Glossary

The Agtron is a specially modified spectrophotometer that reads the color of roasted coffee, and a higher score means a lighter roast. Coffee Review uses the M-Basic, or Gourmet, scale and reports two numbers for each coffee, whole bean before the slash and ground after it. It calls an average above 80 light, 60-70 medium and 40-50 dark. Different scales and meters exist, so only compare numbers from the same one.

See

Altitude is the height at which coffee grows, written in meters above sea level (masl). Arabica is usually grown at about 1,200 to 1,500 m, though some plantations sit anywhere from sea level to 2,800 m. Robusta tolerates lower ground, around 400-700 m. Height also changes disease pressure. Coffee leaf rust develops more slowly on cooler, higher plantations.

See Coffee Rust · Terroir

A beneficio is a station where harvested cherries first arrive, and the word is widely used in Central America. A wet beneficio pulps, ferments and washes the coffee. A dry beneficio is a mill that hulls it. Green Coffee Collective lists it alongside wet mill and washing station as names for the same kind of place.

See Washed · Wet Milling (Pulping) · Wet Mill · Washing Station · Dry Mill

Roasters blend to balance sweetness, acidity and body, to hold a steady flavor when one component runs short, and to hit a price while keeping pricier coffees in meaningful amounts. Royal Coffee suggests starting with two to four coffees and notes that parts under about 25% have little effect, especially in espresso. Some roasters blend green coffee before roasting, others roast each coffee separately and blend after.

See Single Origin

Bloom is when you pour a little hot water on the grounds and let them bubble before brewing. The bubbles are CO₂ escaping, and an energetic, domed bloom is a sign the coffee is fresh. Older coffee blooms weakly or not at all.

See Degassing

Chipped and broken beans become far more common when coffee is hulled below about 12% moisture, because over-dried beans turn brittle and break in the huller. Mills sort them out by size, density and color.

See Screen Sizing · Dry Milling

A burr grinder crushes coffee between two grinding surfaces, and the gap between them sets the particle size. That gives more uniform particles than a blade grinder, which chops to a wide range of sizes, and burrs also heat the coffee less through friction. Ceramic burrs are extremely hard and do not corrode, and stainless steel is durable too.

See Grind Size

Bypass is water that finds its way into the final brew without having passed through the bed of ground coffee. It can be deliberate, such as fresh water added after brewing, or accidental. Deliberate bypass is generally considered good, and accidental bypass hurts extraction. An Americano, which is espresso topped up with hot water, is a familiar example.

See Ratio

The C price comes from the Coffee C futures contract on ICE Futures U.S. Each contract covers 37,500 pounds and is quoted in cents per pound. Coffee is graded, including by cup testing, and better coffee trades at a premium and inferior coffee at a discount to the exchange's basis coffees. Delivery origins carry set adjustments, so Colombian or Kenyan coffee can be delivered at a premium and Brazilian at a discount.

See Differential

Caffeine is an alkaloid in the methylxanthine family. In the brain it blocks adenosine receptors, which delays the drowsiness adenosine would cause. A 6-ounce cup of coffee typically holds 50-175 mg, depending on the bean, the roast and how it is prepared. Robusta carries more than arabica, about 2.7% against 1.5% in one source, and caffeine hardly changes in the roaster.

See Decaf

Cascara is the dried skins and pulp of the coffee cherry, left over once the seeds are taken out, steeped as a tea. It is traditionally consumed in Yemen and Ethiopia and tastes fruity and floral. A typical brew is about three tablespoons of flaked cascara in 10-12 ounces of hot water for four minutes, or in cold water for 12-16 hours. Its caffeine is similar to black tea.

See Qishr · Natural · Washed

Chaff is the silverskin that loosens and separates as heat expands the bean. Roasters collect it in a chamber or cyclone, and a build-up is a fire risk in an enclosed roaster, so the collector should be emptied between sessions. A large deposit after a roast is normal.

See Silverskin

Channeling happens when water finds a shortcut through the puck instead of flowing evenly through the whole bed. Gaps from poor distribution, cracks from uneven tamping, clumps, too little coffee in the basket, stale coffee or a grind that is too coarse can all start it. The channel gets over-extracted while the rest is barely extracted, so you taste sour and bitter at once.

See Grind Size · Dial In

The coffee cherry is the fruit of the coffee plant, and what we call beans are its seeds. From outside in there is a skin, a sugary sticky layer of mucilage, a hard parchment shell and a thin silverskin on the seed. Red is the usual ripe color, though some varieties ripen yellow.

See Selective Picking · Strip Picking · Natural · Washed · Mucilage

Roasted chicory root has a long history as a coffee substitute and additive. Prussia's ban on coffee imports in 1766 pushed people toward substitutes, and chicory was a common stand-in or adulterant in Napoleonic-era France. In New Orleans the habit stuck after Civil War naval blockades cut off the port, and it is still mixed into Indian filter coffee and in other places such as Turkey and Spain.

See Kaapi

Chlorogenic acids are compounds formed from hydroxycinnamic acids and quinic acid. They make up roughly 4-12% of the dry weight of green coffee, depending on species and origin. They do not survive heat well, and at dark roast levels more than 80-90% can be gone, partly turned into lactones that add bitterness. They contribute to antioxidant capacity, acidity and bitterness.

See Trigonelline

The coffee berry borer is a beetle native to central Africa. Females usually bore into the cherry through its central disc, dig galleries into the seed and lay eggs there, and one fruit can hold up to 100 beetles. Egg to adult takes about 24-45 days. Called the most harmful insect pest of coffee worldwide, it does best in shaded, humid parts of plantations. Control includes birds, parasitoid wasps and the fungus Beauveria bassiana.

See Shade-Grown

Coffee berry disease is caused by the fungus Colletotrichum kahawae and attacks arabica, mostly the green berries, which are most vulnerable four to 14 weeks after flowering. It leaves dark, sunken spots that can blacken the whole berry, and losses can reach 80%. It occurs only above 1,000 m. Resistance comes from the arabica variety Rume Sudan and the Timor Hybrid, and from varieties bred from them such as Catimor and Ruiru 11.

See Catimor · Coffee Rust

Coffee leaf rust is caused by the fungus Hemileia vastatrix, which can only live on coffee plants. It shows as yellow-orange, powdery growths on the underside of leaves, and heavy infection strips leaves from the plant and cuts yield and quality. The spores need free water on the leaf and mild temperatures. Higher, cooler plantations see it develop more slowly. Resistant cultivars are the most durable defense.

See Catimor · Coffee Berry Disease (CBD) · Altitude

Commodity coffee is the commercial end of the market, priced against the C futures contract. Royal Coffee describes scores of 70-79.9 on the 100-point scale as commercial or commodity grade. Commercial blends aim for steady consistency, while specialty coffee can change noticeably from one harvest to the next. Buyers still negotiate differentials above or below the C price for quality.

See C-Price · Differential · Specialty Coffee · Past Crop

In a coffee cooperative, members typically bring their cherries to a shared wet mill, and the cooperative processes and sells the coffee together. In Kenya one society can own several wet mills, as with four mills near Nyeri, and sells at the weekly auction or directly to roasters. Fairtrade-certified coffee is normally exported by cooperatives on behalf of farmers' organizations.

See Washing Station · Fair Trade · Estate

Crema is a layer of dense foam that sits on top of an espresso. It is made of emulsified oils from the ground coffee turned into a colloid. Water under very high pressure dissolves more carbon dioxide, the gas produced during roasting, and that gas forms the foam. It is lighter in color than the dark body of the drink and is a feature of espresso in particular.

See

A crop year is a 12-month period that starts in the producing country's harvest month. Brazil's typically begins in April, Colombia's in October and some East African origins' in July, so a 2023/24 Colombian lot and a 2023/24 Brazilian lot can be different ages. Do not confuse it with the ICO coffee year, which runs from 1 October to 30 September for statistics.

See Past Crop

Cupping is the practice of observing the tastes and aromas of brewed coffee, judging things like body, sweetness, acidity, flavor and aftertaste. The long-standing SCA protocol uses 8.25 g of coffee to 150 mL of water, roughly 1:18, with the coffee ground just before. You wait four minutes, break the crust with a spoon, then slurp, which aerates the coffee and spreads it across the palate. The SCA introduced new Coffee Value Assessment forms in 2023 to replace its legacy cupping forms.

See

Decaf is made by taking caffeine out of green coffee before roasting. Methods include solvent rinsing with ethyl acetate or dichloromethane, the water-only Swiss Water process, and supercritical CO₂. US FDA standards call for at least 97% of the caffeine to be removed, and the EU standard is 99.9% caffeine-free by mass.

See Swiss Water Process · CO2 (Supercritical) Decaffeination · Methylene Chloride (Solvent) Decaffeination · Sugarcane / Ethyl Acetate (EA) Decaffeination

Defects are split into primary, or type one, which significantly affect the cup, and secondary, or type two, which have a minor effect. Full black, full sour and dried cherry are the main primary defects that mills remove. Under SCA standards a 350 g sample is graded, and any category one defect disqualifies a coffee from specialty grade. Preparation grades differ by country, and El Salvador's European Preparation allows six defects per 300 g against twelve for American Preparation.

See Triage

Roasting leaves CO₂ in the bean, and it escapes slowly afterward. That is why vacuum-packed coffee has to de-gas for several days before it is sealed, and why bags with pressure-relief valves allow faster packaging. Most roasters recommend resting espresso for at least five to ten days. Lighter roasts degas more slowly than darker ones, and ground coffee loses freshness much faster than whole beans.

See Bloom

Development is the phase of a roast from first crack to the end. Roasters treat it as the stage where most flavor decisions are made.

See First Crack

Dialing in means adjusting grind, dose and other brew variables to get a particular coffee extracting well. A finer grind exposes more surface area, so a grind that is too fine tastes bitter and over-extracted while one that is too coarse gives a weak cup. In espresso, water temperature, pressure and tamping also affect quality.

See Grind Size · Extraction

A differential is the premium or discount applied to a specific green coffee above or below the C-market price, in US cents per pound. It lets buyer and seller agree the quality premium for a lot without fixing the full price in advance. The differential stays fixed while the base price moves with the market. Negative differentials are rare in specialty but exist for lower-grade material.

See C-Price · Specialty Coffee

Direct trade is a sourcing approach in which roasters build direct relationships with the farmers and processors they buy from. There is no single set of standards, so practices vary by company. The lack of third-party accountability is a frequent criticism, though some roasters have their practices audited by an independent party.

See Fair Trade · Cooperative

Dry milling starts by taking off the remaining parchment, dried mucilage or dried fruit by a rubbing or tearing action in a huller. The coffee is then cleaned, sorted by size, density and color, and graded. It is typically done at a dedicated plant in the producing country shortly before export. Hulling coffee drier than about 12% moisture sharply raises the number of chipped and broken beans.

See Dry Milling · Screen Sizing · Density (Gravity Table) Sorting · Milling

An estate coffee comes from a single, named farm or plantation rather than a blend of many smallholders' harvests. The label implies one team manages the property from growing through to export, though how strictly the word is used varies by origin. Most coffee farms are small. Holdings under two hectares make up about 80% of the world's coffee farms and produce about 60% of the crop.

See Single Origin · Cooperative · Micro-lot

Extraction is the share of the grounds' weight that ends up dissolved in your cup. A widely used target is about 20%, within a band of 18-22%. Below that, coffee tends to taste sour and under-extracted, and above it bitter. Grind size, contact time and water temperature all move it.

See TDS

Fairtrade coffee comes with a minimum price that works as a floor, so it only matters when the market falls below it and farmers still earn more when prices rise. Cooperatives also receive a Fairtrade Premium on top, which they decide how to invest. Fairtrade International sets the standards and its subsidiary FLO-CERT inspects producers. Prices are reviewed on a four-year cycle, so check the current figures before quoting them.

See Direct Trade · Cooperative · Organic

Fermentation is the microbial breakdown of fruit compounds, and it shapes the flavor of washed, honey and natural coffees. In the washed method it loosens the mucilage and typically runs about 12 to 36 hours, with millers judging the end point by touch, when the parchment turns gritty. Mechanical demucilagers skip it and avoid the 2-3% weight loss fermentation causes.

See Washed · Honey · Anaerobic Fermentation · Mechanical Demucilage

First crack is the cracking sound beans make during roasting at around 196 °C. By then the beans have expanded significantly and lost much of their moisture. It marks the beginning of a very light roast and the start of the development phase.

See Development

Flotation separates the harvest in water by density. It sorts by weight, not by ripeness. What floats is leaves, twigs, cherries dried on the tree, overripe fruit and underweight beans. Unripe cherries and stones generally sink, so flotation does not remove them.

See Cherry Flotation Sorting · Washed

A fly crop is a smaller secondary harvest that follows the main season. It is most associated with Kenya, where it typically falls between April and June while the main harvest peaks from October to February. Lots tend to be smaller and sometimes lower in quality, though that varies by farm and season. Where the name comes from is unclear.

See Main Crop · Mitaca

Green coffee is the seed once the fruit and parchment are gone, before it meets the roaster. It keeps far better than roasted coffee. One source puts storage in a climate-controlled room at about 12-18 months before quality loss becomes noticeable.

See Dry Milling · Dry Mill

Grind size decides how much surface area the water can reach. Finer grounds expose more surface, so methods with longer contact time need coarser grounds. A grind that is too fine tastes bitter and over-extracted, and one that is too coarse gives a weak cup. Uniformity matters too, and burr grinders produce more even particles than blade grinders.

See Burr · Dial In

In honey processing the skin is removed but the mucilage stays on the parchment through drying, and the washing step is skipped. Yellow, red and black honey are named for how much mucilage remains, and drying takes about 8-10 days for yellow, 12-15 for red and around 30 for black. It uses less water than washed processing and gives a mellow, sweet cup.

See Honey · Red Honey · Washed · Natural

Intercropping is growing two or more crops at once in the same field. It can raise or steady yields, and a legume intercrop can supply nutrients such as nitrogen. In traditional coffee polyculture, farmers grow food, fuel and medicinal plants among the coffee, which helps when prices fall.

See Shade-Grown · Shade Trees

Filter kaapi is brewed by percolation in a stainless steel filter of two stacked cups, with boiling water poured over pressed, finely ground coffee. Traditionally the coffee is a dark roast of washed arabica or peaberry, often blended with 10-20% chicory. The decoction is mixed with hot milk and sugar, once jaggery or honey and since the mid-1900s often white sugar, and served in a tumbler and dabarah that are poured between to cool and froth it.

See Chicory

Kopi is the Malay word for coffee, also used in Indonesian. In Singapore and Malaysia it names a local style that came from Hainanese coffee shops in the early to mid 1900s. Traditionally it uses Robusta, and plain kopi means coffee with sugar and condensed milk. Kopi O is black with sugar, and kopi C has evaporated milk. In Indonesia, kopi tubruk is a different thing, grounds with hot water poured straight into the glass with no filter.

See Kaapi

The main crop is an origin's principal harvest. Most coffee-growing countries have one major harvest a year, while a few have two. Timing varies. Kenya's main harvest peaks from October to February, and Colombia's main harvest runs October to December, with a smaller mitaca crop later.

See Mitaca · Fly Crop

A micro-lot is a small, carefully separated batch of green coffee that stands apart from a farm's regular production, often from a single plot. There is no agreed size. One Brazilian estate calls up to 40 bags of 60 kg a micro lot. In countries of tiny farms the idea looks different, because a micro lot there may pool coffee from several nearby members.

See Nano-lot · Single Origin · Estate

Dry milling covers hulling, optional polishing, cleaning, sorting and grading. It usually happens at a dedicated plant shortly before export. In Indonesian wet-hulled processing, the parchment is taken off while the bean is still wet, which turns the order around.

See Dry Milling · Screen Sizing · Dry Mill

Mitaca is Colombia's secondary crop, picked in the first half of the year. Colombia flowers twice a year, which gives it a main crop and a smaller secondary one. The mitaca can make up to 45% of the country's output in a calendar year. Sources date it differently, from April-June to January-June, since timing varies by region.

See Main Crop · Fly Crop

Mucilage is the sticky, pectin-rich layer that surrounds the seed once the skin is off, between the pulp and the parchment. In washed coffee it is removed by fermentation and washing or by a machine, in honey coffee some is left on to dry with the seed, and in naturals the whole cherry dries with it. Fermentation to loosen it usually runs about 12 to 36 hours.

See Washed · Honey · Natural · Mechanical Demucilage

A nano-lot is an exceptionally small parcel of green coffee. Green Coffee Collective describes it as typically below 60 kg, and Perfect Daily Grind calls it very like a micro lot but smaller. One Brazilian estate says its nano lots are usually one or two 60 kg bags. Sizes differ between sellers.

See Micro-lot · Single Origin

Natural, or dry, processing is the oldest method. The whole fruit is cleaned and dried in the sun on patios or raised beds and turned by hand or rake, which can take about four weeks to reach 12.5% moisture. It needs dry weather. About 90% of Brazilian arabica and nearly all robusta are processed this way. Green Coffee Collective describes the cup as heavy in body and fruit-forward.

See Natural · Washed · Honey

Organic coffee is produced without artificial chemical substances such as synthetic pesticides, herbicides and fertilizers. Under the US rules, land that has had no prohibited substances for three years before harvest can qualify, and the USDA's National Organic Program oversees the label. Farm fertilizer has to be organic, with examples such as manure, coffee pulp and compost. Internationally, the Codex Alimentarius sets guidelines. An organic label is not a statement about healthiness.

See Fair Trade · Shade-Grown

Parchment is the paper-like shell that surrounds the green bean once the fruit skin is gone, beneath the mucilage. It stays on through drying and is removed by hulling at the dry mill, just before grading, sorting and export.

See Dry Milling · Wet Milling (Pulping) · Mucilage

Past crop is green coffee that is no longer considered current or new crop. There is no fixed cutoff, but it generally means 18 to 24 months from harvest. It tends to lose brightness and acidity, its color moves from green toward yellow or pale, and it is usually sold at a discount, mostly into commercial blends. It is different from intentionally aged coffee such as Monsooned Malabar, where the aging is controlled.

See Crop Year

A peaberry forms when only one seed in the cherry is fertilized and develops, so it is not flattened against a partner and comes out oval. Sources quote a small share of beans, roughly 5-15% depending on the source. Producers often separate peaberries because they roast a little differently. They are especially associated with Tanzania. Claims that they taste better are common but thinly evidenced.

See Density (Gravity Table) Sorting · Screen Sizing

Pulp is the outer fruit that pulping removes from the seed, while the sticky mucilage lies closer to the parchment. It adds up to a lot of material. A tonne of fresh cherry yields only about 200 kg of green arabica. Dried skins and pulp can be steeped as cascara.

See Washed · Mechanical Demucilage · Cascara · Pulping

Pulping takes the fruit off the seed before drying, using disc, drum or screen pulpers. The harvest is usually cleaned first by winnowing, screening and water separation. What is left is the seed in its parchment with mucilage still stuck to it, which washed processing then removes and honey processing partly keeps.

See Washed · Mechanical Demucilage · Wet Milling (Pulping) · Honey

A Q Grader is a professional coffee taster licensed through a six-day course and exams. Until October 2025 the Q program was run by the Coffee Quality Institute, whose format had three days of theory and practice, then 20 exams, a certificate valid for 36 months and an in-person calibration every third year. On 1 October 2025 the Specialty Coffee Association took over, and it is rebuilding the license around its Coffee Value Assessment, so details may keep changing.

See Cupping

Qishr is a Yemeni drink made from the dried husks of the coffee cherry, a delicately flavored, tea-like infusion usually flavored with ginger and sometimes cinnamon. Yemenis use husks that other producing countries throw away. From mid-morning on it becomes the usual drink, and since it needs no roasting it is often drunk in place of coffee.

See Cascara

A quaker is a bean that does not brown in the roaster because it lacks the sugars and starches for normal development. Unripe cherries at harvest are the main cause. Quakers are nearly impossible to spot in green coffee, but stand out as pale beans after roasting. They taste dry, papery, faintly peanutty and astringent, with no sweetness. Roasting darker does not help. They cannot be reliably removed before roasting, so commercial operations use optical sorters afterward.

See Density (Gravity Table) Sorting

The Rainforest Alliance is an international nonprofit founded in 1987. Its seal appears only on products from farms that meet its crop standards, which cover ecosystem conservation, protection of wildlife and waterways, reduced agrochemical use and protections for workers and communities. It merged with UTZ in 2018, and its 2020 standard built on both. Critics point out it sets no minimum coffee price.

See Shade-Grown · Fair Trade

Brew ratio is the proportion of coffee to water. For filter coffee, preferred ratios by mass fall around 15-18 parts water to one part coffee, and standard targets run from about 55 g/L to 63 g/L. Espresso is far more concentrated, with about 7 g for a 25 ml shot in the Italian standard, and a double ristretto near 1:2. The SCA cupping standard works out to about 1:18.

See TDS

Second crack is a second round of cracking at around 224 °C, when the beans' structure is brittle and fractures under internal pressure. It marks the start of medium-dark roast territory. Full City is described as beginning at second crack, Vienna in the middle and French near its end, by which point the beans are shiny with oil.

See First Crack

In selective picking, only ripe cherries are picked, individually and by hand. It is labor-intensive and costs more, so it is mainly used for finer arabica. The payoff is that the fruit is more evenly ripe, where strip picking takes everything on the branch at once.

See Strip Picking · Selective Picking · Washed

Shade trees shield coffee from wind, rain and intense sun and can buffer drought, and their leaf litter can return nutrients to the soil. They also compete with coffee for water and nutrients, take upkeep, and keep the air humid enough to favor pests such as the berry borer. Some farms use a single pruned canopy species, such as Inga in Mexico. Rainforest Alliance certification may require as little as 15% shade cover.

See Shade-Grown · Intercropping · Coffee Berry Borer

Shade-grown coffee is grown beneath a canopy of trees, which can mimic natural forest. Farms with more structure host more species. In a Guatemala study, shaded farms had 30% more bird abundance than sun farms. The trade-offs are lower yields, competition for water and nutrients, and humidity that favors pests such as the coffee berry borer.

See Shade Trees · Intercropping · Coffee Berry Borer · Rainforest Alliance

Silverskin is the very thin inner membrane that clings to the bean under the parchment. Polishing at the dry mill can remove what hulling leaves behind, but polishing is optional, so plenty is still shed in the roaster as chaff. One source puts that at about 8 kg per tonne of roasted coffee.

See Chaff · Parchment · Dry Milling

Single origin means coffee grown within a single known geographic origin. That can be one farm, several farms in a country or a country-wide mix, so a country-level label can itself be a blend of that country's coffees. Buyers have pushed labels to be more specific over time, for traceability and distinct lots. There are no universal rules enforcing coffee labels.

See Blend · Estate · Micro-lot

Specialty coffee has long been defined as coffee scoring 80 or above on the SCA's 100-point cupping form. It is also hand-picked and held to a strict defect limit. Any category one defect disqualifies a sample, and one common cap is five defects per 350 g. The SCA has since introduced a Coffee Value Assessment that replaces its legacy cupping forms, so the 80-point line belongs to the older scoring system.

See Commodity Coffee

Specific gravity, or bean density, is what density sorting separates by. A gravity separator vibrates beans over a sloped, air-permeable deck so they sort by density, and it has largely replaced the catador, which blows air up a tall column to lift away light material. Density sorting follows size sorting, which makes it faster and more precise.

See Density (Gravity Table) Sorting · Screen Sizing

In strip picking, all the fruit comes off the tree regardless of ripeness, by hand or by machine. It is fast. A picker can harvest three to four times as much in a day as with selective picking. But it takes unripe fruit too. Brazil has mechanized because its landscape is relatively flat and its fields are huge.

See Selective Picking · Strip Picking · Natural

TDS, or total dissolved solids, is how much dissolved coffee is in your drink, written as a percentage. A refractometer reads it from how the liquid bends light. For filter coffee, common strength targets sit around 1.15-1.50%, depending on the standard. For traditional espresso a target of 8-12% is quoted. Multiply TDS by the drink's weight and divide by the dose to get extraction yield.

See Extraction

Terroir is a French word for the environmental factors that affect a crop, including its growing environment, farming practices and habitat. Those factors cover climate at several scales, soil composition and drainage, the landscape and its elevation, and the plants, animals and microbes nearby. In coffee it is the idea that altitude, soil and climate shape how a coffee tastes.

See Altitude

Triage is the dry-mill sorting step in which defective beans are pulled out before the final lot is packed. It is done by hand or optically. Primary defects such as full black, full sour and dried cherry are the main targets, and secondary defects are removed depending on the lot's specification. How well it is done decides the lot's defect count, and so whether it qualifies as specialty grade.

See Screen Sizing · Density (Gravity Table) Sorting · Dry Milling

Trigonelline is an alkaloid found in coffee, with higher levels in arabica than in robusta. Roasting degrades it into volatile compounds such as pyridines and nicotinic acid, which add to the aroma. It falls at every roast level and drops further in the cup, by roughly 80-94% from green bean to brewed arabica in one review.

See Chlorogenic Acid

Beans are graded on perforated plates measured in sixty-fourths of an inch, and most green coffee falls between screens 12 and 19. Screen 16 is 6.30 mm and screen 18 is 7.10 mm. Beans that fall through the screen for a grade are separated as smaller sizes.

See Screen Sizing · Density (Gravity Table) Sorting

In washed processing the fruit is pulped off the seed first, then the mucilage is removed, by fermenting for roughly 12 to 36 hours and washing or by a machine, before the coffee is dried in its parchment. It uses more water than other methods and the wastewater needs treating. Green Coffee Collective describes the cup as clean, bright and origin-expressive.

See Washed · Natural · Honey · Pulping

A washing station is where many farmers bring their freshly picked cherries to be processed together. It is also called a wet mill, a factory in East Africa or a beneficio in Latin America. Sorting, pulping, fermentation, washing and drying happen there, and how a station manages fermentation and drying is one of the biggest influences on the final cup.

See Washed · Wet Mill · Beneficio

Wet milling is the processing done before drying. In the washed method it means cleaning the harvest, pulping, removing the mucilage by fermentation or by machine, and washing. It uses a lot of water. A small mill has used 2.3 to 23 cubic metres per tonne of cherry, and the effluent is acidic and high in organic matter, so treating it matters.

See Wet Milling (Pulping) · Washed · Mechanical Demucilage · Washing Station