Last Updated on
A great cup of coffee starts with the beans. Poor quality beans will produce poor quality coffee that no true coffee lover will enjoy. It’s not only the beans themselves that matter, but the way and extent to which they’re roasted. And how you prefer to drink your coffee, whether it’s an espresso, latte, or even frappe, will affect what bean is right for you.
With all the different coffee types available on the market, finding your ideal coffee partner might seem impossible. However, understanding the different qualities of both the beans and the roasting processes will help you find the perfect blend for you and your preferred coffee drink.
Coffee beans can vary considerably in their size, shape, colour and taste. It all depends on the type of bean, where it was grown, and the natural conditions they were grown in, which includes soil type, altitude, and rainfall.
Because of this, even the same variety of beans can vary considerably from region to region. However, while it can seem like there’s an overwhelming range of beans available in reality there are two main bean types, which form the vast majority of available blends.
Arabica accounts for over 60% of all beans produced globally. This bean thrives at high altitudes in shady areas that receive a consistent amount of rainfall through the year.
Sometimes referred to as gourmet coffee, Arabica beans demonstrate a complex, delicate flavour with low acidity, and have an aromatic nose.
Many of the Arabica coffees are named after the region they originate from, such as Kenya and Blue Mountain. With their delicate taste, Arabica is best served without milk, cream or sugar, and it’s unsuited to iced coffee.
The second most widely produced coffee bean, Robusta is considered a slightly inferior coffee to Arabica. Unlike Arabica, it can be grown at any altitude but prefers a hot climate with irregular rainfall.
With almost twice the caffeine of Arabica beans, for those looking for a real caffeine hit combined with a deep, rich taste, Robusta the perfect choice.
It’s strong enough to work well with milk and sugar, making it ideal for latte and cappuccino, and iced coffees.
Now you understand the differing tastes of coffee beans, it’s time to look at the different roasts you’re likely to come across. The roast type and method used has a massive impact on the final appearance, flavour and taste of your coffee.
After all, it’s what turns the bean from the soft, green, largely tasteless product that it starts as, into the aromatic, crunchy and flavoursome bean that we brew.
There are four main types of roasting:
light, medium, medium-dark, and dark, which refer to the colour of the beans once they’ve been roasted. The change in colouring is caused by oils in the beans rising to the surface as they’re heated and is determined by the internal temperature they reach, and the length of time they’re roasted for.
Light roasts are heated to between 180-205℃, creating a taste of toasted grain and higher acidity. They also tend to be the beans highest in caffeine, as caffeine decreases with higher temperatures.
High-quality beans or varieties with very distinct flavours are usually light roasted as this method allows the flavour of the coffee to shine through. A lightly roasted bean generally looks dry, as the oils haven’t permeated the outer skin.
Medium brown in colour, medium roasts are heated to a temperature of around 210-220℃.
They demonstrate a greater depth of flavour than light roasted coffee, with a more balanced combination of flavour, aroma and acidity and a slightly sweet, toasted flavour.
Like light roasts, the oil doesn’t penetrate the surface of the bean, maintaining the beans’ dry appearance. Balanced, easy drinking, and adaptable, this is the most popular roast in the commercial market.
The oils start to show on the surface of medium-dark roasted beans, which are a darker colour than the previous two roasts. Heated to around 225-230℃, the taste of the roasting process becomes noticeable, and the coffee taste may have hints of spice.
Any acidity disappears completely and, again, beans roasted this way will contain less caffeine than the two roasts already covered.
Dark roasted coffee is roasted until the oil rises to the surface and the sugars of the bean start to caramelise, reaching a temperature of 240℃.
They can appear almost black in colour, and may have an oily appearance thanks to the oils. The predominant taste is of the roasting process, which is strong, smoky, and sometimes spicy, and so this roast is usually reserved for lower quality beans.
These beans are most widely used for espressos.