Not all coffee beans are given the special treatment of air-roasting, however we do air roast at Beanroasters and here are just a few reasons why…
Coffee beans are roasted to bring about the right balance between the acidity and sweetness of the beans. In other words, the process of roasting the coffee beans brings out their inner characteristics and flavour. The level to which a coffee is roasted pretty much decides how the coffee will taste upon brewing. For instance, coffee beans that undergo light roasting usually have a light bodied and sweet tasting brew; whereas, a full bodied coffee with a chocolatey flavour are dark roasted.
Air roasting coffee beans trigger certain physical and chemical changes in the beans. These changes include the loss of moisture, caramelising, change of colour and expansion of the coffee beans. As the beans start to lose moisture and expand, they make a popping sound, which is what we call “crack” in the coffee industry.
There are three basic levels of air roasting as far as coffee beans are concerned. The light roast as previously mentioned is used to derive a milder coffee, often sweeter tasting. Next comes the medium roast that is the most commonly used roasting level for coffee beans. Here, roasted coffee beans are done at the second crack. The next and final level of roasting coffee beans is known as dark roasting where beans are roasted till they appear oily on the surface; which happens well beyond the second crack. Roasting at this level tends to gives the brewer very full bodied and strong beverage.
Apart from the levels of roasting, there are three main methods of coffee bean roasting. One is an art, the second a science while the third is a combination of art and science.
Art roasting is a form of coffee roasting which has to be mastered through years and years of practice. Here the roast “master” can tell if a coffee has been roasted to perfection simply by using his senses of sound, sight and smell. On the other hand, science roasting is where the person brewing decides if a coffee is ready based on scientific data. They will tend to look for various data including time and temperature, in order to ensure that there is uniformity of colour amongst the different batches of coffee beans.
The third technique for roasting coffee beans is a combination of the previous two methods. It is generally used for mass producing coffee beans. Once the coffee beans are roasted, another process known as “cupping” is undertaken to ascertain the quality of the roasted beans. Here the coffee is tasted in a similar manner to tasting tea.
In this process, roasted coffee bean samples are extracted and measured in different cups. After that coffee beans from each cup are ground separately and then steeped in boiling water. Upon doing this the coffee grounds rise to the top and trap the aroma underneath. The “cupper” then removes the coffee grounds and smells the aroma. Lastly, the coffee is tasted and graded on various characteristics such as flavour, body, aroma, acidity and any defects in taste.
This step concludes the coffee bean air roasting process, after which it is up to you, the coffee consumer to decide which type of air roasted coffee beans suit your business best.