A cuppa joe is usually the way most people like to start their day off; A Nescafe tarik here, a fancy latte complete with foam art there, or just a simple shot of espresso. Coffee is available everywhere in many different forms but how much do you actually know about it? Here is a little guide that will give people the impression that you are a coffee expert.

Coffee beans are grown in semi-tropical countries, at altitudes ranging from sea level to about 6000feet. The best grades are grown at considerable elevation whilst the lower altitude coffees are more likely to be of little cup value.

Get to know the species:

The Arabica tree produces 70% of the world’s coffee and is the oldest known species of coffee tree grown only in mountainous or volcanic areas. The optimum climate for this tree is an area with a yearly average temperature of around 15-24°C, with about 150-200cm of annual rainfall. The Arabica trees take up to nine months for the fruit to mature and may usually only produce a mere 5kg of fruit in a year. These beans are generally larger, longer, and flatter compared to other varieties and they also have less caffeine. The Arabica coffees are the most expensive due to the difficulties in growing and they have a more delicate, acidic flavour.

Robusta trees are grown in tropical areas in altitudes from sea-level up to 2,269ft. They can stand much harsher conditions and rainfall while still producing a higher yield than the Arabica. These beans are more hump-backed and the flavour is not as desirable therefore used mostly in blends. They are however caffeine rich and despite being cheaper in price they only account for 30% of the worlds coffee production.

The Margogype is the most famous mutant from an Arabica variety. These trees produce the largest beans and are usually sought after for the smooth flavour and attractive appearance.

"Get to know your coffee"

What is all this talk about roasts?

Coffee roasting is simply the process of applying heat at a temperature just above 200°C to the raw beans so that it is able to be consumed and digested by humans. Without this process the bean has a grassy flavour. While roasting the coffee bean undergoes a multitude of chemical reactions and this is where it develops its characteristic flavour and aroma profiles.

As easy as it may sound, the process of roasting coffee is very complex and hard to execute accurately. It has to be controlled and the beans are roasted and removed at precise moments. The beans have to achieve a constant colour throught from the outside right through to the middle.

Roasting time has an effect on the flavour components of the coffee and these can be tweaked slightly depending on the outcome:

- Acidity develops at the beginning and with time, it diminishes as the coffee becomes darker.
- The Body of the brew increases with time as the coffee is roasted darker.
- The Aroma and Flavour reach a peak during the roasting process and with time diminish as the bean is roasted darker.

A good example of this is the Costa Rica which has an almondy characteristic when the coffee is lightly roasted. As it becomes darker, this characteristic diminishes until it becomes undetectable and lost within the burnt flavour of the caramelised bean.

Filtered coffee can be lightly roasted as it is more diluted than an espresso coffee, and the acidity of the bean (if it is prominent) can be maintained. On the other hand an espresso coffee is more concentrated and needs a darker roast to reduce the acidity as well as to swell the beans further so that there is better water penetration through the bean. With that being said, darker roasts may also be used for filtered coffee but lighter roasts are not suitable for coffee aimed at making espresso.

What do I need to know about grinds?



Grinding the coffee beans to a particular size influences the final brew. The grind size of the coffee reflects the brewing method in addition to its role in affecting the overall flavour profile. If the coffee is ground too fine, it may hinder the passage of water filtering through whilst a grind that is too coarse will result in water passing through too quickly resulting in a weak coffee. Therefore an optimum grind is needed to be achieved in order to bring out the potential of the coffee and keep its balance.

The general understanding is that finer grinds tend to be more acidic, have more flavour and aroma within the final cup. This is due to the fact that the surface area of the ground particles is larger resulting in a more complete extraction. The spaces (interstices) between the grounds are smaller which makes it more difficult for water to pass through the coffee. This prolongs the water-particle contact and therefore a greater extraction of coffee. However in terms of brewing in an espresso/pressure machine, if the coffee is too finely ground, brewing time will be extended resulting in bitterness.

Grind Guide

Drip coffee makers (flat bottomed filters): Medium – Gritty like coarse sand
Drip coffee makers (cone filters): Fine – Smoother to the touch a little finer than table salt
Plunger pot / French press: Coarse – Very distinct particles of coffee like kosher salt
Percolator: Coarse - Very distinct particles of coffee like kosher salt
Espresso machines (pump or steam): Extra fine - Finer than sugar, but not quite powdered
Espresso moka pots: Fine - Smoother to the touch a little finer than table salt
Vaccum coffee pot: Coarse – Very distinct particles of coffee like kosher salt
Ibrik: Turkish – Powdered, like flour


With contributions from Coffex Coffee.

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