Click Here

Roasting in a Technological Rut
Despite these dramatic developments in coffee drinking and growing during the 17th and 18th centuries, roasting technology itself changed very little. The most common approach was a simple carry-over from Middle-Eastern practice. Beans were put in an iron pan over a fire and stirred until they were brown. Somewhat more sophisticated devices tumbled the beans inside metal cylinders or globes that were suspended over a fire and turned by hand. Some of these apparatus could roast several pounds of coffee at a time and were used in coffeehouses and small retail shops; others roasted a pound or less over the embers of home fireplaces.

Roast Style and Geography
Taste in darkness of roast doubtless differed from place to place according to cultural preference, much as it does today. In most of Europe during the 16th and 17th centuries coffee continued to be roasted in dark, Turkish style. A pamphlet from 17th century England, for example, advises coffee lovers to “…take what quantity [of coffee beans] you please and over a charcoal fire, in an old pudding pan or frying pan, keep them always stirring til they be quite black…”

At some point, however, tastes in Northern Europe — Germany, Scandinavia and England — modulated to a lighter roast than the rest of Europe, which retained a preference for somewhat darker roasts deriving from the Turkish tradition. This distinction carried over to the New World: North Americans largely adopted the lighter roasts of the dominant Northern European colonists and Latin Americans the darker roasts of their Southern European colonizers. Arabia and parts of the horn of Africa retained their original taste for a lighter roast coffee, drunk with spices but without sugar. For Information About “How To Roast Coffee” Click Here

Enter the Industrial Revolution
As the 19th century began coffee was roasted in small, simple machines, either at home or in shops and coffeehouses. By the end of the century the new urban middle class was increasingly buying a coffee roasted in large, sophisticated machines and sold in packages by brand name.

Further technical innovations focused on two problems: 1) controlling the timing or duration of the roast with precision, and 2) achieving an even roast from bean to bean and around the circumference of each individual bean.

Starting in 1867 fans or air pumps were introduced to automate the cooling. The beans were dumped into large pans or trays. While machine-driven paddles stirred the beans fans pulled cool air through them, both reducing their surface temperature and carrying away the smoke produced by the freshly roasted beans.

The second technical problem was addressed when toward the end of the century hot air was drawn through the drum by a fan or air pump, often the same fan or pump used to pull air through the beans to cool them. The combination of moving air and vanes tossing the coffee meant the coffee was roasted more by contact with hot air than through contact with hot metal, improving both the consistency and the speed of the roast.

20th Century Innovations
Obviously the 20th century could not leave coffee roasting technology alone. In 1934 the Jabez Burns company developed a machine that applied no heat whatsoever to the drum itself, instead relying entirely on a powerful stream of hot air howling through the drum.

Roasting Without End: The Continuous Roaster
For large roasting companies time is money, and emptying beans from the roaster and reloading with more beans takes time. Such economic motives lay behind still another 20th century development, the continuous roaster, in which the roasting process never stops until the machine is turned off.

The most common continuous roasting design elongates the typical roasting drum and puts a sort of screw arrangement inside it. As the drum turns the screw-like vanes transport the coffee from one end of the drum to the other in a slow, one-way trip. Hot air is circulated through and across the drum at the front end and cool air at the far end. The movement of the beans through the drum is timed so that green coffee entering the drum is first roasted, then cooled by the time it tumbles out at the end of its journey. Variations of this principal continue to be employed in machines used today in many large commercial roasting establishments. For More Information About “Commercial Roasting” Click Here

A Revolution in Measurement and Control
As we approach the 21st century there are signs that roasting technology may be undergoing still another revolution. Barring some breakthrough in the use of microwaves, it seemed unlikely that the basic technologies for applying heat to the beans and keeping them moving will change. What is changing is the way the roast is monitored and controlled.

Traditionalists: Nose and Eye
Traditional roasters rely on the eye, carefully observing the developing color of the roast by means of a little instrument called a trier, which they insert through a hole in the front of the roasting machine to collect a sample of the tumbling beans. The decision when to stop the roast is based on the color of the beans read in light of experience. Adjustments to the temperature inside the roast chamber also may be made on the basis of experience, experience both with roasting generally and with the idiosyncrasies of specific coffees.

Science Sneaks Up on Art
What was once a matter of art and the human senses, however, is increasingly becoming a matter of science and instrumentation, in which individual memory is replaced by an externalized, collective memory of numbers and graphs.

Some extremely sophisticated roasting apparatus is now being constructed with spectrophotometers built into the roasting chamber, so that the gradually deepening color of the roast appears translated as a series of numbers on a display, and the roast can be terminated precisely and automatically on the basis of a predetermined color reading.

But It Still Needs to Be Tasted
One human sense that hopefully will never become obsolete is taste. For even if the day arrives when roasting is performed entirely on the basis of system and number, the roaster (or roastmaster as he/she is increasingly called in these up-scale days) still will need to taste the coffee when it comes out of the roasting apparatus and make some informed adjustments to those numbers based on personal preference and roasting philosophy. Thus the variety of taste achieved by different approaches to roasting may continue to surprise our palates and enrich the culture and connoisseurship of coffee. And roasting, perhaps, will remain art as well as science. For More Information About “Coffee Tasting” Click Here

Social History: Quality Makes a Comeback
To conclude, let’s return to the social history of roasting and bring it to its rather surprising conclusion in the 20th century.

Although pre-roasted, pre-ground coffee sold under brand names claimed more and more of the market in industrialized Europe and America during the first half of the 20th century, older customs hung on. In southern Europe many people continued to roast their coffee at home well into the 1960s, and even in the United States numerous small, storefront roasting shops survived.

By the 1960s packaged coffee identified by brand name dominated the urbanized world. A few storefront roasters hung on here and there in larger cities, but the simple process of home roasting became a lost art, pursued in industrialized societies only by a handful of cranky individualists.

The few surviving shops that still roasted their own coffee and sold it in bulk provided a foundation for a revival of quality coffees that has taken on an extraordinary power in the United States, and in many other parts of the industrialized world.

This revival is usually called the specialty coffee movement. Thus the end of the 20th century is witnessing a return to people buying coffee in bulk and grinding it themselves before brewing. Perhaps the United States, which led the world down the superhighway of convenience, may be pointing it back along the slower road toward quality and authenticity.

Quirky and Individualistic
Starbucks is in many ways a happy marriage between the quality-conscious idealism of the specialty coffee movement and rigorous corporate power and discipline. Nevertheless it does not entirely represent the world of coffee as I would like to see it enter the 21st century: quirky and individualistic, with local roasters selling their own style of coffee in their own neighborhoods, a world full of choice and surprises.

For those who really love coffee, the moment may have come to leave cans and enormous coffee store chains behind and enjoy coffee as people did before the advent of brand names, chain stores and advertising: by roasting your own.

End of Chapter 2

 

Chapter 3 – Roast Styles
Nothing influences the taste of coffee more than roasting. The same green coffee can be roasted to taste grassy, taste baked, taste sour, taste bright and dry, taste full-bodied and mellow, taste rounded and bitter-sweet, taste charred. In appearance roasted beans can range from light brown with a dry surface through dark brown with an increasingly oily surface to black with an almost greasy look.

Changing Roast Traditions
Until recently preferences in roast style, like so many other cultural choices, were traditional. Traditional preferences are the basis of many of the names used in the contemporary American coffee business to describe style of roast: New England (light), American (medium), Viennese (slightly darker), French (still darker), Italian (still darker again), etc.

What’s Best?
It is difficult to determine “best” style of roast. One of the many pleasures of home roasting is experimenting for yourself to determine what the “best” roasting style is for you. Of course one of the frustrations of home roasting is that once you get a batch of beans that tastes exactly the way you want them to you may have trouble precisely duplicating the procedure that produced them. But if you are at all systematic you can come very close to consistency, and home roasting is for romantics and adventurers anyhow. Those concerned purely with uniformity probably should stick to buying coffee from the store.

Bad by Any Standard
There are some clear parameters to good roasting, however, boundaries which, if transgressed, produce roasts that are bad by almost anyone’s standard.

In roasts that are too light, in which the internal temperature of the beans never rises above 390F and the color remains a pale brown, the flavor oils stay undeveloped and the coffee will taste grassy, sour, and without aroma. In roasts that are too dark, in which the internal temperature of the beans has soared above 480F and the color is definitely black, most of the flavor oils will have been burned out of the bean and the woody parts of the bean itself may be charred. Such coffee tastes thin-bodied, burned, and industrial.

Another way coffees can be roasted definitively badly is either by baking them by holding them too long at too low a temperature, or by scorching the outer surfaces of the beans. Both mistakes are easy to commit for beginning home-roasters.

But so long as a roast avoids such extremes, only cultural preference and personal taste can determine which style is ultimately “best.”

Names and Roast Styles
Currently-used names for roast styles come from two sources. One source is the general roasting preferences of various nations of coffee drinkers — Italian, French, etc. The other grew up within the American coffee profession during the late 19th and early 20th centuries.

Geographical Roast Names
Let’s take a quick run through the common roast names first, beginning with those that derive from coffee-drinking geography, since these are the names you are most likely to see on coffee bags and bins.

New England (light brown, dry surface)

American (medium brown, dry surface)

Viennese (medium dark brown, possibly flecks of oil on surface)

French (moderately dark brown, light oil on surface)

Espresso (dark brown, surface can range from very oily to barely slick depending on roast procedure)

Italian (dark, blackish brown, definite oily surface; most roasting establishments stop here)

Dark French or Spanish (very dark brown, almost black, very oily).

Traditional American Roast Names
There is another naming system haunting the aisles of coffee stores, however, one based on traditional American roasting terminology stretching back to the 19th century. It breaks out about like this:

Cinnamon (very light)

Light (light end of the American norm)

Medium

Medium-high (American norm)

City; high (slightly darker than norm)

Full city (definitely darker than norm; sometimes patches of oil on surface)

Dark (dark brown, shiny surface; equivalent to espresso or French)

Heavy (very dark brown, shiny surface; equivalent to Italian).

Numbers to the Rescue: The Agtron/SCAA Roast Color Classification System
The Specialty Coffee Association of America (SCAA) has recently released a kit for classifying roast based on precise machine reading of color.

The eight reference points in this classification system have no names, only numbers, and are matched with eight color disks. A sample of a roasted coffee can be matched with a color disk, thus assigning it an approximate number on a scale variously termed a chemistry index or Agtron gourmet scale. These color-disk (or color-tile) numbers run from #95 (lightest roast) through #85 (next lightest) at intervals of ten down to #25 (darkest common roast).

Talking About Taste
Here are a few of the most important terms for talking about differences in taste among green coffees and roast styles. I’ve disregarded popular terms that are self-evident or have no clear, consensus meaning (rich, floral, fruity, buttery, etc.).

Acidity; acidy – One of the most important tasting categories in coffee, and one of the most likely to be misunderstood. Neither acidic nor sour, an acidy coffee is brisk and bright. The darker a coffee is roasted, the less acidy it becomes. However, strong acidity in a green coffee may show up in a dark roast as sharpness or pungency.

Body; mouthfeel – Body is the sensation of heaviness in the mouth; it also registers as a rich, full feeling at the back of the palate. Body is a sensation, an element of taste, not a measurable fact. As coffee approaches a medium-to-dark brown roast, body increases. As it passes into a very dark roast (Dark French or Spanish roast) body decreases.

Aroma – Although this term is self-evident in its general definition, it is important in discussions of roast. Aroma is less developed in very light roasts, peaks in intensity in medium to medium-dark roasts, and falls off in very dark roasts.

Complexity – Another obvious yet useful term. A complex coffee allows certain strong sensations such as acidity and sweetness to coexist. It presents a wide range of sensation, and often doesn’t reveal itself immediately and definitively. Complexity is undoubtedly at its peak in the middle ranges of roast style, from medium through the moderately dark to dark roasts used for espresso. Most blends aim to increase complexity.

Depth – Depth describes the resonance or sensual power behind the sensations that drive the taste of the coffee. It is a tricky and subjective term, but it tries to get at the way certain coffees open up and support their sensations with a sort of ringing, echoing power, whereas others simply present themselves to the palate and then stand pat or even fade.

Varietal distinction, varietal character – These terms seem to have migrated over to coffee from wine-tasting relatively recently. They describe qualities that distinguish one unblended, green coffee from another when the coffees are brought to the relatively light “cupping” roast used in professional coffee evaluation.

Balance – Describing coffees in which the acidity is strong but not overwhelming, the body substantial, and no taste idiosyncrasy dominates.

Wild; natural; earthy – A slight sour twist to the acidity is the best verbal description I can produce. Once you identify this taste syndrome you’ll know it forever. I enjoy wild-tasting coffees; they remind me that I’m drinking something that comes from the earth. But I’m a romantic. If this taste is too pronounced it becomes an outright defect.

Clean – In some respects this term describes qualities that are the opposite of wild or natural. Clean-tasting coffees are free of defects, shadow undertones, or varietal distractions.

Roast-Related Terms
These are words specifically related to the overlay of taste that style or degree of roast contributes to green coffees.

Sweet – In medium-dark through moderately dark roasts (Viennese through espresso) the development of sugars combined with the partial elimination of certain bitter flavor components like trigonelline give the cup a rounded, soft taste and rich body without flatness. Some coffees come to a sweeter dark roast than others.

Pungent, pungency – These words are my choice to describe the distinctive, bitterish twist that dark-roasting contributes to taste. Any lover of dark roasts knows and honors this sensation.

Roast taste; bittersweet – Terms describing the characteristic collective flavor complex of darker roasts. The acidy notes are gone, replaced by pungent notes combined with a subtle, caramel sweetness. Bittersweet is my term; some people call this often unnamed group of sensations roast taste or the taste of the roast.

Bready – A bready taste manifests in coffees that have not been roasted long enough or at a high enough temperature to bring out the flavor oils.

Baked – Another term for maltreated coffee. The coffee has been held too long in the roaster at too low a temperature; the taste in the cup is flat and without aroma.

For additional coffee terminology Click Here to access our comprehensive Coffee Glossary

Roast Styles and Flavor
Now let’s look at how some of these key categories — acidity, body, aroma, varietal distinction, and roast taste — transform as coffee is brought in stages from a very light to a very dark roast style.

The most lightly roasted coffee (usually called cinnamon; internal bean temperature at conclusion of roast below 400F; SCAA color tile #95) is very light brown in color, will display a strong, sometimes sour acidity, little aroma, an often grainy taste, and thin body. The surface will be dry.

As the coffee achieves a more complete but still relatively light roast (New England, light; concluding internal bean temperature around 400F; SCAA color tile #85), the acidy notes will be powerful, and the varietal characteristics, which often are nuances of acidity, will be pronounced. The body will be developed, but not as fully as it will become in a somewhat darker roast. The surface of the bean remains dry, as the flavor oils continue to develop in tiny pockets inside the bean.

At a moderately light to medium-brown roast (light, medium, American; concluding internal bean temperature between 400F-415F; SCAA color tiles #75 through #65) the acidity will be bright but less overpowering, the varietal characteristics still pronounced, and body fuller. For most traditional East-Coast American coffee-drinkers this style represents a “good” coffee taste.

At a slightly darker, medium-brown roast (medium, medium high, American, city; concluding internal bean temperature 415F-435F; SCAA color tile #55) acidity remains strong though perhaps richer, varietal characteristics muted but still clear, and body still fuller. This is the traditional roasting norm for most of the American west.

At a full city, often labeled Viennese roast (concluding internal bean temperature 435F-445F; between SCAA color tiles #55 and #45), acidity is slightly more muted and body slightly heavier. The surface of the bean may remain dry, or oils may appear in tiny droplets or patches as they begin to rise from pockets inside the bean to its surface.

At a moderately darker roast (espresso, European, high; concluding internal bean temperature 445F-455F; between SCAA color tiles #45 and #35), the acidity is largely folded into a general impression of richness, the varietal characteristics muted virtually beyond recognition, the body full, and the bittersweet notes characteristic of dark-roasted coffees rich and resonant. At this roast the surface of the bean always displays some oil, ranging from a few droplets to a shiny coating.

When coffee is brought to a definitely dark roast (French, Italian, dark; concluding internal bean temperature 455F-465F; SCAA color tile #35) the bittersweet or dark roast taste completely dominates, the body begins to thin again, and all remaining varietal character and acidy notes are transmuted inside the pungent richness of the dark roast flavor, which may range from rounded and mellow (in less acidy coffees) to bordering on bitter (in coffees that begin very acidy). The surface of the bean will be bright with oil.

With very dark brown roasts (Italian, Dark French, Spanish, heavy; concluding internal bean temperature 465F-475F; between SCAA color tiles #35 and #25) the body continues to thin as more and more of the oils are evaporated by the roast, the bitterish side of the bittersweet equation becomes more dominant, and a slight charred taste may appear. The bean is shiny with flavor oils driven to the surface.

The ultimate dark roast, almost black (Dark French, Spanish; concluding internal bean temperature 475F-480F; SCAA color tile #25) is definitely a special taste. The body is even thinner, more bitter and less sweet, and burned or charred notes dominate. All coffees regardless of origin tend to taste about the same. The surface of the bean is bright with oil. Home roasters typically have an opportunity to sample this ultimate dark roast, since sooner or later we all produce a batch whether we plan to or not.
Beyond this point the coffee is definitively burned: it has no body, tastes like charred rubber, the oils are driven off the surface of the bean, and the roast is worthless.

Time/Temperature Ratio and Other Subtleties
All roast styles differ in taste depending on how the roast is achieved. Coffee brought to a given roast color quickly — by higher roast temperature or a combination of higher temperature and rapidly moving air currents — will usually preserve more acidy notes than will coffee brought to the same degree of roast at lower air temperatures over a longer period of time. On the other hand, a slower roasted coffee tends to be fuller in body and more complex in taste.

Time/Temperature Ratios and the Home Roaster
Your ability to experiment with subtler taste differences related to the way you achieve a given roast style depends above all on the equipment you use.

I propose four technologies for home roasters in Home Coffee Roasting: 1) stove-top crank corn poppers; 2) hot-air corn poppers and similar fluid-bed roasting devices; 3) gas ovens; and 4) electric convection ovens. Each tends to produce a roast emphasizing certain taste characteristics.

Those who like a bright, acidy coffee are probably best served by a fluid-bed roasting technology as represented in hot-air corn poppers and similar home roasters.

Those who like a more idiosyncratic roast taste with heavier body and a fuller profile may be best off with an old-fashioned stove-top corn popper that achieves a given roast more slowly and allows the roasting smoke to work around the beans.

Coffees prepared in gas ovens often display a striking complexity and depth of flavor because the irregularity of the roast coaxes a wider range of taste out of the coffee than do methods that produce a more regular, uniform roast. The relatively long roast times in gas ovens also promote a rather full body and relatively rounded, low-acid flavor profile.

Finally, there are electric convection ovens. The extremely long, slow roast produced by these appliances creates a clean-tasting, full-bodied, but very low-acid cup. Coffees roasted in electric convection ovens will taste dull to most palates, although some may enjoy their gentle, understated sweetness.

Green Coffee Characteristics and Roast Style
The moisture content and hardness of green coffee beans effect how quickly they roast and how they respond to various roast temperatures. The moister and denser the bean the somewhat slower it will roast and/or the higher the temperature needs to be in the roast chamber. More technically inclined roasters precisely measure the density and/or moisture content of the bean and modify their roasting procedure accordingly.

Such exact accommodations are not an option for most home roasters. However, there are a few rules of thumb based on the age of a green coffee and how it has been handled that can be usefully followed by the home roaster. These are included in later excerpts from Home Coffee Roasting.

End of Chapter 3

Chapter 4 – Choosing Green Beans
Every green coffee holds in its vegetable heart a slightly different collection of secrets. One of the pleasures of roasting at home is becoming acquainted with those intimacies in a far more direct and active way than by simply tasting someone else’s roasted coffees.

Green Coffee Basics
The world’s coffees are many and their differences complex. What follows is a very general orientation to selecting green coffees from the point of view of the home roaster. Keep in mind that the ultimate test of a coffee is not its name, or its grade, or any of the rest of the muttering that we attach to things, but rather its taste. If you try it and like it, then it’s a good coffee, no matter what I say. And if you don’t like it, then you should be prepared to ignore all of the pontificating that tries to convince you otherwise.

Narrowing the Field: Species
Botanists now recognize approximately one hundred species of coffee plant, but only one, Coffea arabica, is the source of all of the world’s most celebrated coffees.

The coffee species second in importance is Coffea robusta, or Coffea canephora as it is known to botanists. Robusta grows at lower altitudes than arabica and is more disease resistant. Robustas generally lack the acidity and complexity of the best arabica coffees. They are used mainly as unnamed constituents of the cheaper coffee blends. Small quantities of better quality robustas are sometimes used to give body and sweetness to some espresso blends.

The Question of Coffee Names
Fancy or specialty coffees are sold in two forms: blends, mixtures of coffees from more than one crop or region, and unblended coffees from a single crop and region (often called straight or varietal coffees). Unblended coffees are of most interest to home roasters because they facilitate knowledge (you know what you’re roasting), adventure (they often taste intriguingly different) and control (once you get a feel for various individual coffees you can begin to assemble your own blends).

Let’s look at each of these naming categories:
Country of Origin

This designator (Kenya, Colombia, etc.) is easy to understand. It is usually the one descriptive term that always appears on store labels and coffee bags. However, countries are large, coffees in any given country are many, and market forces complex. Hence the various names and categories that follow. For more information on Coffee By Country Click Here.

Market Names

A market name is a traditional identifier that appears on burlap coffee bags and on exporters’ and importers’ lists. Most market names refer to region (Guatemalan Antigua or Mexican Oaxaca), a few to a port through which the coffee is traditionally shipped (Brazilian Santos) or even to a port through which the coffee once was shipped but isn’t any more (Yemen Mocha; Mocha is a now closed and forgotten port on the Red Sea).

However, market names ultimately describe a coffee, not a place. Market names carry specific associations that include not only growing region, but certain taste characteristics. Some market names are more famous than the country of origin. Hawaiian Kona coffee is typically known by its market name, Kona, not by its country of origin, United States, or even by its state of origin, Hawaii.

Layers of Grade Names

Coffee is also sold by grade (Kenyan AA, Colombian Supremo, etc). Grade names can be based on evaluative criteria ranging from how big the bean is, to how high the coffee is grown, to how good it tastes (cup-quality).

Bulking coffee in large generic lots according to grade traditionally has been a way for coffee bureaucracies of growing countries to maintain centralized control over the coffee enterprise. However, the discipline of regulation as embodied in grading standards is being replaced or supplemented by the discipline of the market as embodied by competition among individual growers and grower associations for the attention of roasters and buyers in consuming countries.

Nevertheless, grade names remain an important element of coffee nomenclature. The more informative coffee store may identify a coffee by country (Guatemala), by market name (Antigua) and finally by grade (Strictly Hard Bean). As a rule, however, stores qualify the country name of a bulk coffee with only one adjective, either grade or market name.

Processing Method

The coffee bean is actually a seed of a small fruit coffee people call a cherry. How the fruit is removed from the bean and how the bean is dried are steps collectively known as Processing. Processing is one of the most important influences on coffee quality and taste.

In the wet method the various layers of skin and fruit around the bean are stripped off, before the bean is dried. Wet-processed or washed coffees tend to be more consistent, cleaner and brighter or more acidy in taste than dry-processed, natural or unwashed coffees, which are dried with the coffee fruit still adhering to the bean. The dried fruit is subsequently removed from the dry beans, customarily by machine. Dry-processed coffees are generally more idiosyncratic in flavor and heavier in body than wet-processed coffees.

Semi-washed coffees are a sort of compromise. The skin of the cherry is removed immediately after picking, but the flesh or pulp is allowed to dry on the bean. The dried pulp is later stripped off by a machine that temporarily wets the bean again. Some have argued that semi-washed coffees felicitously combine the full body and complexity of dry-processed coffees with the clarity and acidity obtained by the wet method.

How coffees are dried also may affect flavor and quality. As a rule, sun-dried coffees are considered preferable to machine-dried coffees.

Growing Conditions and Grade Names

Finally, the altitude at which coffee is grown figures in many grade names. Arabica coffee beans grown at higher altitudes typically mature more slowly than beans grown at lower altitudes, and the resulting denser bean may display more acidity and sometimes more complexity in the cup. Certainly growing altitude is only one aspect of many that influence coffee quality and flavor.

Organic is an important descriptive term in the contemporary coffee world. An organically-grown coffee must be certified by an international agency as having been grown without synthetic chemical fertilizers, pesticides, or herbicides. Somewhat lower yields and the considerable cost of the certification process account for the higher prices demanded for many organic coffees.

Estate and Cooperative Names

Owners of quality-conscious coffee farms enlist the aid of their colleagues in consumer countries to establish estate identities for their coffees. Estates sell their coffees directly to dealers without mixing them with other coffees from the same region, in theory insuring that these coffees reflect consistent growing conditions and processing practices.

A similar consistency is achieved by some cooperatives of smaller growers which market their coffees separately like estates through special arrangements with coffee dealers or roasting establishments. These designated cooperative coffees often support environmental and/or social agendas.

Some Good Things about Estate Coffees
Advantage number one: The estate concept helps identify coffees in precise terms. If you buy the same coffee a second time it most likely will display the same characteristics that attracted you to it in the first place.

A second advantage to buying by estate is that you can select coffees according to specific growing practices, social practices, or processing techniques.

A third advantage to estate coffees is that many offer superior or distinctive versions of regional taste characteristics.

Some Less-than-Good Things about Estate Coffees
Disadvantages to buying coffee by estate or cooperative?

Above all, if you become too concerned with buying only estate coffees you’re limiting yourself. There are many outstanding coffees that simply are not marketed by estate.

A second disadvantage: price. Estate coffees may be good or different, but they may not be good or different enough to warrant the considerably higher price often asked for them.

Finally, some estate and designated cooperative coffees may be difficult to find green. Estates and cooperatives tend to work through a few selected wholesale roasters or dealers, sometimes only one, so access to these coffees is often limited.

Old vs. New: Names for Botanical Variety
All fine coffees derive from the arabica species, but not all coffees derive from the same botanical variety of that species. The fine coffee world is only beginning to market coffee by variety (or strain).

The connoisseurs and traditionalists raise the banner of what they call old arabica varieties, while some scientists, coffee growers, and government officials defend the usefulness of new arabicas.

As the world of fine coffee grows more sophisticated botanical variety will figure more prominently in identifying and marketing coffees, and aficionados may be in a position to make their own assessment of the impact of botany on quality.

The Ultimate Challenge: Adding Roast Names
Style of roast also can figure in the names that appear on store labels and signs. Most straight, unblended coffees are offered in a “normal” American medium to moderately-darkroast, in which case the roast style is not named. However, if an unblended coffee is offered in a style darker than normal the name of the coffee and the roast style both may appear: Sumatran Mandheling Dark Roast, for example.

Circumnavigating the Coffee Globe
Classic Coffees: Latin America and Hawaii

At their best, the classic coffees of Latin-American and Hawaii manifest full body, bright acidity, and a clean, straightforward taste. Their taste is based in part on the clarity of flavor achieved through wet-processing. Almost all fine Latin-American and Hawaiian coffees are washed, the exceptions being the better dry-processed and semi-washed coffees of Brazil.

The Big Classics

Generally fine Costa Rican, Guatemalan, and Colombian coffees are “big” coffees: full-bodied, with a bracing, rich acidity. They are best enjoyed at a medium to medium-dark roast, so that the power and subtle nuances of their acidity can be enjoyed.

The Caribbean Classics

The finest Caribbean coffees (best coffees of Puerto Rico, Jamaica, the Dominican Republic, and coastal Venezuela) are also powerful, but generally lower-toned, with their acidity held inside a deep, sweet, long-finishing richness.

True Jamaican Blue Mountain coffee, like the original Wallensford Estate Blue Mountain, is a big, rounded, intense, yet perfectly balanced example of the classic Caribbean taste.

The Gentle Classics

Good Brazilian, Peruvian, and Mexican coffees generally are lively rather than overpowering in acidity, lighter in body than the bigger classic coffees, and rounded in flavor. They make excellent darker roasts for espresso drinks. Their gentler acidity also makes them attractive coffees for those who like to drink their coffee black and unsweetened. Other Central- and South-American coffees less often seen — from Nicaragua, Panama, Ecuador and El Salvador — also are typically softer, “smaller” versions of the classic taste.

The Hawaiian Classics

In the big picture Hawaiian coffees may be somewhat overpriced and perhaps a bit over-publicized. However, the best estate Hawaiian Kona is a powerful, rich, acidy example of the classic taste.

One of the great advantages of Hawaiian coffee for the aficionado is its accessibility. Growers are beginning to lavish the same attention on Hawaiian coffee as vintners did a couple of decades ago on California wines. It has become relatively easy to visit the farms, and proprietors increasingly provide plentiful and detailed information on their coffees.

Romance Coffees I: East Africa and Yemen

The coffees of Africa, Asia and the Malay Archipelago (Indonesia and Papua New Guinea) provide an array of romantic alternatives to the classic coffees of Latin America and Hawaii.

East Africa, together with Yemen, just across the Red Sea from Africa, produces some of the most distinctive of the world’s coffees. Most are characterized by an extraordinary wine-like acidity, which can range from rough and wild in dry-processed Ethiopian coffees (Harar, Jimma), to rich and robust in Kenyan, to earthy and subtle in Yemen Mocha coffees. Similar wine-like notes enliven excellent arabica coffees from Zimbabwe, Malawi and Uganda. Probably the best place for home roasters to begin in their exploration of East African coffees is Kenya. The state-of-the-art Kenyan coffee industry produces a plentiful yet superb product that is relatively easy to obtain green.

Ethiopia, the original home of Coffea arabica, produces the most varied range of coffee taste experience of any country — or indeed any region — in the world. Ethiopian Yirgacheffe is perhaps the world’s most remarkable coffee. It is full-bodied, soft and rich, but its most striking characteristic is its extraordinary floral perfumes.

A last note of clarification: There are many variant spellings in English of Ethiopian and Yemeni names. Mocha may also appear as Moca, Mocca or Moka; Harar as Harer, Harrar or Harari; Jimma as Djimah or Jima; Gimbi as Ghimbi; Yirgacheffe as Yrgacheffe.

Romance Coffees II: India, Indonesia, New Guinea

Coffees of the arabica species grown in a crescent stretching from southwestern India across the Indian Ocean through Sumatra, Sulawesi and Java to New Guinea offer another kind of romance: the intrigue of softness, richness, and heavy, resonant body. These qualities reach their peak in the best coffees of Sumatra and Sulawesi (old name Celebes), which wrap a deep-toned acidity inside their extraordinarily rich body.

Romance Coffees III: Aged and Monsooned Coffees

Some aged (also called vintage) coffees have been held for as long as ten or more years before being exported or roasted, although three years is probably the norm. Eventually aged coffees begin to lose all acidy notes and turn dull and syrupy rather than rich. Even these coffees can be a pleasant change of pace drunk straight, however, and a delight in blends.

A taste profile somewhat similar to aged coffees is achieved in considerably less time by Indian exporters who “monsoon” their coffee. This exotic process involves holding the coffee in special warehouses open to the moist monsoon winds. In a few weeks the coffee yellows and transforms in taste.

You may want to try an aged and a monsooned coffee, first straight in order to understand their taste, then perhaps in a blend, where the weight and body of specially handled coffees can be used as a resonant counterpoint to brighter origins.

For more information on Coffee By Country Click Here.

Blends and Blending
Coffee blends are crafted for two reasons: 1) to save money; 2) to produce a coffee that tastes better than (or at least different from) coffees of a single crop or region.

For large commercial roasters the cost issue is paramount. Since their coffees compete in supermarket chains, mass-market blenders attempt to create a decent coffee as cheaply as possible.

Specialty coffee roasters who sell smaller quantities of coffee in whole-bean form to a more demanding clientele also may want to cut costs by blending. But the primary goal of most specialty roasters is to produce a blend that tastes better or more balanced than any of its constituent coffees.

Other blends aim either to mimic characteristics of a famous and expensive coffee (Jamaican Blue Mountain Style Blend, meaning it has no Blue Mountain in it whatsoever), or stretch a costly coffee by mixing it with similar but cheaper beans (Hawaiian Kona Blend).

Blending at Home: Getting Started
For home roasters, subtlety in blending may only be possible after considerable tasting and experimentation. It is probably easier to get a feel for the process by combining very different but complementary coffees; a bright, acidy coffee with a fuller, deeper-toned coffee, for example.

To help that process along, here is a list dividing some well-known coffees into categories according to the particular qualities they might contribute to a blend. Obviously there are numerous ways of categorizing coffees for blending purposes; my list offers only one approach to a complex subject.

Category 1:
Big classic coffees. These coffees contribute body, powerful acidity, and classic flavor and aroma to a blend. They perhaps make too strong a statement for use as a base for blends, but are excellent for strengthening and energizing less acidy coffees with softer profiles. I’ve omitted more expensive coffees like Jamaican Blue Mountain, Hawaiian Kona, and Puerto Rican Yauco Selecto, which given their cost probably should be enjoyed straight.

Guatemala (Antigua, Coban[AAAa] and Huehuetenango, other good Guatemalan coffees)
Costa Rica (Tarrazu[AAAu], Tres Rios[AAAi], other good Costa Rican coffees)
Colombia
Venezuelan Tachira[AAAFIRSTa], Merida[AAAe]

Category 2:
Smaller classic coffees. These are “good blenders”; they establish a solid, unobtrusive base for a blend, and contribute body and acidity without competing with more individualistic coffees. When brought to a darker roast they often confer a satisfying sweetness.

Mexico (Oaxaca, Coatepec, Chiapas, Tapachula)
Dominican Republic or Santo Domingo
Peru (Chanchamayo for more acidity; Northerns for less)
Brazilian Santos (washed for more acidity, semi-washed for more body and sweetness)
Panama
Other possibilities are the better coffees from El Salvador, Ecuador, Nicaragua, Haiti and coastal Venezuela

Category 3:
East African and Yemen coffees. Their powerful wine-like acidity makes these coffees a poor base for a blend, but excellent contributors of complexity and liveliness. Some, like Kenya, contribute considerable body as well. These coffees should be used with care in blends for darker roasts; they add a sharp bite attractive to many (including me), but may be distracting to others.

Yemen Mocha (adds richness and body as well as acidity)
Kenya (ditto above; acidity even more powerful)
Zimbabwe
Ugandan Bugishu
Ethiopian Harar (contributes rough, fruity, exciting acidity, but less body than the above)
Malawi

Category 4:
Asian-Pacific and similar coffees. These add richness and body to a blend, and combine well with other coffees. Their deep-toned acidity will anchor and add resonance to the lighter, brisker coffees of category 2, and balance without blunting coffees in categories 1 and 3.

Sumatra
Sulawesi
Java arabica
New Guinea
Ethiopian washed coffees (best are Yirgacheffe and Limu)
Indian Mysore (unobtrusive; tends to add weight without power)

Category 5:
Aged and specially-handled coffees. These add weight and body to a blend, and in the case of aged coffees richness and complexity as well. They are fun to experiment with in blends as a balance to category 1 and 3 coffees.

Indian Monsooned Malabar
Any good aged coffee
For more information on Coffee By Country Click Here.

Blending for Taste and Variety
Clearly there are two ways to approach blending for taste alone: by system or by improvisation.

One systematic approach would be to start with a base coffee, as I suggest in the previous section, roast and drink it long enough to really know it, then experiment with adding other coffees to it, keeping notes as you go along. Another approach might be to begin with two coffees that complement one another, like the acidy Mocha and the softer, fuller Java of the original Mocha-Java blend (I’d make them a Kenya and a Sumatra, experiment with the proportions of the two constituents until you learn how they work together, then begin experimenting with adding a third coffee, again keeping notes so that a success can be built upon or duplicated.

Blending for Espresso and Dark Roasts
When blending for espresso cuisine the first question to consider is how you and your guests take your espresso. If you tend to drink it without milk and with very little sugar, you should avoid the big, acidy coffees in categories 1 and 3 and rely mainly on coffees in categories 2 and 4. Italian blenders prefer a base of Brazilian Santos, whereas West-Coast Americans typically rely on Mexican and Peruvian coffees. Good Indonesian coffees make splendid dark roasts, but are relatively expensive. Some Italians like to use high-quality robustas to smooth out their espresso blends.

On the other hand, if you drink your espresso with a good deal of hot milk and/or sugar, you may prefer a more pungent blend. On a base of Brazil, Peru, or Mexico, try adding a coffee from categories 1 or 3, perhaps either a Costa Rica or a Kenya or some of both. Go easy at first, adding a little more of the big, acidy coffee every session, until you achieve a taste you like for the way you drink your coffee. If you know you like an assertive, powerfully twisty espresso, start with a base of Kenya and gradually soften it with increasing amounts of a gentler coffee.

Of course how darkly you roast your espresso blend and what method you use to roast it also profoundly affects flavor.

Blends of Roasts
When I first came into coffee consciousness in the San Francisco Bay Area twenty years ago blends of dark- and medium-roasted beans were common. They are less so today, which is probably a pity. For me one of the most vibrant and exciting ways to enjoy a coffee is to mix darker and lighter roasted beans of the same origin, thus experiencing the coffee in its full range of roast taste.

Try it. Take the same coffee and bring two batches to a medium and to a dark or moderately dark roast, then blend the two. If you enjoy the result try varying the identity of the two coffees: Blunt the acidity of a Kenya by carrying it to a moderately darkroast, then combine one part of the darker-roasted Kenya with two parts of a medium-roasted Indonesian coffee, for example.

A Note on Decaffeinated Coffees
Coffees are decaffeinated in their green state. Three principal processes are used today in the world of fancy or specialty coffees: the traditional or European process, the water-only or Swiss-Water Process, and the CO2/water or Sparkling Water Process. All are consistently successful in removing all but a trace (2% to 3%) of the resident caffeine.

The traditional and water-only processes follow roughly the same steps: 1) The beans are soaked in hot water until both flavor agents and caffeine have been soaked out of them; 2) they are removed from the water, and the caffeine is removed from the hot water, leaving the flavor agents behind in the water; 3) the beans are then recombined with the water, where they reabsorb the now caffeine-free flavor agents. Once dried the beans are ready for sale and roasting.

The Sparkling Water Process (so-called because it uses water and Co2, the two components of sparkling water), soaks the caffeine out of the beans with compressed carbon dioxide, a ubiquitous and altogether harmless substance. Essentially, the carbon dioxide first selectively removes the caffeine from the beans, then water removes the caffeine from the C02, in a continuous cycle. Eventually the virtually caffeine-free beans are removed from the cycle, dried, and sent out into the world for roasting.

Taste, Roast, and Decaffeination
However powerfully it may affect our nervous systems, caffeine has very little effect on flavor. Isolated, it is a bitter, almost tasteless white powder. Coffee without it should taste virtually the same as coffee with it.

End of Chapter 4

Chapter 5 – Methods & Equipment
Despite the simplicity of the requirements, at this writing the home appliance world still has not given us an effective, inexpensive home roasting device. Consequently, most approaches described here are improvisations. They will produce excellent coffee, however.

The simplest approach of all is dumping the beans in a skillet and stirring them until they’re brown. This method does roast coffee, just as it did for hundreds of years before people started inventing machines to do it better. But the coffee produced by skillet-roasting surely will disappoint 20th-century sophisticates who have come to expect something tastier than the often scorched and uneven beans that satisfied our 18th-century forbears.

To save you the need to make notes, the important practical information contained in this chapter is summarized in the Quick Guide to Home Roasting Procedure.

Click above to purchase “Home Coffee Roasting”
Roasting Requirements
Let’s review what needs to take place in coffee roasting:
The beans must be subjected to temperatures between 460F and 530F (240C and 275C). These temperatures can be lower if the air around the beans is moving faster, as in fluid-bed roasting apparatus, or higher if the air is moving sluggishly;

The beans (or the air around them) must be kept moving to avoid uneven roasting or scorching;

The roasting must be stopped at the right moment and the beans cooled promptly. (Some provision must be made to vent the roasting smoke.)

Roasting with Hot-Air Corn Poppers
Both hot-air corn poppers produce a very consistent, uniform roast with bright acidity, good aroma, and a clean taste. The body may be slightly lighter than in coffees roasted by other methods, and the taste perhaps less complex.

Use only poppers that introduce the hot air from the sides of the popping/roasting chamber. Do not use designs in which the hot air issues from grill-covered openings or slots on the bottom of the popping/roasting chamber. With such styles it is possible that roasting chaff could collect around the heating elements, and eventually cause the device to ignite.

Hot-air poppers can be easily modified to incorporate a metal candy/deep-fry thermometer. This simple (two-minute) modification enables you to monitor the progress of the roast by the inner temperature of the beans rather than their outer color or appearance. Kenneth Davids outlines the installation process in his book, Home Coffee Roasting: Romance & Revival.

Click here for detailed instructions for Hot-Air Corn Popper Roasting.

Roasting in a Gas Oven
Achieving an acceptable roast in a given gas oven usually requires patient experiment with that particular appliance. Nevertheless, the flexible, precise control of temperature provided by gas ovens is an advantage, as are the venting arrangements, which carry the roasting smoke outside, usually with considerable efficiency. Most gas ovens will roast a pound or more of coffee at a time, and again, the flavor of oven-roasted coffee can be startlingly good.

Click here for detailed instructions for Gas Oven Roasting.

Style or Color of Roast
The simplest way to translate your personal taste in roast into home practice is to find a store that sells a whole-bean coffee roasted in a style you like, buy some, and attempt to duplicate it at home.

Click here for more information on Roasting Styles.

Timing the Roast
Coffee roasting is considerably more forgiving in this respect than many kitchen procedures. With fresh pasta, for example, a thirty-second distraction can turn al dente into al mush, whereas with coffee roasting a minute or two delay merely produces a darker roast that is still drinkable and enjoyable.

You need to learn to read the roast with “your senses,” as most roasters have done throughout history. The principles are simple: look, smell and listen. You need sample beans, already roasted to the color you prefer, to which you compare the color of your own beans as they roast and gradually deepen in color. Place these sample beans where you can see them easily during the roasting session.

After you begin the roasting process nothing dramatic will happen for some three to ten minutes while a grassy or burlap-like odor rises from the beans. There is no need to watch the beans during this early stage of the roast, but if you do you will notice that they are changing in color from a grey-green to a light, golden brown.

Eventually steam, still smelling like grass or burlap, will begin rising from the beans. Gradually this steam will darken and take on a coffee-like odor. On the heels of the appearance of the darker, coffee-smelling roasting smoke you will hear a subdued crackling sound, confirming the onset of pyrolysis, or the inner transformation of the bean.

From this moment forward you must depend mainly on sight. Assuming your goal is a medium to medium-dark (full-city) roast, wait about thirty seconds (hot air popper) to two minutes (gas oven) after the crackling sets in and begin peeking at the beans to monitor their color. How soon after the onset of pyrolysis you need to start your visual inspection of the beans depends partly on how dark you want to roast. Roasts develop rather quickly in hot-air corn poppers, later in gas oven roasting.

Regardless of whether you are pursuing a lighter or darker roast you will need to visually observe the beans as they approach the critical moment when they match the color of your sample. When they are about the same or a little lighter than your sample you must stop the roast and begin the cooling process, usually by dumping the roasting beans into a colander or bowl. I realize that “the same or a little lighter” is hardly precise language, but you’ll learn.

Never abandon roasting beans. This is a particularly important caution with hot-air popper methods. You should not even leave the room until the heat is off and the session over. If coffee beans are abandoned inside a hot roasting chamber long enough they become semi-flammable.

The gas oven method allows you a bit more leeway. By controlling the variables and keeping a few simple records, it is possible to determine approximately when to end a roasting session by elapsed time, thus permitting the use of a kitchen timer to alert you to the impending moment of truth.

Concluding and Cooling the Roast
Cooling the hot beans rapidly and efficiently is one of the most important steps in home roasting, since coffee continues to roast from its own internal heat long after it has been removed from external heat. Coffee that is allowed to coast down to room temperature of its own accord will taste dramatically inferior to coffee that is promptly and decisively cooled.

Many home roasters prepare small batches of a few ounces of beans per session, so simply dumping the beans into a colander and stirring or tossing them is sufficient cooling procedure. This procedure needs to take place over a sink or out-of-doors, so that the roasting chaff that floats free of the beans will not litter the counter or stove-top.

You also can initiate the cooling process by water-quenching, just as professional roasters often do. A pump or trigger spray dispenser, the kind with a nozzle that adjusts to a fine mist, works very well. Simply fill the dispenser with distilled or filtered water, and while stirring or tossing the hot beans subject them to a few seconds of light, intermittent mist. Perform this procedure immediately after roasting, and be careful not to overdo the application of water by spraying too long or using too coarse a spray.

Getting Out the Chaff
Removing the chaff using the hot air popper is no problem because the moving air removes the chaff during the roasting process. In other methods, tossing or stirring the beans in a large colander facilitates cooling, and rids the beans of most of their chaff. Any amount that is left in the beans will have little to no effect on flavor. The single most important piece of advice to home roasters in regard to chaff is not to be obsessive about it.

Two Ways of Looking at Roasting Smoke
The good news is that roasting smoke smells wonderful while you’re roasting. To some people it still smells wonderful two hours later, but to many of us it becomes stale and cloying.

Hot-air poppers can be used on a porch or balcony in clement weather, or operated directly under a kitchen exhaust fan. Don’t try to use them outside in temperatures under 50F however, since the cold may prevent them from achieving effective roast temperatures. Ovens that are components of kitchen ranges are well-vented and carry the smoke outside.

Those who like light-to-medium roast styles will have less to be concerned about than those who prefer darker roasts, since beans produce their most voluminous and intense smoke as they are carried to darker styles.

Accommodations for Differences Among Green Coffees
All coffees roast somewhat differently. If you have been roasting one coffee regularly and you begin roasting another, do not expect it to behave exactly like the first. For example, decaffeinated beans roast dramatically (15% to 25%) faster than non-treated beans, and must be observed with great care after pyrolysis sets in to avoid over-roasting.

Roasting Blends of Beans from Different Origins
The separate batches of beans from differing origins that together make upmost blends can be combined before or after roasting. If the batches are combined before roasting the look of the roast may not be absolutely uniform, but the cup quality usually will be fine. The only situation in which two components must be roasted separately is in the case of blends of decaffeinated and regular beans, since decaffeinated beans roast much more quickly than untreated beans.

Systematic Roasting: Controlling Variables
Some home roasters enjoy improvising; some relish the challenge of system and precision. A methodical approach is definitely the best way to achieve intimate knowledge of roast and coffee taste.

Informative experiment depends on control of four roasting variables:

the amount of coffee roasted;

the temperature inside the roasting chamber;

the identity of the green coffee (in particular its approximate moisture content, largely a condition of age);

the time or length of the roast.
This list of variables assumes that you are using the same roasting method or technology (i.e. gas oven, hot-air corn popper, etc.) for all of your experiments. The taste of a given roast style gotten by different methods will vary, sometimes greatly.

Like any good investigator, you need to control three of the four variables while systematically varying the fourth, meanwhile keeping careful record of the results. A sample form for recording notes on your roasting experiments is included in Home Coffee Roasting: Romance & Revival.

The two variables that you are most likely to experiment with are the identity of the green coffee and the length of time the roast is sustained.

Record-Keeping
If you are consistent from session to session with roast-chamber temperature, quantity of coffee roasted and quench method you can obtain useful results by recording only five to six variables: the identity of the green coffee, the date of the roast, the final bean temperature (if your method permits), the elapsed time of the roast, the appearance of the roasted beans, and your tasting notes.

End of Chapter 5

Quick Guide to Home Roasting
Outlined below are instructions for two home roasting methods:

Using a Hot-Air Corn Popper

Using a Gas Oven
Kenneth Davids covers other home coffee roasting methods in his book, Home Coffee Roasting: Romance & Revival including: Stove-Top Roasting with a Crank-Type Corn Popper; Roasting in a Convection Oven; and Roasting in ovens Combining Conventional and Convection Functions.

Click above to purchase “Home Coffee Roasting”
Roasting with Recommended Designs
of Hot-Air Corn Popper
Advantages
Somewhat simpler than other methods. Roasting temperature, for example, is already established.

Produces more consistent and uniform roast than other methods.

Disadvantages
Only units with recommended popping chamber design should be used to roast coffee. Other designs are potentially dangerous when employed for that purpose.

Roasts considerably less coffee per session than stove-top and oven methods.

Roasting smoke tends to be more difficult to control and vent than with oven methods.

Regular use to achieve very dark roasts (black-brown and shiny with oil, common names Italian or dark French) will shorten life of popper. However, can be used to produce moderately-dark to dark roasts usually called French or espresso.

Taste Notes
Hot-air poppers roast relatively quickly, thereby emphasizing bright, acidy notes in medium roasts and pungency in dark roasts. Taste tends to be clean and straightforward compared to more complex taste of beans roasted in gas oven or stove-top corn popper.

What You Need
Hot-air popper of recommended design only. Other designs may be dangerous when used to roast coffee.

Large bowl to collect chaff.

Sample beans roasted to style you prefer.

Green beans (same volume per session as volume of popping corn recommended by manufacturer of popper, usually about 4 fluid ounces or 1/2 cup).

Colander for cooling, large enough to accommodate about twice volume of green beans you intend to roast.

2 oven mitts or pot holders.

Procedure
Position popper under kitchen exhaust fan or near open window to dissipate roasting smoke. Can by positioned out-of-doors, but only in clement weather; low ambient temperatures (under 50F) may prevent coffee from roasting properly.

Place in popping chamber same volume of green beans as volume of popping corn recommended in instructions accompanying popper. Do not exceed this volume.

Make certain plastic chute (hood-like component above popping chamber) and butter cup are in place. Do not operate without chute and butter cup; they assist in maintaining proper temperature in popping/roasting chamber.

Place large bowl under chute opening to catch chaff.

Place sample roasted beans where they can be easily seen for color comparison to beans inside popper. Make certain cooling colander and oven mitts are at hand. If you wish to accelerate cooling of beans by water-quenching have pump spray bottle ready.

Plug in or turn on popper.

In approximately 3-4 minutes dark, coffee-smelling smoke will appear and beans will begin to crackle. Turn on kitchen exhaust fan if indoors.

About 1 minute (for light to medium roasts) to 3 minutes (for moderately dark to dark roasts) after smoke appears and crackling sets in, begin checking color of beans by lifting out butter cup with oven mitt and peeking into popping chamber.

Continue checking color of roasting beans against color of sample beans at 30-second to 1-minute intervals.

Roast develops relatively quickly with hot air poppers: typically 5-6 minutes to medium roast, 7-8 minutes to medium-dark, 9 to dark.

When roasting beans are same or slightly lighter color than sample beans unplug or turn off popper and using oven mitts, immediately lift popper and pour beans out of popping chamber through chute opening into cooling colander.

Carry colander outside or place under kitchen exhaust fan and stir or toss beans until warm to touch. To accelerate cooling, water-quench.

Problems and Refinements
Hot-air poppers can be easily fitted with metal candy thermometers to monitor approximate inner temperature of roasting beans. This modification permits the use approximate internal temperature of beans to determine when to conclude roasting session. Kenneth Davids outlines this process in his book, Home Coffee Roasting: Romance & Revival.

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Roasting in a Gas Oven
Advantages
Temperature in roasting chamber (i.e. oven) is easily controlled and repeatable.

With most gas ovens roasting smoke is effectively vented.

More coffee can be roasted in given session than with other methods.

Control over temperature enables those who experiment to roughly compensate for differences in density of green beans and broadly influence taste of roast.

Disadvantages
Hot spots inside some ovens and lack of strong convection currents may cause beans to roast unevenly: some beans lighter, some darker, some between. Solutions to this problem may require patience and experiment.

Timing roast can be difficult because color of beans may not be uniform and beans may be difficult to see inside oven.

Precision in roast style may be difficult to attain owing to uneven roasting.

Taste Notes
Somewhat uneven roast brings out complexity and depth of taste, since a range of roast styles may be present simultaneously in any given sample of beans. Gas-oven roasting probably produces best results for those who like medium-dark (full-city) through moderately dark (espresso) styles. It probably should be avoided by those who prefer either light or very dark roasts.

What You Need
Ordinary kitchen gas oven. (Do not attempt to use microwave ovens for coffee roasting. Conventional electric kitchen ovens can be used following these instructions, but typically produce roasts too uneven for most tastes.

One or more flat, perforated pans with raised edges. Palani Plantation produces inexpensive foil pans especially designed for oven coffee roasting. Some baking pans designed to crisp bottom crusts of breads or pizzas also work well. Perforations should be relatively close together (no more than 1/8″ apart) and small enough to prevent coffee beans from falling through (maximum about 3/16″ diameter). Pan should have raised lip around edges.

Sample beans roasted to style you prefer.

Enough green beans to uniformly cover surface of baking pan(s) 1 bean deep.

Colander for cooling, large enough to accommodate about twice volume of green beans you intend to roast.

2 oven mitts or pot holders.

Flashlight (necessary only if interior of oven is not illuminated and remains dark when you peer through window or crack open door).

Procedure
Virtually all gas ovens will produce a reasonably consistent and very flavorful roast, but success may require patience and experiment. If your first roast emerges uneven in color, don’t give up.

For Palani Plantation pan: Follow instructions accompanying pan. Preheat oven to 425F to 450F. For brighter, more acidy taste in medium roasts and more pungency in dark roasts try upper range of temperature; for more body and less acidity/pungency use lower end of range.

Preheat oven to 500F/260C to 540F/280C depending on condition of green coffee and desired taste characteristics. For brighter, more acidy taste in medium roasts and more pungency in dark roasts try upper range of temperature; for more body and less acidity/pungency use lower end of range.

Spread green beans closely together, one bean deep (no deeper) across entire perforated surface of baking pan. Pat beans down with flattened hand until they are densely but evenly distributed, touching or almost touching, but not piled atop one another. Make certain all of pan is covered with single layer of beans.

Place baking pan charged with beans on middle shelf of preheated oven.

Place sample roasted beans where they can be easily seen for color comparison to beans inside oven. Make certain cooling colander and oven mitts are at hand. If you wish to accelerate cooling of beans by water-quenching have pump spray bottle ready.

In about 7 to 10 minutes you should hear crackling from inside oven and smell coffee-like scent of roasting smoke.

About 2 minutes after crackling begins (for lighter roasts) to 3 minutes after crackling begins (for darker roasts) peek inside oven, with flashlight if necessary. If oven has no window, crack open oven door only as long as it takes to compare color of beans inside oven to sample of roasted beans.

Continue peeking at about 1 minute intervals, making comparison to sample beans. When average color of roasting beans is approximately same as sample, pull baking pans out of oven using oven mitts and dump beans into colander.

Over sink or out-of-doors, stir or toss beans in colander until cool enough to touch and until most loose roasting chaff has floated free. To accelerate cooling, water-quench.

Problems and Refinements
Actual temperatures in ovens may differ from control settings. Compare the actual temperature as indicated by an oven thermometer to control settings before first roasting session. Compensate for any difference when setting temperatures thereafter.

Beans always will roast somewhat unevenly. Nevertheless, they may taste as good as or better than uniformly roasted beans. Try them. If you don’t like flavor complexity, or if range between dark and light beans is too great (if darkest beans are almost black and lightest beans medium-brown, for example), one or more of following adjustments may be needed:

Make certain beans are uniformly spread one bean deep but no more over entire surface of pan.

Use middle shelf of oven. If results on middle shelf are unsatisfactory, experiment with higher or lower placement.

Place one or more cookie sheets on lower shelf of oven to break up flow of hot air through oven and thus dissipate “hot spots.” Arrange pans charged with coffee beans on upper shelf above cookie sheets. Situate cookie sheets in relation to bean-charged pans so as to break up pattern of hot spots revealed by previous roast sessions. In other words, if beans in middle of roasting pan emerge darker than beans at sides, position cookie sheet directly below roasting pan. If darker beans are at back of pan, position cookie sheet somewhat farther back in oven than roasting pan, etc.

If beans take longer than 15 minutes to reach a medium roast or 20 minutes to reach a moderately dark (espresso) roast, or if they taste bland or flat, start with higher temperature on subsequent sessions.

Keep records of oven settings and elapsed time of roasts while roasting same amount of similar green beans. When you achieve a roast you enjoy use same oven setting and set kitchen timer for 2 minutes or so before termination of roast. You still must make final decision when to stop roast based on visual observation.

After-Roast Resting
Freshly-roasted beans are at their best anywhere from four hours to a day after roasting. Coffee fresh out of the roaster is still superb, however, so don’t deprive yourself of enjoying it owing to gourmet obsessiveness.

End of Quick Guide to Home Roasting Procedure