Hayman - Finest World Coffee

How Do Coffee Roasters Work?

coffee roaster


Chances are that if you know a thing or two about coffee, you’ll know there’s a roasting process involved. And there’s also a good chance you’ll know that the coffee roaster plays an important role in producing outstanding coffee. But at the same time, you might not know why. Likewise, you may be curious as to whether investing in a coffee roaster for personal use is something you should be doing.

As for the basics, coffee roasting refers to any process whereby the green coffee beans are treated, in order to produce the final roasted beans. Incredibly, in a single roasted coffee bean there are more than 800 aromatic molecules. Decades ago, coffee roasting was something the majority of households took care of themselves. These days however, it is typically left to the coffee producers to take care of the roasting process, before the final beans are packaged and shipped.

Why do we roast coffee?

Covering the most obvious question first of all, roasting is by a wide margin the single most important step in the coffee production process. Freshly picked and initially processed green coffee beans are almost entirely flavourless. With the application of heat however, the green coffee beans undergo a variety of radical changes, which include:

  • The beans inflate 50 to 100% and lose some of their water
  • They lose their green colour and take on the more familiar brown
  • A variety of chemical compounds break down and produce the flavour of the coffee

While the roasting process is essential for creating the deep and rich coffee flavour we all love, the full flavour profile will be determined by a variety of factors. These include the geographical origin of the coffee, altitude of the farm, soil types, humidity, climate, processing conditions after the initial harvest, final preparation of the beans and so on. However, roasting is an essential part of the process and plays the most pivotal role in creating the flavour you’re familiar with

Chemical Reactions

So with the basics taken care of, it’s now onto a little rudimentary science.  When heat is applied to green coffee beans, caramelisation of the sugars and natural assets within the bean produce the familiar coffee colour and flavour. In addition, the chemical change that happens after this reaction leads to the production of carbon dioxide. Which is precisely why quality espresso made using the finest beans presents an amount of foam or ‘crema’ on top. This is the carbon dioxide released during the roasting process.

DIY Roasting

Right now, it’s perfectly possible to pick up a decent coffee roaster to use at home, giving everyone the opportunity to take over the roasting process themselves. What’s more, coffee roaster prices have been declining significantly over recent years.

Nevertheless, this doesn’t necessarily mean that home roasting is the best approach for everyone. The reason being that it can be a somewhat precise and intricate process – one that needs to be approached with care and attention, in order to avoid burning or destroying your beans.

From temperatures to timings to ensuring every bean is exposed to just the right amount of heat for the right amount of time, you need to know what you’re doing to get the best out of a coffee roaster. What’s more, it can be trickier than you may expect to get hold of the green coffee beans in the first place, in order to then go about roasting them yourself.

On one hand, if you fancy giving it a go and don’t mind investing the necessary effort, trying your luck with a coffee roaster can be a lot of fun. And of course, the aromas produced by the average coffee roaster are no less than intoxicating.  However, you may find it easier, cheaper and more reliable to simply buy beans that are roasted as close as possible to the time you purchase them. Just as long as the beans have been roasted recently, they will still be in their prime and produce outstanding coffee.

As such, it all depends on where you buy your beans from and the quality of the coffee you demand. If your standards are high enough in these areas, you might not need your own coffee roaster after all!

For the best specialty coffee, freshly roasted for you on shipment day, click here and visit Hayman's coffee store. 

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