The raw – un-roasted coffee bean is yellowish green in colour, dry and hard.
As the bean gets roasted, the colour starts changing to light orange and then to a light brown colour as it approached the 1st crack.
At around this stage, a great deal of the coffee bean’s moisture is extracted and the coffee bean can be considered light roasted.
As the roasting process carries on, the coffee bean gets puffed up and darker in colour. As we are approaching the 2nd crack of the coffee bean, we have entered the medium roast stage. The coffee bean is dark brown in colour & quite dry.
Anything after this stage is considered dark roast. The coffee bean appears to be fully puffed, very dark brown (bordering black in some instances) and oily.
As the roasting progresses (from light to dark), the basic elements of the coffee bean – being acidity, aroma, flavour & body – changes.
The darker you roast the more compromised they become BUT having said that, it is also important to note that each coffee bean type has different limits & reacts differently to roasting.
In general lines and as far as roasting is concerned, one can accept that the darker the roast gets the bigger in size and lighter in weight the coffee bean becomes. This means that a scoop of light roasted beans will offer more caffeine than the same scoop filled with dark roasted beans BUT if you were to do the same exercise using weight instead of volume, the dark roasted beans will offer more caffeine in the cup.
Lastly, one needs to also take in consideration the type of coffee bean being roasted BECAUSE different types of coffee bean not only behave differently when roasted but also offer different caffeine content, for example Robusta type coffee beans offer nearly double the amount of caffeine than Arabica coffee beans.
So, one could assume that there are different coffee roasts for different folks! Reality prompts us though to consider naming “most popular roast” the one that clearly appears to be selling faster. As far as South Africa is concerned, the roast that gets the title is the medium roast!
Arabica & Robusta coffee beans are the two main species of coffee. Arabica coffees hold the 70% of the global market’s consumption while Robusta the remaining 30%. Arabica type coffees appear to hold more sugar & oils that lead to their taste characteristics being Sweet, Fruity and Zesty Acidity while Robusta coffees reveal Woody & Earthy notes with lower acidity levels.
Arabica coffees are commonly found to be used in single origins blend while Robusta coffees are often used as “fillers” to coffee blends and the coffee of choice for many instant coffee manufacturers. Arabica coffees cost more than Robusta coffees and this is because Arabica coffee trees can be found mostly in high altitude areas, they are more susceptible to pests, require more attention by the farmer and produce lower yield.
Robusta coffee trees on the other hand, grow in lower altitude, they are more resistant to pests requiring less attention from the farmer and yield higher production.
Another big difference between these two types of coffee is the caffeine concentration: Arabica runs at about 1.5% concentration while Robusta runs at about 2.7% concentration.
As far as appearance is concerned, Arabica coffee beans are more oval & flat while Robusta coffee beans are more round in shape.
By the end of the day, one needs to take in consideration that the amount of Arabica coffee bean fans appears to be as big as the amount of Robusta coffee bean fans. Such realisation could easily prompt us to consider the process of choosing between these two – different in many ways – coffee bean families a simple matter of taste!