The Basic Science of Roasting
A lot of chemical reactions happen during coffee roasting, and they happen at different times, and different rates, depending on the specific outcome of the bean temperature for the roasting time. From this process, some different flavors occur and those differences are vital in the taste of the cup of coffee we drink.
Purpose of roasting
Roasting coffee completely transforms the chemical and the physical properties of coffee beans into a roasted product. The process of roasting coffee beans is what produces the flavor of coffee by having the green coffee beans to change in taste and aroma. Green coffee beans have increased levels of acid, proteins, sugars, and caffeine as those that have already been roasted, but they lack the roasted coffee taste due to other chemical reactions that occur during roasting process.
An industrial roaster makes an enormous amount of coffee to ship and sell to make a profit, while an “at home” coffee roaster will only make small batches for personal use.
Different Coffee Roasting Levels
There are 3 Primary Levels of Roasting Coffee: Light, Medium, and Dark.
Light Roasts: A light roast is light brown in color, with no oil on the surface of the beans a light body. Light roasts have a somewhat toasted-grainy taste and are more acidic. Light roasts also contain a higher level of caffeine than darker roasts.
Medium Roasts: Medium roasted coffee has a medium-brown color with more body than lightly roasted beans. Additionally, medium roasts don’t have the grainy taste like the light roasts do, this makes it have a more balanced flavor, aroma, and acidity.
Dark Roasts: Dark roasted coffees are dark brown in color, or sometimes it can even look almost black. The coffee will generally have a bitter and a smokier or even burnt taste. A lot of this decreases the amount of caffeine.
Different Cooling methods
- Pouring from one container to another: This is the simplest method of trying to cool your coffee for it to not burn your mouth. All you need is two containers. Try and keep some distance between the containers so that more air passes over the beans. Once more air passes over the beans, the quicker they cool.
- An electric fan: Blowing air over the beans while stirring them is another great way to cool them down. You will need to aim a small fan directly at the beans and keep them moving with a large spoon or whisk.
The roasting profession
A roaster will usually develop a blend that fits with himself/herself or can use one of another’s existing blends. The roaster can also have it re-branded in their own packaging that can then be sold to customers or even a wholesale. This allows them to earn an income while learning how to roast. This can provide you to eventually purchase your own roaster one day.