The Bad Coffee Guide to Specialty Coffee (A Glossary)
Specialty coffee has a problem. I initially typed out that it has a "language problem", but I don't think that's quite true. As with any industry, it comes with it's own terminology that can feel esoteric to the everyday enthusiast. The problem as I see it is that coffee professionals take it for granted, assuming that everyone understands these words and phrases.
I've been guilty of it too, even though I'm aiming to promote a more approachable way into specialty coffee. Such language can leave newcomers feeling frustrated, confused, and opting for a bog-standard coffee experience, get in and out, over and done with. JUST GIVE ME THE CAFFEINE.
Don't be intimmidated! Let's demystify some of these terms. From the difference between a washed and a natural coffee to the mysterious world of grind size, roast development and processing methods that sound like they've been borrowed from a chemistry lab.
You don't need to memorise any of this. That's what this page is for.
The bean: what are we actually drinking?
Coffee cherry
Coffee grows as a fruit, usually called a cherry. Inside are typically two seeds, which become the coffee beans we roast. The fruit is picked, processed, dried and milled before those seeds reach a roastery. Yes, coffee is technically a fruit drink. No, that doesn't make your morning espresso one of your five a day.
Arabica
Coffea arabica is the species behind most specialty coffee. It can offer a huge range of flavours, from delicate florals to chocolate and nuts. Its character depends on far more than the species alone. This plant grows slowly, at high altitudes, meaning the sugars in the flesh of the coffee cherry develop slowly adding to the flavour of the coffee.
Robusta
Coffea canephora, commonly called Robusta, is a different coffee species. It's generally more caffeine-rich and can bring plenty of body and bitterness. Quality varies enormously, just as it does with Arabica. Robusta grows at lower altitudes and much more quickly, it's naturally high caffeine acts as a repellent for pests making the plant much more robust (hence the name). As the industry changes it's not uncommon to see specialty robusta.
Variety (varietal) or cultivar
The genetic type of the coffee plant. Think Bourbon, Typica, Caturra, SL28, Catuai or Pink Bourbon. Varieties can influence flavour, plant characteristics and how coffee grows, but they don't guarantee a particular tasting note.
Gesha (Geisha)
A variety famous for some exceptionally floral, tea-like coffees, particularly those associated with Panama. It can command eye-watering prices due to the rarity of the varital, but the name alone doesn't guarantee a brilliant cup.
Single origin
Coffee from a stated geographical source, which might mean a country, region, farm or even a particular lot. The term isn't a precise guarantee of how small or traceable that source is.
Single estate
Coffee attributed to one estate or farm. More specific than simply naming a country, though the level of traceability still depends on the producer and supply chain.
Blend
Coffee combining beans from multiple origins, varieties or lots. A good blend is built to achieve a particular flavour and balance, not to hide bad coffee.
Green coffee
The unroasted beans that arrive at a roastery. Green coffee is usually pale green or yellowish and smells nothing like the finished cup, way more grassy, sometimes a little funky.
Lot
A defined batch of coffee separated for identification, processing, traceability or sale. A lot might represent a farm, harvest, processing experiment or smaller selection of coffee.
Terroir
The combination of geography, climate, soil and growing conditions that influences how a coffee develops. It's one part of the story, alongside the plant, farming and processing.
Altitude
The elevation at which coffee grows. It can influence ripening and cup characteristics, but higher isn't automatically better. Farming, variety, climate and processing matter too.
Harvest
The period when ripe coffee cherries are picked. In many origins, harvesting happens over several months rather than all at once.
Traceability
How well you can follow a coffee back through its supply chain, ideally to the people and places that grew and processed it.
Producer
The person, family or organisation responsible for growing coffee, and sometimes processing it too. They're not simply a name on the bag.
Importer
The business that sources green coffee and brings it into the roastery's market. Importers can play a significant role in building long-term relationships with producers.
Processes: what happens before roasting?
Process is how freshly picked coffee cherries become stable, dried green coffee ready for milling, export and roasting. It's a major influence on flavour, although the result also depends on the coffee itself and how it's grown.
A quick warning: descriptions such as fruity, clean and fermenty are tendencies, not promises. Two coffees processed in the same way can taste completely different. Experimental process names can also mean slightly different things from one producer to another.
One final thing about processing: coffee is still a seed at the centre of all this. Processing changes its flavour, but doesn't make the variety, growing conditions or quality of the original cherry irrelevant.
Washed (wet process)
The cherry skin and pulp are removed, and the sticky mucilage is broken down and removed through fermentation, washing or a combination of methods. The beans are then dried.
What you might taste: Clean, clear flavours, bright acidity, florals, citrus and a stronger sense of the coffee's underlying character.
In short: Less fruit left around the bean during drying. Not necessarily less sweetness.
Natural (dry process)
The whole cherry is dried with the fruit still around the seed. This takes careful management to avoid uneven drying, mould and unwanted flavours.
What you might taste: Berry fruit, tropical fruit, wine-like notes, sweetness and a fuller texture.
In short: Fruit-forward, sometimes beautifully so. Sometimes a bit too much of a good thing.
Honey process
The outer skin is removed, but some of the sticky mucilage is left on the bean as it dries. Despite the name, honey isn't necessarily involved.
What you might taste: Sweetness, rounded fruit, caramel-like flavours and a balance between clean and fruit-heavy character.
In short: A name for the sticky layer, not an instruction to expect honey in your mug.
Anaerobic fermentation
Coffee cherries or depulped coffee ferment in a controlled environment with little or no oxygen, often in sealed tanks. The coffee can subsequently be washed, honey processed or dried as a natural.
What you might taste: Intense fruit, unusual aromatics, spice, wine-like flavours or pronounced fermentation character.
In short: A fermentation condition, not one single finished processing method.
Carbonic maceration
A technique associated with winemaking in which whole cherries are placed in a carbon-dioxide-rich environment. It can encourage distinctive fermentation and flavour development.
What you might taste: Vivid fruit, floral aromas and wine-like character.
Pulped natural
The cherry skin and pulp are mechanically removed, but much of the mucilage remains during drying. Commonly associated with Brazil, it's closely related to honey processing, although terminology and exact methods vary.
What you might taste: Nutty sweetness, chocolate, body and ripe fruit.
Wet-hulled (Giling Basah)
A method strongly associated with Indonesia. The parchment surrounding the bean is removed while the coffee is still relatively wet, before final drying.
What you might taste: Full body, earthy or herbal character, spice and sometimes savoury notes.
The experimental stuff
These terms appear on more and more coffee bags. They're worth understanding, but a fancy process name isn't a quality score.
Co-fermentation
Coffee is fermented alongside an additional ingredient, such as fruit, or under conditions designed to influence flavour. The exact method matters: the term is used inconsistently across the industry.
Infused coffee
Coffee processed with added flavouring ingredients or extracts. The distinction between infusion, co-fermentation and other experimental methods isn't always clear from the label, so ask the producer or roaster what actually happened.
Thermal shock
A process involving rapid temperature changes, often using hot and cold water at particular stages. Producers use it to influence fermentation or flavour development. The details vary, so the name alone doesn't tell you the full recipe.
Lactic fermentation
A process designed to encourage lactic acid bacteria activity. Depending on the protocol, it can produce creamy impressions, rounded acidity and distinctive fermented flavours.
Yeast-inoculated fermentation
Selected yeast strains are introduced to help guide fermentation. This is a way of influencing the process, rather than a single processing method.
Extended fermentation
Coffee is fermented for longer or under more controlled conditions than a producer's usual protocol. Longer isn't automatically better: the outcome depends on the environment, temperature, microbes and timing.
Double fermentation
Two fermentation stages are used. The conditions can differ between stages, and the term can describe several distinct protocols.
Double anaerobic
Usually refers to two anaerobic fermentation stages, although producers may use the term differently. Check how the coffee was actually processed.
Koji fermentation
Uses Aspergillus oryzae, a mould used in foods such as miso and sake, as part of an experimental coffee process.
Barrel-aged coffee
Coffee is exposed to a barrel environment, often one previously used for wine or spirits. The precise method varies, and flavour can come from the wood, residual aromas or fermentation conditions.
Pre-fermentation drying
Cherries or coffee are partially dried before a subsequent fermentation stage. This changes the conditions under which fermentation happens.
Wet fermentation
Fermentation takes place with water present, commonly in washed processing. It describes the conditions rather than one universal recipe.
Dry fermentation
Fermentation without the addition of water, often used in traditional processing or controlled experimental protocols. It doesn't automatically mean the same thing as natural processing.
Aerobic fermentation
Fermentation in the presence of oxygen.
Anoxic fermentation
Fermentation in an environment with virtually no oxygen. The term is often used alongside anaerobic fermentation.
Black, red, yellow and white honey – Labels sometimes used to describe how much mucilage is retained or how the coffee is dried. There is no universal colour scale across all producers.
The Decaffeination Process(es)
The process of removing most of the caffeine from green coffee while retaining as much flavour as possible.
Swiss Water: A water-based decaffeination method using solubility and filtration.
Sugarcane or EA process: Uses ethyl acetate, which can be naturally produced from sugarcane-derived ethanol, to remove caffeine.
CO₂ process: Uses pressurised carbon dioxide to extract caffeine selectively.
Roasting: turning green beans into coffee
Roasting
Applying heat to green coffee to create the aromas, flavours, colour and structure we recognise in roasted beans.
Roast profile
The record and plan for how a coffee is roasted, including time, temperature, heat input and airflow.
Charge temperature
The roaster's indicated temperature when a batch is introduced. The meaning of that reading depends on the machine and probe.
First crack
A series of audible pops as pressure builds inside the beans and their structure changes during roasting. A key milestone for roasters.
Development time
The time between first crack beginning and the end of the roast.
Development ratio
Development time expressed as a percentage of total roast time. Useful for comparing roasts, but not a universal quality target.
Rate of rise (RoR)
How quickly a measured roast temperature is increasing over time. Roasters use it to understand the roast's momentum.
Drop temperature
The recorded temperature when the beans are released from the roaster.
Cooling
Rapidly bringing roasted beans down to a stable temperature to stop the roasting process progressing unnecessarily.
Roasting: How the roast changes the flavour of the coffee
Light roast
Generally aims to preserve more of the coffee's original character and acidity. Can be delicate, floral and sweet, but can also taste sour or underdeveloped if poorly roasted.
Medium roast
A broad category balancing origin character with roast-developed sweetness and body.
Dark roast
More roast-developed flavours, often including bittersweet chocolate, smoke or toasted notes. Darker doesn't automatically mean stronger or more caffeinated.
Underdeveloped
A roast where desirable flavours haven't developed sufficiently. It can taste sharply sour, grassy or hollow.
Baked
A term for coffee perceived as flat, muted or lacking sweetness and vibrancy, sometimes associated with an overly drawn-out roast. The diagnosis isn't always straightforward.
Scorching and tipping
Roast defects associated with excessive local heat, appearing as burnt or damaged areas on beans.
Degassing
The release of gases, especially carbon dioxide, from roasted coffee. Coffee needs some time after roasting to settle, particularly before espresso brewing.
Resting
Allowing roasted coffee time to settle before brewing. The ideal period depends on the roast, coffee and brewing method.
Freshness
A combination of factors including roast date, storage, oxygen exposure and the coffee's stage of degassing. Freshly roasted isn't always immediately ready to brew.
Tasting: how to talk about coffee without sounding insufferable
Cupping
A standardised way of preparing and tasting coffees so they can be compared fairly. Coffee is ground, steeped in hot water and assessed for aroma, flavour, acidity, body and other qualities.
Acidity
The lively, bright quality of coffee that can resemble citrus, apples, grapes or other fruit. Good acidity makes a cup feel alive. It isn't the same as sourness.
Sourness
A sharp, unpleasant or unbalanced acidic taste. It can be caused by under-extraction, although roast profile and the coffee itself matter too.
Sweetness
The impression of sweetness in the cup, often described through associations with caramel, honey, ripe fruit or chocolate. It doesn't necessarily mean sugar has been added.
Bitterness
A bitter taste that can be pleasant in balance, like dark chocolate, or unpleasantly harsh. Roast level and extraction can both influence it.
Body
How heavy or light a coffee feels in your mouth. Think tea-like versus creamy or syrupy.
Clarity
How distinctly you can pick out the different flavours in a coffee.
Complexity
The range and interaction of flavours and aromas you perceive.
Clean cup
A coffee without obvious unwanted or muddy flavours that distract from its character.
Balance
How well the different qualities of a coffee work together. Acidity, sweetness, bitterness and body don't have to be equal.
Aftertaste
The flavour that remains after swallowing.
Tasting notes
Descriptive references to flavours and aromas, such as peach, chocolate or jasmine. They aren't necessarily ingredients in the coffee.
Aroma
What you smell in the coffee, both dry and after brewing.
Fragrance
The smell of ground coffee before water is added.
Mouthfeel
The tactile sensation of coffee in the mouth, including weight, texture and astringency.
Astringency
A drying, puckering sensation, similar to strong black tea. It isn't a flavour in itself.
Extraction
The process by which water dissolves flavour compounds and other soluble material from ground coffee.
Under-extraction
Too little desirable material has been extracted, often resulting in sour, thin or undeveloped flavours.
Over-extraction
An informal term for a brew that tastes excessively bitter, drying or harsh. Those flavours can have other causes, so don't blame extraction for everything.
Strength
How concentrated the dissolved coffee material is in your drink. A strong coffee isn't necessarily more extracted or better.
TDS (total dissolved solids)
A measure of the concentration of dissolved material in brewed coffee, usually expressed as a percentage.
Extraction yield
The proportion of the original dry coffee mass that has dissolved into the brew. Useful in coffee science, but you don't need to calculate it to make a nice cup.
Brewing: the bits that actually affect your cup
Brew ratio
The amount of coffee compared with the amount of brewing water. A ratio of 1:16 means 1g of coffee for every 16g of water.
Dose
The weight of dry coffee used for a brew.
Grind size
How finely or coarsely the beans are ground. Finer grinding generally speeds extraction; coarser grinding generally slows it, although the result depends on the brewer and the coffee.
Grind distribution
How consistent the particles are after grinding. A grinder producing lots of very fine particles alongside large chunks can make extraction less predictable.
Bloom
The first addition of water in many filter recipes, allowing trapped gas to escape before the main pour.
Pour rate
How quickly water is poured over the coffee.
Agitation
Movement caused by pouring, stirring or swirling. It can help water contact the grounds more evenly, but excessive agitation may cause problems in some brewers.
Drawdown
The time it takes water to drain through a filter bed.
Bypass
Water added directly to brewed coffee rather than passing through the grounds. Used to adjust strength without further extracting the coffee.
Immersion
Brewing where the coffee grounds sit in water for a period, as with a French press or many AeroPress recipes.
Percolation
Brewing where water flows through the grounds, as with a V60 or automatic filter machine.
Channeling
Water finding easier routes through a coffee bed instead of flowing evenly. Particularly important in espresso.
Puck
The compressed bed of ground coffee inside an espresso portafilter.
Dialling in
Adjusting grind size, dose, yield, temperature or other variables until the coffee tastes good.
Water hardness
The concentration of minerals such as calcium and magnesium in water. It influences extraction and can affect equipment.
Alkalinity
Water's capacity to neutralise acids. It affects how the acidity of coffee comes across.
Filtered water
Water treated to remove certain impurities or alter its composition. A filter doesn't necessarily make every water suitable for coffee.
Brew temperature
The temperature of the water used to brew. Hotter water generally extracts more quickly, but grind, roast and method all influence the result.
Coffee-to-water ratio
Another way of describing brew ratio. In filter coffee, the ratio usually refers to dry coffee and the water poured in, not the final beverage weight.
Brewing methods: which bit of kit does what?
V60
A conical pour-over brewer with spiral ribs and a large opening. It gives you control over pouring and can produce a clear, expressive cup.
Orea
A flat-bottom pour-over brewer designed around a different flow pattern from a V60. Its shape, filter choice and recipe all influence the result. There are different Orea models, so check which one you're using.
French press (cafetière)
Coffee steeps in water before being separated by a metal mesh plunger. Expect more oils and texture than from a paper-filtered brew.
AeroPress
A versatile brewer that combines immersion and pressure. It's portable, forgiving and can make everything from a concentrated cup to a longer coffee.
Moka pot
A stovetop brewer that pushes hot water through coffee using steam pressure. It makes a concentrated coffee, but it's not quite espresso.
Espresso machine
Forces hot water through finely ground coffee under pressure. Produces a concentrated drink that forms the base of flat whites, cappuccinos, lattes and other café favourites.
Automatic filter machine
Heats and distributes water over coffee automatically. A good machine can make consistently excellent coffee without requiring a gooseneck kettle or a dramatic pouring ritual.
Cold brew
Coffee steeps in cool or room-temperature water over several hours. It can be served ready to drink or made as a concentrate for dilution.
Cezve or ibrik
A small pot used to make Turkish-style coffee with extremely fine grounds. The coffee is heated in water and served unfiltered, allowing the grounds to settle.
Equipment: your coffee kit explained
Burr grinder
Uses two grinding surfaces to break beans into particles. Generally the best starting point for consistent home brewing.
Blade grinder
Chops beans with spinning blades. Often less consistent than a burr grinder.
Hand grinder
A manual burr grinder. Good models can produce excellent results without taking up much space or costing as much as an electric grinder.
Brew scale
A scale accurate enough to weigh coffee and water. It removes much of the guesswork.
Gooseneck kettle
A kettle with a narrow spout that gives you more control over pouring.
Thermometer
Useful for checking water temperature if your kettle doesn't have temperature control.
Paper filter
Traps most of the coffee oils and fine particles, usually producing a cleaner cup.
Metal filter
Allows more oils and fine particles through, often producing a fuller-bodied drink.
Portafilter
The handle and basket that hold ground coffee in an espresso machine.
Tamper
Compresses the coffee evenly in the portafilter.
Distribution tool
Helps redistribute grounds in an espresso basket before tamping. Different tools work in different ways.
Knock box
A container for disposing of used espresso pucks.
Refractometer
Measures how much light bends through a sample, allowing dissolved solids to be estimated. Useful for people measuring extraction, but not a requirement for good coffee.
Coffee canister
An airtight container for storing beans. Keep coffee away from excessive heat, light, moisture and oxygen.
Water filter
A device that alters water quality or composition. The right choice depends on your incoming water and the brewer.
The coffee industry: useful words to know
Specialty coffee
Coffee assessed and valued for its quality, distinctiveness and the people and practices behind it. The industry has used formal scoring systems, but the term is also used more broadly.
Fair trade
A term associated with particular trading standards and certification schemes. It isn't interchangeable with direct trade or a guarantee of a particular cup quality. Just because a farm doesn't carry this certification, doesn't mean they are not practicing fair trade, or treating their employees properly, certifications often involve large sums of money paid in annually and take money out of farmer's pockets.
Direct trade
A phrase used for sourcing relationships involving direct communication or purchasing between roasters and producers. It has no single universal definition and isn't automatically a certification.
Certification
A formal scheme with defined standards and auditing, such as organic or Fairtrade certification.
Organic
Coffee grown under the requirements of an applicable organic standard and certification scheme. Requirements vary by market. Much like the Fair Trade certification, this is a scheme farmers must pay into. This certification isn't available in every coffee producing country. We aim to work with farmers and importers that are commited to sustainable agriculture.
Sustainability
A broad term covering environmental, social and economic considerations. Ask what a business actually does rather than taking the word on the bag as proof.
Micro-lot
A relatively small, separately identified lot of coffee. There is no universal size limit.
Cup score
A numerical assessment of coffee using a particular scoring framework. Scores can help with comparisons, but they're not a substitute for your own palate.
Green grading
Assessing green coffee for defects, size, density and other characteristics before roasting.
Specialty coffee shop
A café that typically puts emphasis on coffee quality, brewing, sourcing or preparation. The label alone doesn't tell you whether the coffee will taste good.
And that's the glossary. It's a starting point, not a set of rules. The best reason to learn any of this is to understand what you're drinking, make a better cup and work out what you actually like.