How to Use This Book
The Many Waves of Coffee
Specialty Coffee versus Craft Coffee
CHAPTER 1: Brewing Basics
Strength and Yield
Brew Ratio and Dose
Grind Size and Contact Time
Dialing It In
CHAPTER 2: Choosing Hardware
Full-Immersion versus Pour-Over Brewing Devices
How Do Filters Factor In?
Kettles and Thermometers
Brewing Vessels, Servers, and Thermoses
CHAPTER 3: The Coffee
Varietals and Cultivars
CHAPTER 4: Buying the Coffee
Where to Find Craft Coffee
Deciphering the Coffee Bag Label
CHAPTER 5: The Flavor
Acids and (Perceived) Acidity
How to Assess Flavor
CHAPTER 6: Brewing Methods
The French Press (Press Pot, Coffee Press, or Cafetière)
The Abid Clever
The Siphon (Vacuum Pot)
The Kalita Wave
The Hario V60
APPENDIX: Troubleshooting, Tips, and Tricks
ABOUT THE AUTHORS
CRAFT COFFEE CAN BE A POLARIZING SUBJECT. In the United States, coffee has had a long history of being made poorly and conveniently—and bought and sold cheaply. For many colonial settlers, coffee was liquid fuel, something that got their gears going in the morning and made them forget, if only for a moment, that they were slowly and murderously humping (European) humanity westward. It wasn’t supposed to taste good, and for a while in the 19th century, it couldn’t taste good; there were no adequate tools. People would burn coffee beans in a frying pan and then boil them with water (enter sugar and cream). In the later part of the 1800s, manufacturers started making fake coffee from various grains, which people continued to buy, despite being aware of the con, until they realized the additives usually included actual poisons, like arsenic and lead. Later came convenient preground coffee and later still, because ground coffee goes stale quickly, vacuum seals, both of which were, more or less, marketing gimmicks. The expectation that coffee is gross, convenient, and cheap is deeply engrained in the American psyche, and some people get prickly when others start talking about good-tasting, mildly inconvenient, relatively expensive coffee.
Let them prickle. Read this book. Make great coffee.
My coffee journey did not start out as a deliberate quest for the perfect cup. Instead, I found my way to craft coffee via a circuitous road largely paved with ignorance and pragmatism. My parents never drank coffee, and I had little exposure to it growing up. In high school, I ordered my first cup of coffee black—at a local diner—because I didn’t understand that many people expect coffee to be vile and rely on cream and sugar to help them suffer through it. I accepted the thin, bitter brew without question. I had become a black-coffee drinker. Without the sweet embrace of cream and sugar, it didn’t take me long to realize that different coffees have different tastes. I knew that diner coffee was markedly different from Starbucks coffee, and Starbucks coffee was distinct from my local independent café’s coffee—but I never thought to ask why.
I also never lived near a café that offered manually brewed coffee—I didn’t even know such cafés existed or that manual brewing methods had qualitative differences from machines. When I purchased my first pour-over device in graduate school, it was only because a machine seemed extravagant and unnecessary for the single cup I brewed each morning. I figured out how to work it well enough, but only occasionally did I brew significantly better coffee than that diner back in high school did. Then one day my friend Andreas (who is now my husband) came over and saw I had a manual coffeemaker. He happened to be a barista and seeing that I had never invested any time in learning how to use the device properly, he showed me a couple of easy ways to improve my brew. As it turns out, coffee—when brewed manually—can be controlled and even manipulated for best results every time. For me, this was a revelation.
By the time Andreas and I moved to Chicago after graduate school, independent roasters and cafés had been thriving for years, and it was easy to sample coffee made with high-quality beans from around the globe and brewed on any of several different devices. This coffee was flavorful, smooth, and full—a far cry from my first black cup.
Most people recognize that diner coffee often leaves much to be desired and turn to chains like Starbucks and Peet’s for better alternatives. For many people, their first exposure to smooth, flavorful, high-quality coffee takes place at a small independent café. They then try to make the same coffee at home, but somehow, it never tastes as good as it does at the café. From there, it’s hard to know where to turn. The internet, with its depths of overwhelming, conflicting information, can make it difficult for home coffee brewers to learn how to improve. Then there are baristas, who can cause a different kind of hesitation. The coffee world uses a lot of jargon, and as in any new community whose members talk to each other in code, it can be intimidating to approach a professional with questions—especially in the coffee industry with its unfortunate (although often undeserved) reputation for snobbery.
Today, many baristas are working to change this perception. Still, certain assumptions are often made in the professional coffee realm: this is the way coffee should taste, this is the way to make it, and this is the way to think about it. In reality, there is no one right way for any of it, and insisting that there is doesn’t do curious home brewers like us much good. We all appreciate good coffee, but we don’t have to appreciate it in the same way.
That being said, some professional brewing tactics may not be a good fit or even necessary for the home kitchen. Because we collectively know relatively little about why coffee does what it does on a scientific level, a lot of misinformation is out there—often in the form of techniques and practices that have little or no rationale behind them—and baristas aren’t necessarily immune to it.
This book is not written from the perspective of a coffee professional. It’s written from my perspective, as a coffee lover and home coffee brewer who has heard it all from the coffee professional who lives with me. I don’t make assumptions about your coffee knowledge, budget, or level of fervor. Instead, I realize that coffee enthusiasts exist on a spectrum, and that you will need to (1) figure out where you fall on the spectrum and (2) make coffee decisions that reflect that. This book explores the full body of coffee knowledge and offers guidance, perspective, practical advice, and a healthy dose of my own (informed) opinion to help you make those decisions and develop your own preferences. My goal is to provide you with at least the baseline of knowledge you will need to forge a path toward your own perfect, delicious cup. Take what you want and leave the rest.
HOW TO USE THIS BOOK
This book is organized a bit differently than other coffee books. Chapter 1 contains what I consider to be the most important information when it comes to improving your brew at home: a solid grasp of the science of extraction and the factors that affect it. Understanding why coffee behaves the way it does means that when it comes time to brew, you will know how to troubleshoot less-than-stellar cups and replicate desired results day after day. You can manipulate the fundamentals of brewing coffee depending on what equipment, brewing device, and beans you decide to use, which is why I think you need to read about those fundamentals before you ever pour water over grounds. This is a book about making coffee, after all, and there’s no reason to get distracted by how beans grow until you understand the basics of brewing.
Chapter 2 is all about guiding you toward the coffee equipment that is right for you. Like any hobby, coffee making requires a certain amount of gear. The coffee industry loves gear—new devices and contraptions hit the market all the time. Are they all necessary? No. The reality is you will likely brew on only one device (even if, like me, you own a dozen), which is why it’s crucial that you purchase the device that best suits your lifestyle, taste preferences, and budget.
Not all brewing devices work the same way or produce the same coffee, however; each one brings pros and cons to the table, including how they affect the qualities of the cup. This chapter outlines the two major methods of brewing (pour over and full immersion) as well as 10 different manual brewing devices, paying particular attention to the factors you will likely care about the most when selecting your device: how easy it is to use, how easy it is to find, and how much money it costs. Brewing devices, however, don’t exist in a vacuum. To properly brew café-quality coffee at home, you also must consider the other equipment involved—such as filters, grinders, scales, and kettles—that may or may not be required to optimally brew on a certain device and/or achieve your coffee preferences. Chapter 2 assesses those gadgets as well.
Only after you have selected your device and other coffee hardware should you start thinking about beans. Chapter 3 explores the complex world of high-quality coffee beans, which can taste quite different from each other depending on what kind of coffee they are, where they were grown, how they were processed, and how they were roasted. In my experience, the knowledge gap between coffee professionals and enthusiasts is often widest with regard to the beans, so this chapter tells you what you need to know and builds your bean vocabulary. Once you have an idea of what kinds of beans you might like, chapter 4 takes things a step further by explaining how to actually find and purchase high-quality beans, which can be a challenge if you don’t know where to look or what to look for. When you finally get your hands on a bag, deciphering the label ushers in a new set of challenges, so this chapter ends with a section that teaches you how to decode coffee-bag jargon as well as how to store your carefully selected coffee once you get it home.
Next, I talk about coffee’s flavors and how to develop your palate in chapter 5. I view the information in this chapter as bonus knowledge. You will know whether or not you like a cup of coffee simply by tasting it—it doesn’t matter whether or not you understand why. But, developing a knowledge of coffee flavor and how it works can help you better identify the coffee you are most likely to enjoy and communicate your preferences to others, which can be fun. It also gives you a sense of what you should be looking for flavorwise before you starting brewing and evaluating cups at home.
Once you have your device, your coffee, and a grasp of what you like, you are ready to brew! The last chapter provides kitchen-tested instructions and specifications for the 10 brewing devices outlined in chapter 2. Some devices have multiple methods, and each method is labeled with icons that show what type of additional equipment I recommend for best results with that method. With your newfound coffee knowledge, you’ll be on your way to making consistent, replicable results every morning.
Throughout the book, I have also provided tips and tests designed to help you troubleshoot your cup, but to make things even easier, I have included an appendix at the end that outlines common coffee-making mistakes and how to correct them for your next brew.
Where’s the Espresso?
Most coffee books have sections on espresso and milk. I have deliberately excluded that discussion from these pages. Why? Well, the point of this book is to show that ordinary people can make extraordinary coffee at home, no matter their budget, skill set, or level of enthusiasm. I just don’t think you can make extraordinary espresso at home without expensive equipment. Even the $500 espresso machine models you can get online don’t really cut it, and professional-grade machines are well out of reach of most people’s pocketbooks. Espresso machines are also more vulnerable to scale, so if you don’t have some kind of pricey filtration system, you are either going to ruin your machine, make bad espresso, or both. Lastly, great espresso is all about fine-tuning. Tiny differences can make or break a shot. Professional shops fine-tune their shots throughout the day, and it doesn’t seem practical for someone at home to pull a bunch of shots each morning until they get it right. Besides, this book has a lot of words in it already.
THE MANY WAVES OF COFFEE
According to a 2014 report by the National Coffee Association, a whopping 61 percent of Americans drink coffee on a daily basis. Though we may not always think of it this way, coffee is woven throughout much of the United States’s history. It likely played at least a small part in colonial life since the earliest days of British settlement, as England had been introduced to coffee in the 16th century. But the beverage didn’t become popular until the Boston Tea Party in 1773, when politics encouraged our citizens to turn their backs on Earl Grey and fall into the arms of coffee. Eighty-eight years later, the New York Times reported on a similar proposed tax, this time on coffee imports, designed to fund war efforts, saying, “All patriotic citizens feel that it is a sacred duty to support the Government in this trying hour, and to submit to any sacrifices that may be necessary to maintain the integrity of the Union.” By that point, the United States was already consuming more coffee than any other nation—a quarter of the world’s production, according to that same article.
Industry professionals often describe the history of US coffee consumption in three waves. The first wave of coffee started in the 1800s, when global coffee consumption exploded and big coffee outfits like Maxwell House, Hills Bros., and Folgers started growing to prominence—at least here in the United States. In general, market share—driven by speed, convenience, and caffeine—was more important than quality during this period. For the most part, these companies sold commodity coffee, that is, coffee that is bought and sold on commodity markets, as wheat, sugar, and other standardized “soft commodities” are. One way this is done is through futures on exchanges, such as the New York Mercantile Exchange and the Intercontinental Exchange. Commodity coffee, both then and now, involved a complicated web of exporters, importers, investors, buyers, and sellers, as well as prices that were subject to huge variations for a number of reasons, including those related to politics, weather, and speculation. The commodity coffee sold to the masses was not (and is not) always of the highest quality, but for much of coffee’s history in the United States, quality considerations were, frankly, beside the point.
Eventually, enough people decided that the mass coffee product available to consumers did not pass muster. Growing antipathy toward low-quality coffee inspired the second wave of coffee, led by companies, such as Peet’s Coffee & Tea and Starbucks, that valued something new: quality and community. To give you a sense of the timeline, Peet’s opened its first store in 1966 in Berkeley, California; Starbucks opened its first store in 1971 in Seattle, Washington; and in 1978, the legendary Erna Knutsen—a secretary turned coffee broker who specialized in selling high-quality beans from specific origins to independent roasters—coined the term specialty coffee to better communicate the goal of her trade: to recognize the special qualities of individual beans. Achieving this goal required placing new emphasis on proper processing, roasting, and preparation—that’s specialty coffee in a nutshell.
From there, the philosophy and language of specialty coffee grew increasingly popular. In 1982, the Specialty Coffee Association of America (now known simply as the Specialty Coffee Association) was founded to help set standards for this burgeoning industry and to help its members communicate, innovate, and grow and market high-quality coffee to consumers. Along the way, specialty coffee establishments sold the idea and the experience of specialty coffee to a demographic—a large one, as it turns out—that was willing to pay a premium for it. Between 1987 and 2007, Starbucks opened an average of two new locations a day.
Significantly, specialty coffee has changed the way some coffee is bought and sold. A sizable portion of specialty coffee isn’t sold or traded on commodity markets. Instead, large specialty coffee companies often contract directly with producers, and smaller roasters sometimes use importers that specialize in sourcing the highest-quality beans available. Specialty coffee shops are extremely popular (recent research estimates that there are more than 31,000 specialty cafés in the United States today compared with 1,650 in 1991), and from a consumer perspective, the beloved coffee-shop experience has arguably played a significant role in this growth. But somewhere along the way, the importance of the experience of specialty coffee had started, to some, to supersede the importance of quality.
So perhaps it comes as no surprise that many in the industry say we are currently living in the third wave of coffee. The term, first coined in 2002 by Trish Rothgeb of Wrecking Ball Coffee Roasters, generally refers to the growing number of importers, roasters, and baristas who, above all, treat the coffee bean as an artisanal food product, much as people do with cheese, wine, and (more recently) beer. In order to fulfill that mission, third-wave coffee professionals often adopt certain philosophies. They champion the unique qualities of individual beans, which, among other things, have led to new roasting techniques that leave beans distinctly lighter than more traditional roasting methods do—probably the most readily recognizable difference between second- and third-wave coffee for consumers. Additionally, there has been a growing emphasis on education and quality improvement. This has generated new research, programs, and certifications for people at all stages of the coffee trade—from producers to roasters to baristas—with the goal of sharing knowledge and techniques that benefit each step of the coffee-making process. Most third-wave professionals are also interested in ethics and transparency and strive to work fairly with producers, who have routinely gotten the short end of the stick. The third wave aims to show coffee producers proper respect for their work, both through fair compensation and in the way their coffee is presented to consumers.
Coffee Jargon, Motherf***er, Do You Speak It?
Coffee consumers like us have had about 40 years to get used to the language and style of second-wave specialty coffee, particularly those of the biggest chains. Starbucks, for example, was in full swing before I was even a glint in my mother’s eye. We know specialty coffee. It’s ubiquitous. Its caffeine has coursed through our veins. Its aftertaste lingers on our tongues. But the language and style of third-wave coffee is brand-spanking new—at least to the masses, who are becoming increasingly interested as third-wave operations continue to expand and second-wave chains adopt third-wave practices. Now there’s an entire new set of techniques and words to understand, and coffee professionals do not always do the best job of communicating those with us. This element of mystery can make us feel tension and fear. Wanting to ease that tension and fear is one of the reasons I wrote this book. Coffee should not be mysterious.
SPECIALTY COFFEE VERSUS CRAFT COFFEE
Industry professionals and trade organizations use the term specialty coffee to distinguish coffee that meets their high standards from the majority of coffee found in the commodity trade. Likewise, they use the term third wave to distinguish specifically the latest generation of coffee, with its new emphasis on craft and ethics, from the overarching umbrella of specialty coffee. In other words, second-wave and third-wave coffee are both specialty coffee; their ideologies are just a bit different.
That being said, I am deliberately choosing not to use the term third wave in this book, even though the movement and I appear to have the same goals in mind. For one thing, it isn’t very descriptive; third wave doesn’t capture the defining characteristics of the movement and is, in some ways, inaccurate. For another thing, the media have all but turned the term into a pejorative, using it to remind us that a bunch of millennial hipsters are drinking fancy, fussy, overpriced coffee and trying to make something simple into something complicated for unfathomable, pretentious reasons. But making coffee a tiny bit more complicated can be a good thing. Let me explain.
In terms of ingredients, of course, coffee could hardly be simpler. But the coffee bean itself is incredibly complex, made up of thousands of compounds, most of which we don’t fully understand—at least not on a scientific level. Archeological evidence suggests that humans have been making wine for about 8,000 years and brewing beer for about 7,000 years. Coffee, on the other hand, likely wasn’t extracted and consumed until the 15th century, which means that compared with wine and beer, coffee lacks at least 6,000 to 7,000 years’ worth of human knowledge and refinement. Making coffee, let alone making good coffee, is still a relatively new concept. Best practices for farming and processing coffee, for example, are still being developed all the time. The art of roasting—how roasters strategically manipulate coffee’s compounds to unlock flavor—is in its infancy, as is our progress toward perfecting our brewing methods, the ways in which we extract flavor from coffee beans.
Despite being works in progress, all of these efforts to improve (and thus further complicate) coffee have already proven effective: coffee has never in the history of humankind tasted better than it does right now—and people are noticing. Today, the number of people interested in good coffee has reached a critical mass, one that has spawned hundreds of think pieces and spurred the second-wave Big Boys to make significant investments in the so-called third wave, whether they are buying up influential companies like Chicago’s Intelligentsia or creating an ethos like Starbucks seems to be doing with its cold brew, its cascara syrup, and its Reserve shops. Many people still say there’s no reason for coffee to taste good, but an increasing number of people (including you, probably, and me) say there’s no reason for coffee to taste bad.
Having said that, it takes skill to make coffee taste good—skill on the part of the farmer, skill on the part of the processor, skill on the part of the roaster, and skill on the part of the coffee maker. Farming, processing, roasting, brewing: these are all, to some degree, manual skills that involve study or apprenticeship—a craft. This book focuses on the last part, brewing, which is among the most manual of skills—you are learning to brew coffee literally by hand as opposed to with a machine.
This is all a long-winded way of saying: I believe coffee is a craft and coffee professionals and enthusiasts are craftspeople. That’s why I have taken to calling what is essentially third-wave coffee craft coffee instead. It is more descriptive; it makes more sense. The word craft implies a degree of skill and study—manual skill and manual study, at that. It also implies something small. Craft coffee’s slice of the pie may be relatively significant—significant enough for coffee behemoths to suspect that they are missing out on a piece of the market—but it is still operating on a tiny scale. All craft coffee is specialty coffee, but not all specialty coffee is craft coffee. Craft coffee beans account for only a fraction of the total number of coffee beans produced each year. They are roasted, for the most part, carefully and in small batches. And if you add up all of the cafés that the top four craft coffee companies own, you get—as of this writing—just 52! Starbucks alone has 25,085 locations.
Another reason I like the word craft is that it doesn’t imply, as third wave does, that contemporary coffee lovers discovered great coffee. It’s important to remember that the desire for quality coffee is not strictly a 21st-century phenomenon. For as long as there has been coffee, there have been people humbly trying to improve their home brew and unlock the mysteries of the bean. In the past, those people probably felt as though they were merely shouting into the void (imagine trying to explain the science of extraction to cowboys or gold prospectors who boiled their coffee in the same piece of cheesecloth until it fell apart), but today, we owe these problem solvers a great debt.
In 1922, one such problem solver, coffee enthusiast William H. Ukers, finally published his 700-page opus, All About Coffee, after having taken 17 years to write it. In it, he noted that while coffee preparation in the United States had certainly improved in general, he hoped that soon “it may be said truly that coffee making in America is a national honor and no longer the national disgrace that it was in the past.” It’s been 95 years, and here we are, hanging our hopes on the same hook. Let this book help you join Ukers’s league of problem solvers in whatever capacity you choose to participate.
BEFORE YOU CAN IMPROVE YOUR BREW, you must have an idea of what’s going on when water meets coffee. In this chapter, you may want to keep reminding yourself that coffee is simple—well, making it is simple, but the bean itself really isn’t. The more time you spend trying to understand the bean, the more complexity it reveals. It’s almost as if coffee beans do everything in their power to give you a hard time. They are, by nature, inconsistent, and if you want to optimize your cup, you must account for that irregularity. This chapter introduces you to coffee’s inconsistencies and, based on the best knowledge the industry and science have to offer, outlines how water and coffee interact to make our beloved beverage. It also describes how (and why) you can manipulate factors such as brew ratio, dose, and grind size to optimize your brew. With a solid understanding of these concepts, you can create the cup of coffee you want day after day. Along with helping you to troubleshoot less-than-ideal cups, understanding coffee at its most basic level will help you make more informed decisions about the devices and coffee that are best suited for your lifestyle and preferences.
Extraction is the process of pulling flavor and texture compounds—insoluble oils, soluble gases, insoluble solids, and soluble solids—from the coffee grounds into the brewed coffee. In other words, it’s what turns water into coffee. Obviously, you don’t need to know the science behind how and why extraction happens in order to make coffee—you can just let the water do its thing. However, a solid foundation of extraction knowledge comes in handy when you are deciding what you like in a cup of coffee and how to replicate it day after day. The decisions you make—the device, the filter, the method, etc.—will all affect how your coffee extracts, and it will be difficult to manipulate brewing factors later on if you don’t have a solid understanding of the basics. Let’s start by looking at a few broad categories of coffee compounds that, in a sense, come alive when introduced to water:
•Insoluble oils. These oils are present within coffee beans but do not dissolve in water. Insoluble oils tend to be more visible in cups of coffee made with devices that use metal filters; they are partially or almost entirely trapped by cloth and paper filters. Insoluble oils can influence how coffee feels in your mouth. For example, particularly oily cups are often described as “creamy” or “buttery.” If you look into almost any cup of coffee, especially if it’s been sitting for a bit, you can usually see a faintly iridescent oil spill floating on the coffee’s surface. That’s from the insoluble oils.
•Soluble gases. These are gases that dissolve in the brewing water during extraction. They are the main contributors to coffee’s aroma. For example, a cup of coffee might smell a bit like blueberries, or earthy, like hay. Different soluble gases are released at different temperatures, which is why you may notice that your coffee’s aroma changes as it cools. As you likely know, aroma and taste are closely linked. The changing aroma is one of the main reasons why coffee’s taste changes as it cools down.
•Insoluble solids. These are substances that do not dissolve in water, such as large protein molecules and tiny fragments of ground coffee beans (often called fines). Like insoluble oils, insoluble solids influence how coffee feels in your mouth and on your tongue. For example, a cup with lots of insoluble solids may feel kind of gritty. Many of the most popular brewing devices use filters to keep the majority of insoluble solids out of your cup.
•Soluble solids. These are substances that dissolve in the brewing water during extraction. They are particularly important because they determine how sweet, salty, bitter, sour, or savory the coffee will taste. In short, they largely determine a coffee’s flavor.
Water extracts these compounds from the coffee grounds, and heat speeds up the process (cold water can do it, too; it just takes much longer). It happens in three stages: First, the hot water rinses the grounds of any surface material and displaces carbon dioxide (a by-product of the roasting process), which is why your coffee bed appears to breathe (aka bloom) when you brew fresh coffee. The carbon dioxide creates a barrier between the grounds and the water, so it’s a good idea to wait until some of the gas dissipates before continuing your brew. Next, the soluble gases and soluble solids start dissolving in the hot water, creating that trademark coffee aroma and flavor. Finally, once these solubles are dissolved, osmosis pulls them away from the grounds.
These compounds don’t all dissolve at once, however: coffee contains many different soluble solids that dissolve at different rates and impart various flavors to your cup. Here are a few of the more important ones:
•Fruity acids. These are among the smallest flavor molecules and tend to dissolve first. They give fruity and floral aromas to the cup. As their name suggests, they provide perceived acidity to a cup of coffee, but in high concentrations, they can make the cup taste gross and sour.
•Maillard compounds. These guys are produced during the Maillard reaction part of the roasting process (see page 146). Hundreds of compounds are produced from the Maillard reaction, and science is still sorting out exactly how they influence flavor and aroma. Some scientists say Maillard compounds can provide everything from grainy, nutty, or malty flavors to smoky, meaty, or caramel flavors in your cup.
•Browning sugars/caramels. These molecules are also created during the roasting process as natural sugars in the beans are caramelized. Some experts say they help contribute to perceived sweetness in coffee. They take a bit longer to dissolve than fruity acids. As you’ll read later, the longer coffee is roasted, the more caramelized these sugars become. If roasting continues, the sugars can leave caramel country and enter carbonized territory—which means they are burning. Less-caramelized sugars (which taste sweeter) dissolve first, and highly caramelized sugars (which taste bittersweet) take longer to dissolve. This is part of the reason why darker roasts tend to be bitterer—there is less sweetness available to begin with. Sweetness in coffee often turns up as notes of chocolate, caramel, vanilla, or honey.
•Dry distillates. These are the molecules from the Maillard reaction and caramelization parts of the roasting process that lean more into burnt territory. They are more common in darker roasts, obviously, and impart tobacco, smoky, and carbon flavors. These molecules also tend to be bitter. These are the slowest molecules to dissolve, but they pack a punch. Even at low levels, they can mask the other flavors so that the entire cup just tastes bitter.
The goal of extraction is to achieve a balanced cup—that is, a cup in which the right amount of these dissolved compounds is present and contributing a pleasant mix of acidic, sweet, and bitter flavors. It’s odd, but none of these soluble solids tastes particularly great on its own (see the experiment on page 18). Striking the right balance is a strange and subtle alchemy, one that is directly linked to time. If your coffee grounds are not in contact with the water long enough, then many of the soluble solids, save for the fruity acids, will not get a chance to dissolve. Without other flavors to dilute the acidic qualities of the fruity acids and add complexity, your cup will likely taste sour, unpleasant, and/or dull. In other words, your coffee is not extracted enough; it’s underextracted. On the other hand, if your coffee grounds spend too much time with the water, you risk getting a higher concentration of dry distillates in your cup, which tend to overpower the other flavors with their bitterness. This is a cup that has extracted too much; it’s overextracted. Keep in mind that all of this can happen in a relatively short amount of time—30 extra seconds could be enough to damage your cup.
What is the most important criterion for determining how well your coffee extracted? Taste. I’m not trying to be flip—it’s just that the only thing that really matters in the end is how your coffee tastes, and it’s important to remember that, despite everything I’m about to tell you.
Fun Extraction Experiment
Want to better understand how different flavor molecules extract at different rates? You can! Try an experiment in which you brew 400 grams (about 1⅔ cups) of coffee in four phases with your favorite pour-over device. You will need a gram scale (or really sharp eyes), the correct dose of coffee for your device, and four different mugs set out and ready to go. Set up everything as you would for a regular brew (see page 51), but only brew 100 grams (about ¼ of the water) into the first mug (phase 1). Quickly remove everything from the scale, set the next mug on top, transfer the dripper, and tare, or zero, the scale. Brew the next 100 grams (phase 2). Repeat the process for phases 3 and 4 until each mug contains about 100 grams of coffee. Now it’s time to taste. Make sure to taste each sample in the order in which it was brewed and record your findings. How do the samples compare to one another? How does the phase 1 sample compare to the phase 4 sample? How does what you learned about extraction explain the differences in how the four samples taste? At the end, combine all four samples together into one mug. How does that taste? This experiment isn’t perfect, but it should illustrate the different stages of extraction well enough.
STRENGTH AND YIELD
When coffee professionals evaluate the quality of a cup, they look at two things: strength and yield. The measure of these two factors is a good indicator of whether a customer is going to find the cup pleasant or not. Like I said, your taste buds will tell you whether or not you like a particular coffee, even if you don’t realize they are responding to its strength and yield. But isn’t life easier when we can use our words?
Strength is an easy concept to understand: it’s the measure of the total dissolved coffee solids (TDCS)—another term for the soluble solids from the previous section—in a cup, usually presented as a percentage. If a cup is 1 percent TDCS, that means the other 99 percent is water. Strong cups contain more TDCS than weak cups.
“Strong coffee” is a familiar phrase that a lot of us use incorrectly. People often say “strong coffee” when they are referring to the flavor or the perceived caffeine content of a cup. Technically speaking, strength only refers to the body of the cup: how it feels in your mouth. A strong cup, one with a higher concentration of TDCS, might feel thick on your tongue. A weak cup, one with a lower concentration of TDCS, might feel closer to water, or thin. Whether you realize it or not, one of the ways your tongue decides whether you like a cup of coffee is by how it feels. If the coffee feels too thick or too insubstantial, you might be turned off. For more information on these distinctions, check out the Body section on page 191.
One weird thing about strength is that the difference between strong coffee and weak coffee is quite small in terms of the percentage of TDCS. For example, most people here in the United States would consider a cup that contains 1 percent TDCS and 99 percent water too weak and a cup that contains 2 percent TDCS and 98 percent water too strong. Most “good” cups of coffee fall somewhere between 1 and 2 percent TDCS, although it’s always up to personal preference.
The second part of evaluating extraction is yield (sometimes called extraction yield or solubles yield), and it’s a bit hairier to explain. Yield is a way to measure extraction, and it refers to the amount of material that the water has removed from the actual coffee grounds. Think of it like this: if you have a pile of coffee grounds, you are starting with 100 percent coffee material. The maximum amount of coffee material that is physically possible for hot water to remove (extract) is somewhere around 30 percent, and that would likely bear an utterly disgusting cup. Coffee professionals usually aim to extract somewhere between 18 and 22 percent of coffee material from the grounds.
Coffee that has a low yield (less than 18 percent of the coffee material has made its way into the cup) usually tastes underextracted, and coffee that has a high yield (more than 22 percent of the coffee material ends up in the cup) usually tastes overextracted. This all comes back to time: the longer that water and coffee mingle, the more opportunity there is for extraction.
Your tongue can tell if your cup is over- or underextracted. In general, underextracted coffees lack complexity (meaning you are unable to taste multiple distinct flavors in the cup) and are often sour. Their aromas are normally faint and/or simple, and their bodies are thin. Overextracted coffees are often overly bitter and astringent (drying), which hides the yummy flavors in the cup. Their bodies are usually thick and syrupy. The best cups tend to be somewhere between under- and overextracted and are more likely to offer a range of pleasing flavors.
The Coffee Brewing Control Chart
For you visual learners, the Coffee Brewing Control Chart can help you wrap your head around strength and yield, which can help you understand how to correct over- and underextracted coffee until it’s just right. How do coffee makers know what “just right” means? An MIT chemist named E. E. Lockhart developed the Coffee Brewing Control Chart in the 1950s to try to answer that question. He surveyed a bunch of US coffee drinkers about their preferences and found that most people prefer coffee that falls in the “ideal” square shown on the chart: an extraction yield between 18 and 22 percent and a strength measurement between about 1.15 and 1.35 percent. Lockhart’s original findings are still supported by the Specialty Coffee Association (SCA) today—although these general preferences can vary around the world. While it may seem counterintuitive, you’ll see that it is possible to brew a cup of strong, underextracted coffee and a cup of weak, overextracted coffee (actually, the latter describes typical diner coffee).
COFFEE BREWING CONTROL CHART
Brewing Ratio: Grams per Liter
There are ways to calculate strength and yield with special tools and math (as indicated by the numbers on the chart), and it’s tempting, even for professionals, to try this—but I’m not going to tell you how to do that here. It’s nice to be aware of the ranges described in the chart, but I can’t emphasize enough that you shouldn’t let numbers distract you from taste. There is a sentiment among some coffee professionals that measurements like these encourage folks to stamp a cup of coffee as “good” based on calculations rather than taste. However, numbers don’t tell the whole story—a bunch of different factors affect how coffee extracts, including the type of coffee, the processing method, and the roast. This means that even if two coffees have the same yield—20 percent, for example—they could still taste very different from each other.
The upshot of understanding how strength and yield work is that you will be able to experiment with both measures in your home brew. In order to do that most effectively, you’ll need to understand the different brew variables that affect strength and yield—brew ratio, grind size, contact time, water, and temperature. These are the building blocks of every coffee recipe.
BREW RATIO AND DOSE
If you’re going to make coffee, you need to know how much coffee and water to use. When I first started making coffee at home, I literally just guessed how much to use based on vague memories of what I had seen others do. If optimizing your cup is your goal, I don’t recommend this method. Instead, you should consider two things: (1) how much coffee you want to end up with and (2) your personal preferences for strong or weak coffee.
Your brew ratio—the amount of coffee to water you use—has a direct effect on the strength of your cup. Remember, strength refers to the concentration of coffee compounds present in the brew, which affects the mouthfeel of your coffee, or how it feels in your mouth. The more coffee to water you use, the stronger your coffee will be. The less coffee to water you use, the weaker your coffee will be. The more coffee you start with, the more compounds end up in your cup.
Brew Ratio and Taste
High brew ratio (too much coffee):
thick mouthfeel, muddled flavors, very aromatic
Low brew ratio (too little coffee):
thin mouthfeel, weak flavors, faint aroma
Lots of people will tell you that the correct brew ratio is two tablespoons of ground coffee for every six ounces of water. For his part, Beethoven reportedly counted out 60 whole beans for each cup of coffee he made. You can start with either of these tactics if that’s easiest for you, but I (and most professionals) use a slightly different method of measuring coffee because consistency—being able to replicate desired results—is key, and the methods described earlier are not consistent.
The two-tablespoons method requires ground coffee, and if you are using fresh whole beans, you won’t be able to measure until you grind them, which can be wasteful and expensive (high-quality beans aren’t cheap). Beethoven’s method removes the waste factor, but beans can vary greatly in size. Sixty beans from one type of coffee plant may end up providing significantly fewer grounds than 60 beans of another type of coffee plant. The solution? Use a brew ratio based on weight in grams.
Most coffee professionals in the United States use a brew ratio between 1:15 (that’s 1 gram of whole coffee beans to 15 grams of water) and 1:17 as a starting point. That will get you close to the “ideal” range on the Coffee Brewing Control Chart. Yes, this means measuring both beans and water by their weight, instead of by their volume, which is what you’re likely familiar with. Still, measuring both items with a single unit of measure means you can simplify this stage of the process by using only one piece of measuring equipment—an inexpensive kitchen scale.
How Much Does Accuracy Matter?
I know a lot of you will choose the two-tablespoons method, and that’s fine. But for next-level brewing, I highly recommend measuring by weight and using a brew ratio for three reasons:
•It’s more accurate.
•It makes it easier to troubleshoot/adjust your cup.
•It accounts for the variability in devices.
What some people may not realize is that the actual mass of the amount of coffee that fits inside a measuring spoon can vary greatly. Despite what you may have heard to the contrary, that’s not something coffee people have made up to be complicated; it’s science. It’s why experienced bakers tend to measure by weight. One cup of all-purpose flour might not be the exact equivalent of the next cup you measure; maybe you inadvertently packed the second cup more, meaning there was more mass in that cup than in the first. Even a bit too much flour in baking can lead to less-than-ideal results.
For coffee, there’s even more room for inconsistency. I already mentioned the fact that different coffee beans can vary significantly in size (just look carefully at your next bag of blended beans). This means the mass of one tablespoon of this bean might differ from the mass of one tablespoon of that bean. It’s like the difference in weight between one cup of all-purpose flour and one cup of whole-wheat flour. These masses can differ by a gram or more, which is significant when you are dealing with relatively small measurements. Additionally, if you are measuring coffee grounds, the grind size also comes into play. A tablespoon of finely ground coffee will certainly have a different mass from a tablespoon of coarsely ground coffee. When the difference between your perfect cup and a not-as-good cup can be half a gram or less, it’s critical to get exact measurements. The same is true for water—a tablespoon of water is supposed to weigh about 14.8 grams, but try weighing tablespoons of water and see how often that ends up being the case.
Measuring by weight, however unfamiliar, is the only way to ensure precise, consistent brew ratios and consistent cups. Otherwise, you may luck out with a delicious cup, but it will not be a result that’s easily replicated unless you record the ratio for future use. After all, coffee has only two ingredients—even small variations affect the taste. When you do something consistently, it makes it easier to know what to adjust, if need be. For example, if your coffee feels quite thick and overwhelming in your mouth (strong), you might be using too much coffee, and next time you can use less. If it feels too watery (weak), you might be using too little coffee, and next time you can use more.
Lastly, ideal brew ratios vary depending on the device you are using. As you’ll see in the next chapter, devices are specifically designed to optimize extraction, but their designers have different ideas about how to go about doing that. How your device works to extract coffee can certainly affect the brew ratio (or ratios) that tend to work best with it.
How to Calculate Dose
The amount of coffee that’s used in a brew ratio is called the dose. Calculating dose requires math. I hate math because in sixth grade I failed my advanced placement test, but my teachers decided to advance place me anyway, which prompted a six-year struggle through AP classes that I’m clearly not over yet. But even I can calculate dose. And the good news is that once you figure out your dose, you can use the same numbers over and over again without having to calculate anything! The other good news, which I mentioned before, is that my brew ratios let you measure both water and coffee by weight in grams, which makes things very easy. Huzzah metric system!
The first things you need to know are what size your brewing device is and how much coffee you want to end up with. (Don’t under- or overfill your device—choose one that’s the proper size for the amount of coffee you want to brew.) Let’s use a small BeeHouse dripper as an example. The manufacturer says it is designed to hold grounds for one to two cups of coffee. Let’s say you want one cup. One cup is eight fluid ounces. One fluid ounce of water is 29.57 grams. Let’s start with a 1:16 brew ratio and see what that means for your coffee dose (to make things easier, I’ve rounded all of the measurements to the nearest whole number):
Since you already have the calculation for the 16 part of the ratio (237 grams), all you have to do is divide it by 16 to get the coffee dose. That ends up being 15 grams (actually about 14.8, but I find it easier to adjust my dose if I start with whole numbers). This means you would start with 15 grams of coffee beans and 237 grams of water, grind, brew, and see how that tastes. Depending on what you think of the taste, you can adjust your dose accordingly, half a gram or so at a time. (As a heads up, 15 grams might be a lot more coffee than you’re used to using. One of the most common mistakes of people making coffee at home is not using a big enough dose. If you try using a 1:16 brew ratio and think your dose looks like too much coffee, I urge you to follow through and see what happens before reducing the dose.)
You can also apply the chart to different quantities and different devices. If you were brewing for a crowd using a large Chemex, you could use the chart to see that you would start with 1,419 grams of water and between 83 and 95 grams of coffee beans to brew six cups. However, if you own multiple devices, note that you likely will not be able to use the same brew ratio across all of them. As you’ll see in chapter 6, the ratios I use vary from 1:12 to 1:17, depending on the device.
Once I figure out the brew ratio I like for the device I’m using, I write it down and use it each time I make coffee. Most craft coffee shops do too, and that ratio becomes part of the device’s base specifications, or base specs. The point isn’t to reinvent the wheel each time you brew. Instead, you can use the base specs as a starting point. A coffee shop might adjust its specs daily (or at least every time they’re working with a new batch of coffee), a process called dialing it in, in order to optimize quality. At home, I rarely tweak mine. The base specs usually work well enough.
Choosing the Right Dose
Okay: Two tablespoons of ground coffee per six ounces of water
Better: 1:15 to 1:17 whole beans to water in grams
GRIND SIZE AND CONTACT TIME
Grinding coffee involves breaking whole coffee beans into smaller pieces. A whole bean, with its relatively small surface area, does not afford water much opportunity to penetrate it and extract the good stuff. Also, trying to extract coffee from whole beans would take forever, which isn’t practical. That’s why beans are ground up into big (coarse) or small (fine) pieces before being used—it makes it easier for water to extract coffee from them. Understanding how grind size affects extraction will help you adjust your cup to suit your preferences.
Grind size has a significant effect on your coffee’s extraction and, by extension, its flavor. Finer grounds give your dose a greater overall surface area than coarser grounds, which translates to more room for water to flow in and extract flavor. This means that if you start using finer grounds without changing anything else about the way you currently make coffee, you will end up with a higher extraction yield than usual. When water has more opportunity to penetrate the grounds and dissolve the coffee’s flavor compounds, more dissolved material ends up in your cup.
Of course, more isn’t always better. Because extraction happens faster with finer particles, you can easily overdo it. Brewing methods that use finer grounds tend to require less contact time with the water to make a yummy cup. Likewise, brewing methods that use coarser grounds tend to require more contact time with the water.
While finer grounds may extract faster, they don’t necessarily help the coffee brew faster. This is because grind size can drastically affect flow rate, or how quickly water passes through a pile of coffee (this applies to pour-over brewing methods more than full-immersion brewing methods; see page 46). Coarse grounds have more space between them, which means water can pass through them more quickly. Finer grounds are more compact, so water moves through them more slowly. Think of it like this: Would water travel faster through a column of gravel or a column of sand?
Unfortunately, there isn’t one special grind size that will guarantee you a better cup; great (or terrible) coffee can be made with all manner of grind sizes. To make things more mysterious, there are no universal grind sizes and no standardized language to talk about grind size beyond the terms fine, medium, and coarse, which are highly subjective. Further, different grinders come with different nomenclature. One grinder set to 14 might not produce the same size grounds as a different grinder set to 14. Other grinders may not even use numbers. There are scientific ways to measure particle size, but you need extra equipment, and it simply isn’t practical for the home brewer (or anyone).
GRIND REFERENCE CHART
For these reasons, it’s often simpler to compare the size and texture of the grind with more familiar kitchen items, like salt and sugar. In the Grind Reference chart above, I’ve illustrated the spectrum of grind sizes, along with a tactile comparison and the brewing devices covered in the next chapter that typically use each size.
Different devices generally work best within a certain range of grind sizes to better control the flow rate. If you use grounds that are too coarse for a device, the water will pass through them so quickly that you’ll end up with underextracted coffee. On the other hand, if you use too fine a grind, the water will move through the grounds at a snail’s pace (or even stop!), and you’ll end up with overextracted coffee. This is why, if you’re in a rush, you can’t just tighten the grind to make your coffee brew faster.
One big indicator that your grind size is too fine for your device—at least if you’re using a pour-over device—is the state of your coffee bed: if it looks muddy, the grind is likely too fine. Another indication is your water takes too long to draw down through the coffee bed. In chapter 6, I provide a target drawdown time for each of the pour-over methods. Overshoot that time and your grind might be too fine; finish ahead of schedule and your grind might be too coarse.
Devices also tend to be associated with certain windows of brewing times. A French press is among those with the longest brewing times and an AeroPress is among those with the shortest brewing times. That isn’t to say there is a single correct combination of grind size and contact time for each device, even if the manufacturer says otherwise. You can find multiple ways to make a great cup of coffee on one device; it’s just that success is probably more easily obtained in the windows described in the chart—at least for beginners. However, some devices are more versatile than others. For example, this book provides specs for both an eight-minute and five-minute French press method, and the coffee community seems to crank out endless wild recipes for the AeroPress.
It’s important to note that grind size is never truly uniform because roasted coffee beans, by their nature, break up irregularly. All grinders produce a distribution of grind sizes, from relatively large chunks to tiny fines. This is one of the reasons why it’s important to use a good grinder (and why I suggest that if you buy only one coffee implement, it should be a burr grinder), but I’ll discuss this further on page 84.
Grind Size and Taste
Too fine = thick mouthfeel, bitter flavors
Too coarse = thin mouthfeel, flat or sour flavors
Coffee is 98 to 99 percent water. Water is both an ingredient and, because it is a solvent, a tool. That means water deserves our attention. To start: funky-tasting water will produce funky-tasting coffee. In the United States, most of us are blessed with ready access to water. However, not all water is created equal. When making coffee, fresh, good-tasting water is key. For beginners, if you already have fresh, good-tasting water that flows directly from the tap, then go ahead and use it. If you don’t—that is, if the water has a perceptible smell or taste of any sort—consider using a simple carbon-filter pitcher or a similar device (assuming you’re not already doing so). Our water here in Chicago happens to taste like chlorine, as if the city is diluting pool water and running it through the pipes. My carbon-filter pitcher does a great job of filtering out that taste—in fact, a standard carbon-filter pitcher will filter out any chlorine tastes or odors (probably the most common issues with tap water in the United States) as well as a few kinds of metals. A variety of other more expensive filtering options are out there, but for home coffee brewers, a carbon-filter pitcher is likely all you need to fix subpar water.
When using a filter, however, the goal is not to remove everything from your water. That’s because water contains a bunch of minerals and other substances that help it to be a good solvent. For example, magnesium and calcium are particularly good at extracting coffee flavors. Soft or distilled water (water in which most or all minerals and impurities have been removed) is not a good coffee solvent. Distilled water may be necessary for your disgusting neti pot, but you should never use it to brew coffee—it cannot pull enough flavors from the coffee grounds, so your cup can end up tasting overly acidic (sour). However, mineral water is not the best option for brewing either, even though it might be chock-full of calcium and magnesium. Mineral water is often too hard, which results in dull, bitter coffee that lacks pleasant acidity.
A common complaint from those who have well water is that it’s too hard and causes non–coffee-related problems, like scaling and the need for extra soap when cleaning. Because of this, many households with well water use softening systems. If you’re in this situation and your coffee isn’t tasting good, try comparing coffee made with hard water to coffee made with soft water. If you can tell a difference, start using the water with the better result. If you don’t like either, you can try using natural bottled spring water (which is different from mineral water).
Many professional coffee shops have reverse-osmosis systems that filter their water and then add the right amount of calcium and magnesium back in. I have even seen shops sell their reverse-osmosis water to customers. This is completely unnecessary and almost criminal—there, I said it! A handful of companies also sell the right mix of minerals to turn distilled water into perfect coffee water. I haven’t yet tried that myself, but I suppose it’s good to know that it’s an option.
The SCA provides standards on water quality, which I’ve included below. The middle column is what the SCA suggests is perfect, and the right column offers wiggle room in some areas.
For beginners, this chart should at least suggest that freshness, cleanness, and the absence of chlorine are the most important factors to consider when assessing brewing water. For home brewers who are interested in water, it’s worth noting that the chart is sometimes vague and sometimes specific. Regardless of your level of interest in brewing water, you should know that it is unlikely that the water you have at home falls within all of the SCA’s ranges, and the chart certainly has its flaws. For example, recent studies suggest that the importance of something like TDS (how many minerals and other elements are in your water—not to be confused with TDCS, the term I use to specifically refer to the amount of dissolved coffee particles in coffee) as a measurement in and of itself is exaggerated. It’s also not practical for home brewers to test their water for all of these characteristics. I think of the SCA’s water standards as more of a “control what you can” type of guidance. Maybe you can’t control the number of TDS in your water, but water that tastes like chlorine? That you can control.
People who are super interested in water should read Water for Coffee by barista Maxwell Colonna-Dashwood and MIT coffee scientist Christopher H. Hendon. It explores how and why water changes coffee from a scientific perspective and suggests that many coffee professionals put too much emphasis on, for example, TDS. Determining the perfect water for brewing coffee is a developing science and is not completely applicable to the home kitchen, but the book offers a few points that are worth emphasizing to home brewers:
•Water makes coffee different from other craft products. The quality of coffee is determined by its flavor, just like with wine or beer. You can talk about the processing, mouthfeel, and flavor notes of all three beverages. But coffee beans also must be prepared (not just processed) with water, making it fundamentally different from wine and beer, which do not require any such preparation. On top of that, water is the primary ingredient in our beloved coffee, and it is not constant—it can vary from town to town. This means that about 99 percent of coffee’s composition is ever changing—that’s remarkable!
•Different types of water have various effects on coffee’s flavor. Because water varies from place to place and it’s not practical (or necessary, frankly) to make it uniform, you will get different results in your coffee cup depending on the kind of water you use. Even if there were a way to ensure that all of your other brewing variables stayed the same, using a different type of water than usual could have a drastic effect on your coffee’s flavor. This means that if you move or go on vacation, the specs that worked so well for you at home might not work so well in your new place—or maybe it works better!
All of this is simply to say that home coffee brewers should respect water and do what they can to control their water quality: filter out chlorine and avoid using distilled water or mineral water. There also may come a time when your water just doesn’t work with a specific type of coffee. Coffee is roasted to work with the roaster’s water, which might not align with what you have going on at home. In reality, it’s unlikely that this difference is going to affect your cup so much as to make it undrinkable. Any water issue is more likely to manifest like this: you have tried everything and your coffee never tastes right. Maybe it’s your water.
Conventional coffee wisdom says the ideal brewing temperature for water is usually between 195°F and 205°F (except for cold brew; see page 60). Note that this range is lower than water’s boiling point of 212°F—that’s the main takeaway here: water at a boiling temperature is too hot for making coffee.
Water temperature is important because it influences how the soluble compounds in coffee dissolve. The low end of the ideal temperature range is 195°F because it’s harder for water colder than that to dissolve many of the compounds that contribute pleasant flavors to your cup, meaning it might take longer for the water to do so. Water that’s too hot (like at the boiling point) dissolves too many compounds too quickly, which can result in bitter or astringent coffee.
At my house, I use a standard electric kettle to heat my water because it’s super fast, and I can’t stand to wait for water to boil. If I’m using a pour-over method, I transfer the water from the electric kettle to a gooseneck kettle, and the whooshing of the water during the transfer cools it down enough (on average, to close to 205°F) to be ready to pour so I don’t have to wait. (There are electric gooseneck kettles, but I like the setup I have now.)
You may have noticed that professional baristas often return the kettle to the heat source at times when they aren’t pouring, like after wetting the filter (see page 54). I’d say typically this isn’t necessary, especially if you are heating your water on a stove.
I’m a generally curious person, though, so I did some water temperature retention tests (warning: this goes kind of deep). In the past, I’ve defaulted to waiting only 30 seconds between taking the kettle off boil and pouring the water because a minute just seemed too long. However, when I tested this theory at home, I was surprised by how well my kettle retained heat. After 30 seconds, my water temperature was a rock-solid 210°F every time I tested it. After a full minute, it only dropped by another degree or two. At a minute and 30 seconds, it was around 207°F and after two minutes, it was around 203°F. After three entire minutes, the water only lost about 12°F on average, registering at 200°F during most tests—still well within the ideal brewing temperature range. How quickly the temperature of your water drops has a lot to do with your environment. On the day of testing, my room temperature was 78°F, and I used a kettle made of stainless steel, a material that retains heat well. If you’re interested in water temperature, try this same test in your own home with your own kettle.
Professional baristas use special equipment—usually water towers or kettles with induction plates that can gauge and hold certain temperatures—to ensure that the water they use is always on point. Although similar equipment is available to you, it’s probably not strictly necessary for home brewing. You could simply use a digital-read thermometer to check your water temperature while you heat it, but another approach is to take the kettle off the boil for about 30 seconds to a full minute before pouring. For the home brewer’s purposes, this should do just fine.
It should be noted that the act of pouring into a brewing device or brewing vessel significantly reduces water temperature. In one test, I noticed that when poured directly off boil into unheated ceramic mugs, my water immediately cooled to 200°F and, outside the warm embrace of stainless steel, continued to lose heat quickly until it reached around 160°F. That’s why many baristas try to account for this loss by preheating their devices and coffee mugs with hot water. These are both attempts to reduce the amount of heat lost as the heat transfers from the brewing water to the device and from the coffee to the mug, respectively.
All things considered, I doubt the heat retention of a device or vessel perceptibly changes the flavor of the brew. Under normal kitchen circumstances, I generally don’t bother to preheat my device unless it’s a by-product of my rinsing a paper filter—although it certainly doesn’t hurt anything if you do. Preheating ceramic, at least, does seem to slow down heat loss. In my tests with preheated mugs, the water temperature still immediately dropped to around 200°F, but the inevitable drop to even lower temperatures was markedly slower—meaning your coffee has a better chance of staying warmer for longer.
Elevation and Water Temperature
For every 500-foot increase in elevation, the boiling point of water decreases by 1°F. That means in a place like Denver, which is 5,280 feet above sea level, the boiling point of water is around 202°F, as opposed to the standard 212°F. Pretty wild! What does this mean for coffee folks who are living a mile up in the air? The boiling point of coffee is smack dab in the ideal temperature range for making coffee. As discussed, boiling coffee at sea level is generally a no-no, but in a place like Denver, maybe you can tool around with it. (For example, Boxcar Coffee Roasters in Denver makes its coffee using a boiling method.) Have fun!
When using a pour-over method, the way you pour the water over the grounds can affect the way your coffee tastes. Specifically, the pace and control of your pour have the biggest impact. There are probably as many perfected pour techniques as there are professional baristas, yet there isn’t much literature on the subject of pouring. It’s sort of an abstract concept, and it can sound a little ridiculous when you get down to it, but since you’re going to have to pour that water at some point, you might as well learn how pouring can affect your brew. Is pour technique beginner-level stuff? Probably not. Is a super-refined pouring technique strictly necessary for homemade coffee? No way. But beginners can apply a couple of easy pouring concepts and still taste a difference in their cup.
As I discussed previously, the amount of contact time the water has with the coffee directly corresponds to how many flavor molecules dissolve. As you’ll see a bit later on, the extent to which you agitate the water can also affect extraction. In other words, pouring quickly and sloppily can significantly (and negatively) influence the final outcome. Speaking as someone who used to just dump the water over the grounds, I can assure you that a slow, controlled pour bears noticeable results.
Performing this slow, controlled pour is easiest with a gooseneck kettle (see page 97). No, you don’t need one—and I’ve included methods in this book to make pouring easier if you don’t have one—but it certainly helps you control and direct the flow of the water.
There is much debate in the professional coffee community about two different types of pouring methods: continuous pouring and pulsing. I think either one is fine for the home brewer, but there are a few things to keep in mind no matter which technique you use:
•Don’t flood the coffee bed. The point of pour-over methods isn’t to drench the coffee grounds and have them soak in a pool of water. You want to keep the water level relatively stable so you can ensure that fresh water is continuously replenishing the bed as coffee drains from the bottom of the device. Why is this important? Fresh water is a better solvent than coffee water. (Of course, there are exceptions; see the V60 method on page 248.)
•Pour toward the middle. For most of your pouring time, you should be sticking relatively closely to the middle of the coffee bed. If you pour around the sides of the device, the water can make channels along the walls and bypass most of the coffee grounds. You can tell whether you’re hitting the sides of the device by taking a look at the filter once the water draws all the way down. There should be a thin layer of coffee, mostly made up of fines, around the sides of the filter just above the bed. If there are clean patches of filter (called balding in the biz), then you know water was hitting the sides of the device and taking the path of least resistance downward. The other issue with this is what’s called fines migration. Because fines tend to stick to the sides of the filter, water can wash them to the bottom of the filter, where they clog up everything, sending your contact time straight to hell.
•Evenly distribute the water. Although it’s best to stick to the relative middle of the coffee bed, you never want to pour directly into one spot. This will create a channel that allows water to bypass most of the grounds. To avoid this, try to pour in a rhythmic pattern of small circles or figure eights or whatever your heart desires. Professional baristas do this in lots of ways (and many have strong opinions about which is right), but for the home brewer’s purposes, the point is to keep the water moving so it is evenly distributed across the entire bed. When the water drains through the grounds, the bed should be as flat as possible. If you notice slopes or divots once all of the water has drained, you know that you’ve been favoring one area over another.
•Keep the coffee in the coffee bed. While it’s common to see fines stuck to your filter, you don’t want to see thick walls of grounds stuck all the way up the sides of the brewing device. (Unless there is an exception, which there always is; again, see the V60 method on page 248.) Large chunks of grounds stuck to the filter above the bed are called boulders. The thicker and higher the boulders are on the sides of the filter, the less coffee is actually coming into contact with the water for the correct amount of time. In some of my brew methods, I recommend taking a quick lap or two around the outer reaches of the bed to make sure you are pushing those grounds back down into the slurry.
•Make your time. Besides making sure the coffee is evenly and completely in contact with the water, the controlled pour is also supposed to control the time in which the coffee is in contact with the water, the brewing time. This book’s specs outline the target brewing time for each method in chapter 6. For pour-over methods, this includes the time you pour and how long it takes the water to filter through the bed once your final beverage weight is met. If you pour too fast, the water won’t get a chance to extract all of the goodness from the grounds. If you pour too slowly, you might end up with overextracted coffee. Remember, if you feel like you are pouring as slowly as you can and the water is still draining too quickly, your grind might be too coarse. If you are consistently hitting your brew-time mark but the water is drawing down achingly slowly, your grind might be too fine. (See page 27 for more on this.)
Getting the hang of pouring takes time, but it gets easier the more you do it. Eventually, you, like professional baristas, may develop a muscle memory that makes pouring second nature. Will that happen to you? Who knows! But good pouring technique is fairly simple to master either way.
Plenty of baristas feel that if you’re preparing pour-over coffee, you should be continuously replenishing the water in the device with a slow, steady stream from your kettle. This is called continuous pouring. The goal is to keep the slurry at a low, consistent height and to keep the flow rate constant throughout the length of the pour. Ideally, the stream of water should never break, not even to a dribble.
Advocates of this method often say it’s gentle (little agitation), meaning you can use finer grounds that can potentially result in a tastier cup. Many also claim that devices like the V60 and the Chemex literally require such slow, controlled pouring because the devices themselves do very little to control flow rate.
This kind of pouring is essentially impossible without a gooseneck kettle, and it certainly requires a bit of effort to master. For best results, the kettle should be about three-quarters full (the flow rate out of the spout changes more drastically as the water level in the kettle decreases, which can be tricky for beginners), and it can feel a bit heavy at first. Over time, people supposedly develop a “barista muscle,” and it becomes easier for them to hold and control a full kettle in one hand for the entire pour time. (I, for one, remain a weakling to this day.) It’s also helpful to practice pouring into your device with a filter but without the grounds. Practice continuous pouring with a familiar amount of water—say, 250 to 400 grams. Time yourself and start over if you break your stream. See how slowly you can go. If you can pour 250 continuous grams of water in three minutes or longer, you can probably do anything.
A Note about Agitation
Agitation happens when the coffee grounds move around in the water. Agitation exposes coffee particles to fresh water more quickly, which in effect speeds up extraction. A certain level of agitation happens with most devices because you must introduce the water at some point, and that’s going to stir things up a bit. As the water level rises and falls, the coffee grounds move with it—that’s more agitation. Most of the time, you probably want to keep extra agitation, beyond what’s happening as you pour the coffee, to a minimum. However, some methods, particularly full-immersion methods, may benefit from a quick stir or two. How do you know how much to agitate? It’s just something you’ll have to pick up with practice. But in the beginning, it’s a good skill to keep in mind and work toward developing.
Pulsing is a different kind of pouring technique. Instead of continuously pouring the water, you take breaks at certain intervals to allow the water to drain. How often you break and for how long is highly variable—everyone has their own opinions about what’s best for what kind of device. Generally speaking, one break every 50 to 60 grams is fairly standard.
While pulsing involves taking a break in between pours, that doesn’t mean it’ll draw out the brewing time. Pulsing necessitates pouring faster (because of the breaks), and the target brewing time on a pour-over device generally remains the same whether you pulse or continuously pour.
In my experience, pulsing is more forgiving and easier to master than continuous pouring. Pulsing is way less stressful for one thing, and it lets you easily make adjustments to your speed as you go. Pulsing also allows you to brew smaller batches of coffee and still maintain the proper contact time.
No matter which technique you use, blooming your coffee—that is, thoroughly prewetting the grounds with a small amount of hot water before you continue pouring—is another easy way to improve your cup. It sounds silly: How could just wetting the grounds and waiting have a significant effect on the end flavor of the cup? But it seems to. At base, the heat and moisture provided by the bloom prepare the coffee for extraction, and they do so in two ways:
•Releasing carbon dioxide. Fresh coffee contains a lot of carbon dioxide because it gets trapped in the beans during the roasting process. When you wet coffee grounds, they swell and bubble as the carbon dioxide is released. (One good indicator that your coffee has gone stale is that there is little to no bubbling during the bloom). Coffee naturally off-gasses carbon dioxide, but hot water speeds up the process. Carbon dioxide, as anyone who has drunk soda water can tell you, is bitter. Blooming makes sure all of that bitter carbon dioxide doesn’t end up in your cup.
•Beginning the extraction process. Blooming ensures that the beans’ carbon dioxide gets out of the way of the other solubles before real extraction starts. If the carbon dioxide isn’t released, the gas repels the water, providing the other solubles with a protective shield. This makes it more difficult for the water to reach these solubles, which makes it harder for you to make a tasty cup.
How much water should you pour for a bloom? A good rule of thumb is to double the weight of your dose and use that amount of water. For example, if your dose is 14 grams (about 2 tablespoons) of coffee, your bloom weight would be 28 grams (about 41⁄2 tablespoons) of water. You want enough water to soak the grounds but not so much that it streams through the device (some dripping is okay). Adding too much water at once can trap the carbon dioxide and defeat the purpose of the bloom. How long should you wait before continuing with the brew? A good bloom time is about 30 to 45 seconds, depending on the coffee’s freshness, roast, and dose. For example, fresh, light-roasted coffee usually needs a longer bloom time, as do bigger doses. Once the bubbles start to slow, that’s a good sign that the bloom time should be ending.
At this point you might be thinking: Why only 30 to 45 seconds? Why not wait until all of the bubbles have completely subsided? For one, the bubbles usually don’t stop. Two, if carbon dioxide is escaping, you can bet your butt that other volatile aromatic compounds are escaping as well. Volatile aromatics are incredibly delicate and prone to wafting off into the ether—that’s why they are called volatile!—but it’s important to keep them in the coffee because they greatly contribute to flavor (aroma is a big part of flavor; see page 193).
Zero That Scale!
Don’t forget to zero your scale before you start pouring water for the bloom. The weight of neither the device nor the coffee should be included in the bloom weight.
DIALING IT IN
As mentioned earlier, when coffee professionals use the phrase “dialing it in,” they are talking about using trial and error to determine the correct brew variables, or specs, for a cup of coffee (or a shot of espresso). In other words, they’re talking about fine-tuning their brew. As you’ve seen, all of the brew variables discussed in this chapter can affect the outcome of the cup, so it’s important to get them just right.
Professional baristas may need to tweak some of these variables as often as daily. This is because brew variables simply are not constant. As previously discussed, grind size is not uniform, and water temperature can vary throughout the brewing time. On top of that, the device, type and age of the bean, pouring consistency (in the case of pour-over methods), and even the weather outside can all affect how a cup turns out—yes, even temperature and humidity can influence the way your coffee brews! That’s because coffee is hydroscopic, which means it sucks moisture from the air. This plumps up the beans (at least on a molecular level), which may make them denser once they are ground. One solution for this might be to coarsen the grind. This issue is more common with espresso, but it’s a good example of how certain nonobvious variables can affect the cup and force some changes to the base specs.
Another common instance of specs needing to be tweaked is when super-fresh beans are used instead of not-so-fresh beans. A professional barista might use a slightly finer grind than usual with very fresh beans because they contain a lot of carbon dioxide and the gas can interfere with extraction. A finer grind can help counteract this interference early on, and as the week goes by, the barista may loosen the grind accordingly.
While you are learning and dialing it in at home, be sure to change only one brew variable at a time. That way, you can track your progress. If you change two or more variables at once, you’ll never be able to draw a definitive line between the adjustment and the result. It’s also easier to understand and remember each variable’s effects when you test them individually. For example, if your coffee is too strong and you think either the brew ratio or the grind setting is off, only change one at a time to see which one is the problem.
As you brew more and more coffee, the process will become less like trial and error and more like concrete decision-making. You’ll eventually be able to identify problems and ways to solve them quickly without using a lot of guesswork. You can also learn some tips and strategies for troubleshooting problems in the Appendix (see page 251).
YOU MAY BE WONDERING why this chapter comes before the chapter on beans, which would seemingly be the first step to better coffee. Let me put it to you this way: you can put the best beans in the world into a horrible automatic machine and it will turn them into bad coffee as quick as you please (you’ll learn why in this chapter). If you don’t have a device with the potential to make great coffee, then even great beans can’t make it happen.
The simple fact is that the device you choose to brew on—and how you choose to brew with it—has a measurable impact on your cup. You have a series of important device-related choices ahead of you, and this chapter will help you make them. There is a ridiculous number of options in the world of brewing devices, but the first favor I did for you is reduce that number. This chapter focuses on 10 devices, including my favorites. Any one of them could be a great choice, but the point of this chapter is to help you make the best choice for you. That’s why I focus on the factors that tend to be most important to home brewers looking to buy a new brewing device: ease of use, availability, and affordability.
However, you can’t make a good purchasing decision without considering the other types of equipment you want (or don’t want) to invest in—most brewing devices require a bit of company. This chapter outlines some of the other additions you can make to your brew bar—filters, grinders, scales, kettles, and more—and how they can improve (or damage) your cup.
FULL-IMMERSION VERSUS POUR-OVER BREWING DEVICES
There are two primary ways to manually brew coffee: the full-immersion method and the pour-over method. When choosing a brewing device, this is the first decision you’ll have to make: Which method do you want to use? As you’ll see, the kind of method you choose will affect not only the characteristics of your brew but also how much money you spend, how much time and energy you use making coffee, and how much additional equipment you might need.
Full-immersion (often simply called immersion) brewing involves essentially the same process as what you would use to steep tea. The water is introduced all at once, and the grounds soak fully submerged. The water then penetrates the grounds to extract the flavor and texture compounds. At the very end of the brewing process, the grounds are filtered from the coffee.
Pour-over brewing, on the other hand, involves pouring water over the grounds and through a filter. The key there is to introduce the water slowly throughout the length of the brew cycle. As it washes through the grounds, the water takes the coffee’s flavor and texture compounds with it.
One big advantage of immersion devices is that they tend to be a bit easier to master than pour-over devices because they do not require a high level of technique or any special equipment. Immersion brewing is a set-it-and-forget-it way of making coffee. In contrast, pour-over devices require a certain degree of technique to make sure enough water is reaching the grounds for the correct length of time. Such precision generally warrants an extremely slow and controlled pour, a feat most easily accomplished with a gooseneck kettle. This kind of attention to detail is less important when it comes to immersion brewing, so if you aren’t interested in investing in extra equipment right off the bat, you may want to reconsider using a pour-over method.
Keep in mind, however, that all devices exist on a spectrum. As you’ll see in the device profiles starting on page 69, some pour-over devices require less technique (and less additional equipment) than others.
A NOTE ON THE AUTOMATIC COFFEE MACHINE
Even though coffee is simple, I’ve just spent several thousand words talking about its various facets and making suggestions that will help you replicate coffee from a shop at home. It’s not difficult to see why pushing a single button on an automatic coffee machine is much more tempting than dealing with any of this.
The problem is that most standard automatic coffee machines will never replicate coffee-shop quality at home—even if you opt for drip coffee instead of pour over when you go out. That’s because most automatic machines simply aren’t designed for optimal coffee brewing, for two main reasons:
•Most automatic machines cannot reach the proper brew temperature quickly enough or maintain it for the length of the brew cycle.
•Most automatic machines do not achieve the proper contact time.
In other words, automatic coffeemakers have temperature and time working against them.
On the other hand, a manual device allows you to easily beat a typical automatic machine on both fronts. Here’s an anecdote to put this into perspective. At the office where I work, we mostly use a Melitta pour-over system, but we also have a standard automatic coffee machine. When we make pour-over coffee, we do not consistently or precisely measure the water or the beans, and we don’t use a gooseneck kettle. We don’t have scales or even volumetric measuring cups, and we don’t use a good grinder (yet). In short, there is very little special technique involved with our pour-over method. We have work to do, after all! Still, coffee made with the pour-over system is perceptibly better tasting than that made with the automatic machine, even though the automatic machine is arguably making coffee more consistently than we humans are. But, at the very least, we humans are bringing the water up to the correct temperature, and the design of the Melitta device slows down the pour time—even if we pour into it as much water as we can as quickly as we can.
Does using the Melitta this way result in craft coffee-shop coffee? Not usually, but sometimes it does. Either way, it is good enough for the context of our situation—and, again, it is perceptibly better than the coffee made with the machine. I cannot stress this enough. It’s crazy!
This isn’t to say that no automatic machines can brew high-quality coffee. Most coffee shops use automatic drip machines that can produce delicious coffee, but those are for commercial use and baristas calibrate them regularly. The Specialty Coffee Association (SCA) tests consumer-grade coffee machines each quarter, and if a machine meets its standards (mainly the time and temperature considerations described previously), it becomes an SCA Certified Home Brewer, and you will likely be able to make a good cup with it. As of this writing, that list includes the following machines:
•Bonavita 8-Cup Digital Coffee Brewer model BV1900TD (retail: $199.95)
•Bonavita 8-cup Coffee Brewer model BV1900TS (retail: $189.99)
•Behmor Brazen Plus Customizable Temperature Control Brew System (retail: $199)
•KitchenAid Custom Pour Over Brewer model KCM0802 (retail: $230)
•KitchenAid Pour Over Coffee Brewer model model KCM0801OB (retail: $199.99)
•OXO On 12-Cup Coffee Brewing System (retail: $299.99)
•OXO On 9-Cup Coffee Maker (retail: $199.99)
•Technivorm Moccamaster (retail: $309 to $360)
•Wilfa Precision Automatic Coffee Brewer (retail: $329.95)
This isn’t an exhaustive list of automatic coffeemakers that can make high-quality coffee, but it’s a good place to start your research if you are in the market for one. As you can see, they are all rather pricey, which makes them inaccessible to a lot of people who want to make coffee at home.
It’s also important to realize that simply owning a machine doesn’t mean you’ll be able to make foolproof coffee without thinking about anything. The machine may take care of water temperature and brewing time for you, but you still need to make decisions about the brew ratio, the grind size, and what kind of coffee to use, and you need to operate the machine according to the manufacturer’s instructions.