Roasting of Coffee
It is through the process of roasting that green coffee beans are transformed into various flavors of coffee and other products. Variations in modes and techniques of roasting manifest in various flavors and varieties of coffee products.
While there are slight changes in the level of essential ingredients like caffeine, acid, sugar, and proteins, the taste varies to a larger extent in different flavors and products. The process of rousting induces physical and chemical changes in the raw material, which is green coffee beans, and transforms them into the desired final products.
The critical chemical reaction that changes the raw coffee beans into the roasted, finished products is called the Maillard reaction. Fostering a chemical reaction between the chemical ingredients of coffee gives the distinctive flavors of the end products. It is not limited to coffee only. And instead, it encompasses the processing of a wide variety of foods, including steaks, biscuits, and bread pieces.
The bulk of the coffee in the market mainly roasts on a large scale through big machines, but small-scale roasting has also come into vogue commercially with the unique flavors served at specialty shops. There are further varieties in the process of roasting in the non-commercial, personal domain.
Heat applied is the generally applied criterion of the light, medium, and dark roast coffee. During absorption of heat, the color of the coffee darkens to yellow and different shades of brown. The coffee color also darkens over time; hence color may not be considered the only indicator of the degree of roasting.
In modern times, a combination of multiple factors, including temperature, smell, color, and sound, is employed by the roasters to check and regulate the roasting process. During heating, the coffee beans emit different kinds of sound during the process, taken as a reliable sign of the level of heating. For example, at approximately 385 F, it will give out a cracking sound, and at 435 F, a second crack.
The way of roasting coffee is one of the main factors that influence the taste of that coffee. The process of roasting changes green beans into flavorful and aromatic coffee that refreshes in the morning. Thus, bean roasting changes the physical form and taste of the coffee. Several large manufacturers of coffee roast it in enclosed drums that can, at times, burn the beans they have.
The use of perforated drums can help protect the aroma and smooth flavor of each level of roast at a suitable temperature. The light roasts’ duration lasts until the time there is a single crack in them called their first crack. With the increase in the magnitude of roasting, the beans get heavier and thicker until they crack for the second time. It is impossible to roast coffee after the second crack as the beans tend to get thinner and taste like that of charcoal.
The coffee is more in its pristine character at lighter roasts. As more heat is applied, the innate flavors of the coffee are shadowed by the flavor’s consequence of the process of roasting. The darker hues it takes, the more it takes on the roast flavor, and the more difficult it is to discern the original flavor of the beans. The caffeine ratio is also inversely proportional to the roast level as it diminishes with the increasing roast level, unlike sugar level and density which increase during the process.
At higher temperatures, greater than 450 degrees Fahrenheit, the beans get burned, and their taste gets like that of charcoal.
Light Coffee Roasting
Form 385ºF to 401ºF is taken as a Light Roast, which is almost promptly after the first crack. After some minutes of heating, the beans start to expand in size and crack. Very light roast is characterized by underdeveloped sweetness, with pre-dominantly roasted grain, close to the original flavor, and sharp acidity. It has a less obvious roast flavor and is preferred by those who go for the original taste of the coffee. It boasts high acidity with original taste. It is popularly known as American Roast, New England Roast, and Cinnamon Roast.
Medium Coffee Roasting
From 410ºF to 426ºF is termed as a Medium Roast. It is medium-light brown to medium brown in appearance with a slightly subdued acidity, improved sweetness but still dominant original taste. It is also developed through the first crack. It also embodies the signs and aroma of roasting. Generally called City/Full City Roast.
Dark Coffee Roasting
From 437ºF to 473ºF is taken to be Dark Roast with the variations of Medium Dark and Moderate Dark. It is in a variety of shades of dark brown with patches of light surface oil. Heightened sweetness and diminished acidity also include the salient features.
The bittersweet flavors and pungent/dominant aromas of roast prevail. Generally referred to as French Roast, Vienna Roast, Italian Roast. And Full City Roast. The coffee manufacturers hide the dark beans of coffee with dark roasting. Still, other manufacturers focus on enhancing the aromas, intense, and bold flavors that are a characteristic of a dark roast.
Light Roast Coffee
The color of light roast coffee is light brown and there is no color on the bean surface. In this type of coffee, you will find brighter flavors, crisp acidity, and a mellow body. The roasted versions of these coffees keep the beans’ original features, which are unique to them.
The beans of light roast coffee often reach an internal temperature ranging from 350 to 400 degrees on the Fahrenheit scale. Those beans barely get to the cracking stage, where the vapors inside them come out from the bean’s outer walls, which gives off the noise of cracking. The Light roast coffee is also called New England Roast, Cinnamon Roast, and Light City Roast.
The flavor of the light roast coffee is referred to as ‘bright’ by their enthusiasts. This takes place because their beans get denser due to the moisture that stays inside them. The flavor of this coffee is herbal or fruity.
Medium Roast Coffee
The color of the medium roast coffee is brown, and the surface of it is oily. The acidity of these coffees is medium. As these coffees are also not heated to higher temperatures, several features of the original coffee are preserved. They come in several different flavors, as the original characteristics of them are preserved during the process. Also, these coffees are sweater, darker, well-rounded, and balanced.
The medium roasts are less intense and acidic as they contain several features from the original green bean of coffee. The medium roast coffee is also called the city roast, American roast, and city roast. It comes with many flavor notes, such as molasses, cacao, and raspberry. The flavor, acidity, and aroma of medium roast coffee are more balanced than the dark and light roasts.
Dark Roast Coffee
The color of the dark roast coffee is dark brown, and it frequently has an oily surface. These types of coffees have a heavy body, lesser acidity and their flavor is darker and deeper. The coffees roasted to this magnitude do not have any of their original features left in them. Nevertheless, it does not imply that they are boring and bland. The coffees with nutty, chocolate and caramel flavors come in the category of dark roast.
Alternatively, the dark roasts are also called Vienna roast and full city. The dark roast coffee bean loses more moisture, thus becoming less dense, with a smoky or bitter flavor. With darker roasting of beans, the original flavors and content of coffee burn out. The acidity level and the extent of caffeine in darker roasts are lesser than that of other roasts. The strong and smoky flavor of dark roasts comes from the oil on the surface of their bean. The medium and darker roasts of coffee do not have any oil on their surface.
Increase in the Variety of Coffee Beans
The trend of consuming dark roast coffee had been more during the past few years. The dark roast coffee had a strong taste, and it symbolizes a hardened, seasoned palette. The taste of light roast coffee was considered weak.
Now, light roast coffee is a popular choice. The reason for strong variation in the tastes of light and dark coffees is the increase in the diversity and variety of coffee beans used in them, because of which the beans of coffee with the best tastes are a lot easier to find.
Now, the light roast coffee has more complex flavors. This also means that coffee is getting better day by day. Dark roast coffee has more caffeine and a stronger flavor. It sometimes has a tinge of the flavor of toasted pine of chocolate.
Taste of Light Roast Coffee
The citrus in the light roast beans of coffee can be pleasing for your taste buds. Consider a report by the National Coffee Association in the USA, which mentions that Medium roast coffee is a preference for several drinkers of coffee in the USA. The reason is that the medium coffee is a bit sweeter than the light coffee, and it offers a balanced acidity and flavor.
Level of Caffeine
The level of caffeine is greater in light roast coffee. Their beans are denser than those of dark roast coffee. The density of dark roast beans of coffee is slightly less. Thus there is less caffeine in each of those dark roast beans.
Quality and Taste of Coffee
The quality of coffees has notably improved from that in the past. And for that reason, the dark roast is not the most preferred flavor for coffee. To avoid low-quality coffee, the coffee manufacturers roasted away the less pleasing flavors of coffee to find more approachable, uniform, and desirable tastes.
Presently, the aim of roasting is not to crush the bad flavors but to get darker, pleasant, and deeper flavors if this is required in any of the coffees.
Even more concerning is that many coffee brands contain a lot of pesticides, toxins, and mold in their beans, which affects their quality. So, it is important to be careful about the quality of coffee while buying it to avoid any harm to health. The mycotoxins and molds can stay in the intestine lining, which triggers oxidative stress and inflammation. Moreover, long-term exposure to them can cause chronic fatigue, cancer, and even respiratory problems.
Caffeine in Coffee
With the increase in the level of roasting of the beans, their caffeine content continues to decrease. This means that at a lower temperature, the light roast coffee preserves more of the caffeine from the initial green bean of coffee.
The medium roast coffee has a slightly thicker bean than the light roast coffee. However, it loses some of its taste in the process of roasting. So, it lacks in the bright floral flavors, which are a characteristic of light roast coffee. The amount of caffeine in these coffees is medium. To get this type of coffee, the bean is roasted till the second crack. Dark roast coffee comes in several names, which can be confusing for the consumers.
As dark coffee beans are roasted more so, they lose much of their original taste, and they tend to gain flavor from the process of roasting.
Health Benefits of Coffee
The light roast coffee also has a higher content of antioxidants. Though, the medium roasted coffee still has the highest number of antioxidants in it that are useful for health. Dark roast coffee increases the level of an antioxidant called glutathione.
The medium and light roasts contain a high amount of a potent antioxidant called polyphenol chlorogenic acid (CGA), which is beneficial for health. CGA repairs the damaged cells, decreases inflammation and lowers the cholesterol level that improves complexion. It also makes a person more active by increasing the levels of immunity and energy.
The amount of CGAs is far less in the darker roasts. Glutathione is also called a master antioxidant; thus, it can increase the level of vitamin E that heals the skin. This antioxidant serves the function of restoring the red blood cells (RBCs).
Now the coffees come in a greater variety of flavors, so you can choose any of those coffees that benefit your health and appeal to your taste too. If you want a high level of caffeine in your coffee, you should take light roast coffee.