The Coffee
Compendium
From seed to cup, the journey behind every coffee we pour. Built on the SCA Introduction to Coffee, V3.0 (2024), expanded with the language and craft of competition baristas.
Seven sections, four practice tools.
What we mean when
we say specialty.
In 2024, the SCA changed how it defines specialty coffee. The old definition asked, "did this coffee score 80 points or more?" The new one asks something different.
Specialty coffee is a coffee or coffee experience recognized for its distinctive attributes, and because of these attributes, has significant extra value in the marketplace. SCA, 2024
The shift matters. Specialty is no longer a binary line at 80 points. It exists on a continuum. The more distinctive positive attributes a coffee has, and the more those attributes matter to a particular person or market, the more specialty it is to them.
Two kinds of attributes
What's in the cup itself
The properties you can taste, see, or measure in the coffee. Flavor profile, bean size, roast color, chemical composition.
When you describe a coffee as "bright, with notes of stone fruit and a syrupy body," you're talking about intrinsic attributes.
What you know about it
Information about the coffee that lives outside the cup. Origin, producer name, processing story, certifications, sustainability claims, brand.
When a customer hears "this is from a single farm in Panama, picked by hand, naturally processed," they're hearing extrinsic attributes that shape how they value the coffee.
Both add value. A coffee can be distinctive because of how it tastes, because of where it comes from, because of how it was grown, or any combination. Our job behind the bar is to make both sides legible to the customer.
Six activities, many actors.
The simplest map of the coffee industry has six key activities. Each one is a craft. Each one shapes what ends up in the cup.
Many actors operate beyond these six. Government agencies, NGOs, certifiers, transporters, equipment manufacturers, researchers, financiers, baristas, and consumers all shape the global coffee system. The SCA Coffee Systems Map illustrates the full complexity.
A plant from East Africa,
now grown in 50+ countries.
Coffee's spread tracks the spread of trade, religion, and colonialism over the past four centuries.
A condensed history
The Coffee Belt.
Coffee grows between the Tropics of Cancer (23.5°N) and Capricorn (23.5°S).
Four major regions
- South America: the largest regional producer. Brazil leads the world in total volume and in arabica.
- Central America: smaller volumes, often with distinctive terroir and high cup quality.
- Africa: the genetic origin of arabica. Ethiopia, Kenya, Rwanda, Burundi.
- Asia & Oceania: Vietnam dominates robusta. Indonesia produces both species across many islands.
Production today, 2024/25
Based on ICO and USDA data for coffee year 2024/25.
Arabica's share of global green bean exports rose to 63% in 2024/25 as Vietnam and Indonesia recovered robusta output after weather-driven shortages in 2023/24.
Two species do most of the work.
Arabica (left, elliptical with an S-shaped center cut) and robusta (right, rounder with a straight cut).
Coffea arabica emerged in Ethiopia and South Sudan hundreds of thousands of years ago. It's the species behind the majority of specialty coffee today.
Coffea canephora, commonly known as robusta, was first cultivated in present-day DR Congo around 1870. It tolerates lower altitudes, higher temperatures, and more pests. It contains roughly twice the caffeine of arabica.
Other species exist and are cultivated too: Liberica, Excelsa, and others. Hybrids and a wide range of varieties within each species add further diversity.
| ATTRIBUTE | ARABICA | ROBUSTA |
|---|---|---|
| Chromosome number | 44 (allotetraploid) | 22 (diploid) |
| Optimal temperature | 15 to 24 °C | 24 to 30 °C |
| Optimal rainfall | 1,500 to 2,000 mm | 2,000 to 3,000 mm |
| Optimal elevation | 1,000 to 2,000 masl | Below 800 masl |
| Caffeine content | 1.0 to 1.5% | 2.0 to 3.0% |
| Pest and disease resistance | Lower | Higher |
| Yield per plant | Lower | Higher |
| Acidity | Higher intensity | Lower intensity |
| Sweetness | Higher intensity | Lower intensity |
| Typical flavor character | Often fruity, floral, citrus | Strong, earthy, smooth mouthfeel |
| Market price | Higher | Lower |
Coffee is a seed.
Each cherry contains two seeds (coffee "beans") wrapped in layers of pulp, mucilage, parchment, and silver skin.
Why this matters behind the bar
Every layer in the cherry plays a role in processing. The pulp and mucilage are sugar-rich and home to the microbes that drive fermentation. The parchment is the protective shell that comes off during dry milling. The silver skin is the thin film you see flaking off after roasting (chaff).
When a customer asks what the difference is between a "natural" and a "washed" coffee, you're really talking about which of these layers stayed on the bean during drying, and what happened in the time before drying began.
The most important
chapter for a barista.
Processing prepares coffee seeds for stable transport and storage. That's the textbook definition. But for a barista, processing is where most of the flavor character you'll talk about with customers is actually shaped.
A washed Ethiopian and a natural Ethiopian can come from the same farm, the same variety, the same harvest, and taste like completely different coffees. The reason is what happens in the hours and days between picking and drying.
What is fermentation, really?
Coffee fermentation is a controlled microbial process. After harvest, microbes (yeasts and bacteria) feed on the sugars in the cherry's mucilage. As they consume sugars, they produce acids, alcohols, esters, and other compounds. Many of these compounds get absorbed into the seed itself. Others change the seed's chemistry by altering its surface environment.
The processing method is essentially a decision about how much fermentation to allow, under what conditions, and for how long.
Process is a question of how much fruit, how much oxygen, and how much time. A WORKING HEURISTIC
The major methods
Cherries are pulped mechanically right after harvest. The mucilage that remains on the bean is then broken down by microbes in fermentation tanks (sometimes with water, sometimes dry). Once mucilage is gone, beans are washed clean and dried in parchment.
Fermentation is short (12 to 72 hours typically) and the sugar source disappears once mucilage is removed. Less time, less fruit, less microbial influence on the bean.
Clean, transparent, articulate. Higher perceived acidity. Lighter, often tea-like body. The terroir shows through.
Common descriptors: nutty, cocoa, sweet, citrus, stone fruit, floral, black tea, bergamot.
Whole cherries are laid out to dry intact, fruit and all. The mucilage and pulp stay around the seed throughout the entire drying period, which can stretch to three or four weeks.
Fermentation continues across that whole window. The sugars in the surrounding fruit slowly transform, and the seed absorbs those compounds over time. Much higher microbial influence.
Heavy, fruit-forward, often jammy. Lower perceived acidity. Fuller, syrupy body. Distinctive personality.
Common descriptors: blueberry, strawberry, red wine, dried fruit, raisin, rum, tropical fruit, chocolate.
Cherries are pulped to remove the outer skin, but the mucilage stays on the bean during drying. The sticky, sugar-rich mucilage looks like honey on the parchment, hence the name.
Producers categorize by how much mucilage is left and how long it stays during drying: white, yellow, red, black honey. More mucilage and longer drying push the cup toward natural character.
A middle path. Cleaner than natural, sweeter than washed. Balanced body, structured acidity.
Common descriptors: brown sugar, honey, maple, stone fruit, milk chocolate, caramel.
& experimental
Whole cherries (or pulped beans) ferment inside sealed tanks where oxygen is removed or controlled. Without oxygen, a different set of microbes dominates, and the chemistry shifts dramatically.
Producers can also vary temperature, pH, time, and add other inputs (yeasts, fruits, even spices) to push specific flavor directions. This is the frontier of processing innovation.
Intense, often polarizing. Distinct fruit, candy, wine, or spirits character. Sometimes funky, sometimes pristine.
Common descriptors: tropical fruit, lychee, passion fruit, rosé, whiskey, cinnamon, gummy candy. Can be controversial.
Two ways to say
the same thing.
A barista needs both lenses: the technical vocabulary for internal calibration with the team, and the warm, accessible language that meets a customer where they are.
If a customer orders our natural Ethiopia
How we calibrate
Natural process coffee from Bensa, raised-bed dried 18 to 22 days. Heirloom varieties. We expect medium acidity with a syrupy mouthfeel, dominant berry and stone-fruit aromatics, and a sweet, dried fruit lingering aftertaste.
Brew watchpoint: extraction tends to mute the fruit if TDS pushed too high. Coarser grind, shorter contact, or higher ratio if the cup tastes flat or boozy.
How we share it
This is a natural process coffee from Ethiopia. The cherries dried with the fruit still on, so the bean soaked up a lot of that flavor over several weeks.
"You'll taste a lot of berry and stone fruit, like a really good fruit jam. It's softer in acidity than most Ethiopias, with a syrupy feeling in your mouth."
If they're new to natural coffees, mention it can be fruit-forward in a way that surprises people on first sip.
If a customer orders our washed Panama Geisha
How we calibrate
Fully washed Panama Geisha. 72 hour wet fermentation. Higher perceived acidity, delicate body and silky mouthfeel, with jasmine, peach, bergamot flavor profile.
Brew watchpoint: a clean cup with the room for acidity to read clearly. Watch for sour at the front of the palate (likely underextracted) versus a balanced citrus brightness.
How we share it
This is a washed Geisha from Panama. Geisha is a celebrated variety known for its delicate, tea-like character. The fruit was removed right after picking, so what you taste is the variety itself, expressed cleanly.
"Expect jasmine and bergamot in the aroma, peach and a hint of citrus on the palate, with a silky, almost tea-like body. It's bright but very delicate."
Set the expectation up front: a Geisha drinks more like a fine tea than a typical cup of coffee. If they were hoping for chocolate and nuts, gently steer them toward another option.
Heat unlocks the cup.
Roasting is the chemical translation from green coffee to brown coffee. Time and temperature, carefully controlled, drive hundreds of reactions: Maillard browning, caramelization, the release of CO₂, the unfolding of aromatic compounds locked in the green bean.
The five stages
Beans nearly double in size by dark roast. Acidity diminishes the longer the roast goes. Sweetness peaks somewhere in the middle. Body and bitterness rise into the dark end.
Lighter vs. darker, side by side
What it tends to do
- Acidity: pronounced, often bright
- Sweetness: fruit-driven, varied
- Body: lighter to medium
- Bitterness: lower
- Aromas: floral, fruity, sweet, origin character preserved
What it tends to do
- Acidity: diminished
- Sweetness: caramelized, less fruit-forward
- Body: fuller, heavier
- Bitterness: higher
- Aromas: roasted, nutty, chocolate, sometimes smoky
Roasted coffee
starts staling immediately.
There are four enemies of fresh coffee. The job of a bag, a hopper, or a home canister is to keep all four at bay.
- Store roasted coffee in an airtight container with a one-way degassing valve.
- Keep it in a cool, dark cabinet. Not the fridge. Not the freezer.
- Keep it away from strong-smelling foods or spices.
- Buy whole bean, grind just before brewing.
Five senses,
seven components.
Sensory assessment is the shared language of the coffee world. It is how we choose which coffees to buy, how we calibrate roast profiles, how we dial in brewing, and how we describe what's in a cup to a customer.
Flavor is not just taste. Flavor is the combination of taste (what your tongue detects), smell (what your nose perceives both directly and retronasally through the back of the throat), and mouthfeel (the physical sensation of the liquid). A large share of what we call "flavor" actually comes from smell.
Coffee sensory assessment engages all five senses, with smell and taste doing most of the work.
The five basic tastes
Only five tastes exist as distinct receptor sensations: sweet, sour, bitter, salt, and umami. In coffee, sourness and bitterness are the most intense.
Everything else we call "taste" (chocolate, berry, citrus, floral) is actually smell, perceived as aromatic compounds rise through the back of the throat while we sip. This is why a head cold flattens coffee.
Spicy is not a taste. It's a chemical irritation sensation. Same with astringency, which is the puckering feeling of dryness in the mouth.
Seven components
every cup is judged on.
When SCA-trained judges (and Brewers Cup competitors) evaluate a coffee, they assess these seven components. These are the building blocks of the vocabulary we use behind the bar.
A shared vocabulary
for describing taste.
SCA Coffee Taster's Flavor Wheel. Inner ring: broad families. Outer rings: increasing specificity.
How to use it
Start at the center with broad categories: fruity, floral, sweet, sour, green, roasted, spicy, nutty, cocoa, other.
Move outward as confidence grows. "Fruity" becomes "berry" becomes "blueberry." "Sweet" becomes "vanilla" becomes "vanillin."
The wheel is a tool for calibration. When two baristas can both point to "cocoa, brown sugar, citrus" on the wheel, they share a frame of reference. The customer doesn't need the wheel to understand the words.
Use the explorer below the next time you cup a new coffee. Practice landing on the broad category first, then refine.
The standardized
tasting protocol.
Cupping is how the coffee industry compares coffees on equal footing. Every cup brewed the same way, so the only variable is the coffee itself.
We cup every roast batch. We cup every new green coffee that arrives. We cup before we put a coffee on the menu. The slurp is part of the craft.
Water does the work.
A brewed coffee is roughly 98.5% water by mass. The other 1.5% is the dissolved compounds water has pulled out of the grounds. Everything we taste lives in that small fraction.
Water quality matters
The water has to be clean, odor-free, and free of chlorine. Chlorine and chloramine bind to coffee compounds and create flat, dull, sometimes medicinal cups. Iron, lead, and other contaminants do their own damage.
The SCA publishes target water specifications. Brewers Cup competition water meets these targets:
| PARAMETER | TARGET | RANGE |
|---|---|---|
| Total dissolved solids (TDS) | 85 mg/L | 50 to 125 mg/L |
| Calcium hardness | 51 mg/L (3 grains) | 17 to 85 mg/L (1 to 5 grains) |
| Total alkalinity | 40 mg/L | at or near 40 mg/L |
| pH | 7.0 | 6.5 to 7.5 |
| Sodium | 10 mg/L | at or near 10 mg/L |
| Chlorine / chloramine | 0 mg/L | must be zero |
| Odor and color | Clean, clear | no exceptions |
For a barista on the floor: if your water tastes off, your coffee will too. A well-calibrated filter is one of the most important pieces of equipment in any café.
Every brewing device
does one of these things.
A small set of levers.
Extraction is water dissolving compounds from coffee. Different compounds dissolve at different rates. Acids and aromatics come out first. Sugars next. Bitter and woody compounds last.
Sour means under-extracted. Bitter means over-extracted. Sweet, balanced, juicy lives in between. THE EXTRACTION COMPASS
The levers you control
- Coffee to water ratio. The SCA Golden Cup target is 50 to 60 g of coffee per liter of water for filter brewing. A useful starting point for V60: 15 g coffee to 250 g water (60 g/L), 1:16.7 ratio.
- Grind size. Finer grind, more surface area, more extraction. Coarser grind, less surface area, less extraction. Adjust grind first when troubleshooting.
- Water temperature. 90 to 96 °C for hot brewing. Higher temperature extracts more. Lower temperature extracts less.
- Time. Longer contact, more extraction. Shorter contact, less.
- Turbulence. Stirring, pouring technique, agitation all increase extraction by exposing fresh grounds to fresh water.
Practical brewing rhythm
- Grind immediately before brewing. Aromatics escape fast once cell walls break.
- Bloom the grounds with 2 to 3 times their weight in water. Wait 30 to 45 seconds for CO₂ to escape.
- Pour with intention. Even saturation creates even extraction.
- Taste, adjust, taste again. The cup is the final judge.
Clean equipment is
part of the recipe.
Coffee oils go rancid quickly. Old residue on group heads, grinders, and brewers contaminates every subsequent cup with stale, bitter notes that the customer will taste before they can name.
Routine, scheduled service
Performed to maintain proper function and prevent unexpected failure.
- Daily back-flush of espresso machine group heads
- Daily grinder hopper and burr cleaning
- Weekly deep clean with detergent
- Filter changes on schedule, not when problems appear
Repair after failure
Unplanned. Performed after equipment has already failed, to restore function.
Reactive maintenance is more expensive and more disruptive than preventive. The goal of a well-run café is to push as much work as possible from the reactive column to the preventive one.
What baristas are
actually evaluated on.
The World Brewers Cup is the highest stage for filter-coffee craft. The criteria judges use there are the same criteria customers use, often without realizing it, every time they walk into a café.
The judges are looking for a champion who prepares brewed coffee of exemplary quality, delivers outstanding attention to detail, can articulate the taste experience offered by their brewed coffee, and delivers an exceptional overall coffee service experience. WBrC RULES, §14.1
Strip away the stage and the time limits, and that is just a description of a great barista on a regular shift. Quality in the cup. Attention to detail at the bar. Clarity when talking about what's in the cup. A service experience that makes someone's day a little better.
Two halves of every coffee service
In competition, baristas are evaluated on two scoresheets: the Cup Score (the coffee itself, the seven sensory components above) and the Barista Evaluation (what the barista does and says).
Behind the bar, both halves matter. A delicious coffee served by a barista who can't talk about it leaves money on the table. A talkative barista who can't brew a good cup wastes everyone's time.
Four pillars of craft.
These are the four scoring categories on the Brewers Cup Barista Evaluation scoresheet. They translate directly to daily work.
- Use words that match what's actually in the cup
- Calibrate against your colleagues during cupping
- Lean on the SCA Coffee Taster's Flavor Wheel
- "I'm not sure" is more honest than a guessed word
- Clean as you go, not at the end
- The customer sees everything. Wipe the rim before serving.
- Mise en place. Tools where you reach for them.
- If something breaks or spills, address it without making it a scene
- Know your coffees: origin, farm, variety, process, roast date
- Know your brewing: ratio, grind, time, why those choices
- Connect cause to effect. "We grind coarser for this because…"
- Read on your own. Q-Grader notes, Sprudge, podcasts, books.
- Politeness and attentiveness are baseline, not bonus
- Concise beats elaborate. Specific beats generic.
- Read the room. A morning regular wants different energy than a first-time visitor.
- The presentation enhances the cup, never overshadows it
Every customer interaction is a small coffee service. Treat it like one.
Four tools to keep
building the craft.
Use these to dial in brews, expand vocabulary, connect process to flavor, and test what's stuck.
Brew calculator
Pick a method, set your dose, dial in the ratio. The water is calculated for you. A common pour-over target is 1:16 to 1:17.
A balanced V60 starting point. Adjust grind and ratio to taste.
Cupping vocabulary explorer
The nine families on the SCA Coffee Taster's Flavor Wheel. Tap a family to see the descriptors inside, with notes on what they actually mean.
Process-to-flavor mapper
Pick a processing method. See the expected flavor profile, the technical vocabulary, and the line you'd use with a customer.
Knowledge check
Twelve questions across the curriculum. Sample style: matches the SCA written exam (multiple choice, single correct answer). Tap your answer to see feedback.