All you need to know about coffee
COFFEE BEANS
Coffee beans grow in the form of cherries, throughout their riping process their color changes from green to red and finally to dark burgundy which signifies full maturity.
A coffee bean is a pip inside the fruit (Coffee Cherry) of the “Coffea” plant. Coffee beans are technically a seed and not beans, they are mainly named as such due to their resemblance to true beans. The Coffee cherry generally contains two seeds. A small percentage of coffee cherries contain a single seed, this is called “Peaberry”.
The coffee tree requires specific growing conditions, moderate temperatures all year round, no frost, and regular rainfall patterns (dry and wet seasons). A temperate, humid, and warm climate, allows for its growing season to last all year round.
There are around 150 different species of coffee trees however only two are important for global coffee production and have an approximately 99% share in it; Arabica Beans (coffea arabica) and Robusta Beans (coffea canephora). Due to their different growing conditions, their taste differs significantly.
Arabica is much smaller, grows at a much higher altitude, and has a low resistance to environmental conditions. The Arabica bean has a fruit/flowers and chocolate “flavor profile”, medium/high acidity, and less caffeine.
Robusta is a much larger tree and grows in lower altitudes, and has a much higher environmental resistance. Robusta Beans have an Earth/cocoa/spices profile and low acidity as well as more caffeine. Robusta is more intense, bitter, and earthy, with notes of chocolate and spices.
Arabica Beans are fruity, juicy, and more delicate, with a higher acidity than Robusta.
ROASTING
The harvested Coffee bean is green with a beany, grassy aroma. In order to provide us with the beverage we all love, coffee beans need to be roasted, a process in which hundreds of new and different aroma compounds are developed.
DRYING STAGE: Beans need to be dried before the actual roasting starts, this typically lasts 4-8 minutes.
BROWNING STAGE: The browning stage starts a reaction (known as the “Maillard reaction”) that is responsible for the browning of the beans. This Maillard reaction reduces sugars and amino acids developing hundreds of different aromas and color compounds known as “melanoids”. In this stage, the roast is slowed down to ensure flavor development.
At the end of the browning stage, the coffee starts to pop, this is called the first crack, and this is when the “development stage” (also named “roasting stage”) starts.
ROASTING STAGE: The roasting stage is the time in which the wanted aroma compounds develop.the length of the “roasting stage” is typically between 15–25% of the total roast time depending on the desired “flavor profile” and roast degree.
ROAST PROFILE: A roast profile is a set of parameters that define how a coffee should be or has been, roasted. The main components of a roast profile are temperature rise (when and how intense are the beans heated), and the reduction of the roast temperature over time. A roast profile varies depending on the bean type used.
In addition to certain factors such as batch size, air flow, bean moisture, drum rotation etc. The origin and type of the bean also influence the taste and determine the type of roasting.
ROAST DEGREE: The roast degree is one of the most important roasting indicators. It is measured by a “color meter” or by tasting. Typically light roasted coffees are more acidic, and dark roasted coffees are more bitter. Fruity flavors are more common on light roasts, whereas roasty and burnt flavors are more common on dark-roasted coffee.
Examples of Light Roast are Cinnamon Roast and New England Roast
Examples of Medium Roast are American Roast and City Roast
Dark Roast examples are Full City Roast, Vienna Roast, French Roast, and Italian Roast
Below is a list of popular roasts ranked from light to dark
. Light City,
. Half City,
. Cinnamon,
. New England Roast
. Regular Roast,
. American Roast,
. City Roast,
. Breakfast Roast,
. City+ Roast,
. Full-City Roast,
. Full-City+ Roast,
. After Dinner Roast,
. Vienna Roast,
. French Roast,
. Italian Roast,
. Espresso Roast,
. Continental Roast,
. New Orleans Roast,
. Spanish Roast.
COFFEE GRINDS:
Coffee beans are ground to allow the flavor to be extracted from the bean in water. The size, quality and freshness of the grind have a significant effect on how a coffee will taste.
When coffee comes into contact with water, different flavor types come out at different times. At first, you get acidic, sharp flavors, but at the end, the flavors get increasingly bitter, that is why grinding fresh and to the correct size makes a huge difference.
PICKING THE CORRECT GRINDING SIZE FOR EACH BREWING METHOD
Extra coarse: Cold Brew Coffee, Cowboy Coffee
Coarse: French Press, Percolator, Coffee Cupping
Medium-coarse: Chemex coffee maker, Clever Dripper, Cafe Solo BrewerMedium, Cone-shaped Pour-over Brewers, Flat Bottom Drip Coffee Machines, Siphon Coffee, Aeropress (with 3+ minute brew time)
Medium-fine: Cone-shaped Pour-over Brewers, Aeropress (with 2-3 minute brew time)
Fine: Espresso, Moka Pot (Stovetop Espresso Maker), Aeropress (with 1 minute brew time)
Extra Fine: Turkish coffee
BREWING
Brewing is the process by which coffee grounds are introduced to water and where the soluble compounds that create the flavors and aromas are dissolved into the water. The final product is called brewed coffee.
The main variables that affect coffee brewing are:
- Grind size and contact time
- Water and water temperature
– Turbulence
– Filtration type
- Brewing Methods
- Water to coffee ratio
Extraction
During the brewing process, different flavors extract at different times. Acidic and fruity flavors are generally extracted first followed by sweet and bitter flavors. The goal is to pull as many desirable flavors from the coffee grounds as possible without pulling out undesirable flavors that can dominate the pleasant ones.
Under, Over, and Ideal Extraction
- Under extraction is sour, sharp, lacks sweetness, and has a quick finish
- Ideal extraction is balanced, sweet, flavorful, and has a lingering finish
- Over-extraction is bitter, astringent, dry, and lacks depth
Brewing techniques that are associated with the different ways of making coffee:
- Boiling: Cowboy Coffee, Turkish Coffee
- Steeping: Cold Brew, French Press, Siphon Brewers, Coffee Bags, Instant Coffee
- Dripping: Pour-Overs, Chemex, Auto-Drip Machine, Percolator
- Pressure: Moka Pot, Aeropress, Espresso Machine, Single Serve Pod Machines
There are also Lesser Known methods such as: Nitrous Coffee, Puerto Rican Coffee, and Vietnamese Phin
GOLDEN RATIO COFFEE
“Golden Ratio Coffee” Is the ideal ratio of coffee ground to water (measured in weight) that produces the perfect balanced coffee.
Each brewing method has its own “golden ratio”
For example, the ideal ratio of ground coffee to water for an Auto-drip Machine is between 1:15 – 1:18, It is 1:16.67 according to SCAE (Speciality Coffee Association of Europe) and 1:18 according to SCAA Golden Cup (Speciality Coffee Association of America).
Pick the lower scale for a stronger coffee and the higher scale for a weaker taste.
Other coffee golden ratios for brews are:
- Pour Over 1:15 – 1:18 (ideal is 1:16.67)
- French Press 1:15
- (Inverted) Aeropress 1:15
- Cold Brew 1-8
- Siphon 1:15
- Espresso 1:2
COFFEE BLENDS:
A Coffee blend is combining beans from different countries or regions around the world to achieve a unique expression of flavor, acidity, and body.
As long as the mixture of beans are all from varying locations, it's considered a coffee blend.
SINGLE ORIGIN COFEE:
The term “single origin” is a coffee category focused on one distinct area or region where the coffee is grown. Coffee that is labeled as single origin can be traced to a single farm, a farmer, a producer, a crop, or a region in one country.
FLAVORED COFFEE
Flavored coffee can be created from natural herbs, spices, nuts, as well as from real food extracts. It can also be created from synthetic flavors.
There are three basic coffee flavoring techniques:
Real food flavoring: Infusing fresh coffee beans with real herbs, spices, and raw nuts.
Real food-flavored beans do not have a strong flavor-scented aroma.
Depending on the flavoring agent there may not be any flavored scent at all, the coffee may just smell like coffee.
Real food flavored beans do not display a powerful flavoring taste, the flavoring notes will be subtle riding on the coffee’s natural flavor notes rather than overpowering them.
Real food flavored beans may have a “strange” color due to the flavoring agent and may show the flavoring agent dispersed within the un-brewed coffee.
Real food extracts are flavor oils made from real herbs, spices, and nuts.
Real food extract-flavored beans have a powerful, clean, immediately recognizable aroma.
The flavored beans have a subtle to moderate flavor, the taste that is most pronounced when the coffee is drunk with milk or cream.
Real food extract flavored beans have a slight to rich oil sheen (depending on the roast) and should not be cracked.
Chemical coffee flavors, also known as synthetic flavor agents or oils, and are created in labs.
Chemically flavored beans have an overpowering, almost sugary-sweet aroma. They have a very sweet, artificial sugary taste to them that may be overpowering.
Chemically flavored beans tend to have a thick, shiny oil residue that will be visible on your hands, in the coffee bag, and in the coffee pot.
Neither natural nor synthetic flavoring, adds nutritional value to your coffee. That means no fat, calories, sugars, etc. are present in your coffee due to the flavoring agent
Most flavored coffees are designed to be drunk with milk and maybe a pinch of sugar. Some “flavor notes” may not be as pronounced if the coffee is drunk black.