Coffee Roasting Guide – Differences Between Light, Medium and Dark Roast

coffee roasting guide

Some foods need to be properly processed and prepared before they are ready for consumption. Seafood is the one that comes to mind when we talk about processing it before eating it. 

Similar is the case with coffee! 

Coffee beans don’t have those brownish tones right from their growth. They are green in color, and you might be shocked to hear that. So how they turn brown. Well, it is due to the process called coffee roasting. This process is both science and art, with the prior becoming more prevalent in the coffee industry.

It is a science because there are different variables that you have to deal with during coffee roasting. The type of coffee beans, how much they are exposed to air, what tools you use to roast your coffee, and several other quality issues.

In this guide, we will discuss all of that. So sit back and have a cup of coffee, because you will begin assessing your beverage in the end!

Why roasting?

Coffee roasting is key because this process brings out the taste in beans. Before this process, the coffee beans are green, and they move from the grower to the seller because they will not lose their quality and taste at this stage. These green coffee beans are squishy and soft, and they smell just like grass.

The taste and flavor come from the roasting process. Also, the beans become crispy and delicate. Their taste and color quality changes if they are exposed to elements. Therefore, the roasting process needs to take place near the consumer market to keep all the flavors and aromas intact. 

Once heat touches these beans, the clock begins to tick on their mouthfeel, taste, and overall brew quality.

A coffee bean is a seed that comes from the fruit of a coffee plant. Coffee producers get the fruit and remove the seeds from it after drying it. At this stage, it is called green coffee. It has different qualities and has numerous health benefits, but they don’t taste much like coffee.

If you have ever consumed sunflower seeds, green coffee tastes like that in some sort. These coffee bean seeds need heat to bring out all the flavors and aromas that are packed inside and to which we are more used to when drinking our coffee cups in the morning.

Coffee Roasting Process

The roasting process comes after processing and is followed by brewing. The process features sorting of the beans and then roasting them. 

Now the next step is to cool them down and get them ready for packaging. Large-scale coffee roasting houses also grind them.

 Different setups have different operations, but the basic steps are as follows:

  • The green beans are dumped into the hopper and are scanned to get rid of any debris.
  • The next step is to weigh the beans and then transfer them to the storage hoppers.
  • From there, these beans enter the coffee roaster, where these beans begin to absorb heat (347F) initially up to a point where they begin to give off heat.
  • Due to the endothermic (absorbing heat) and exothermic (releasing heat) phenomena, temperature adjustments of the roaster are required.
  • After that, the beans go into the draft inducer for cooling off.

During this roasting process, the beans can lose up to 15% to 18% of their weight. It is because of all the volatile compounds, and, of course, water content reduces in them. But their size increases dramatically because of the increase in cellulose structure, which helps in getting rid of the contents that we just mentioned. All these contents are released through steam.  

There are some conventional variations in the coffee roasting process used across the globe. For instance, in Vietnam, before roasting, coffee beans are coated with clarified butter and sugar. This process is called the butter roast. With this process, there is an additional caramelized coating on the coffee beans.  

Roasting time

The temperature at which you heat your coffee beans matters a lot for the flavor profile. But how long you roast it at a particular temperature is equally critical. 

When you roast your coffee quickly, you will get a flavor more focused on the aromas. But you don’t need your coffee beans to get burnt. 

A more consistent heat for a longer time will provide you a blend of different aromas and along with that burnt taste. With more temperature, you will get more burnet flavor and a strong coffee pinch. At low temperatures, the aromas will be on the fruit berry side.

Roasting stage

There are three primary roasting stages. These include the drying stage, the browning stage, and the development stage.

Drying stage

Coffee beans have moisture content in them that ranges between 8% and 12%. This moisture content doesn’t need to be there when the actual roasting begins. This stage lasts about 4 to 8 minutes in a proper drum roaster. At the end of this stage, the temperature needs to be 320F. Don’t heat the beans too much at this stage.

Browning stage

From 320F, the coffee beans begin to release aromas that match toasted bread. Here the aroma precursors are transforming into aroma compounds. Drying also continues during the browning stage. Browning occurs with Maillard Reaction that reduces sugars as well as amino acids to create different aromas along with color compounds called melanoids.

At this stage, the roasts slow down for the development of different flavors. At the end of this stage, the coffee beans begin to pop, which is known as the first crack, and from here, the next stage starts.

Development stage (roasting)

In this stage, the reaction transforms into an exothermic reaction, and the beans start to crack. During the previous two stages, the beans collected all the energy from the heat, and now they start to explode.

If you don’t slow down the heating process in this stage, you will get a coffee that has a very sharp, smoky flavor. The length of this stage accounts for 15% to 25% of the overall roasting time. It will be based on the roast degree and the flavor profile as well.

Roast Levels

There are typically three primary roast levels, and everything depends upon the color of the beans. These three primary levels include light roast, medium roast, and dark roast. There are various other levels as well, but the primary ones are discussed below.

Light Roast

Light roast coffees have a light brown color, and you will not find any oil on the surface of these beans. These coffees have crisp acidity, bright flavors, and mellow body. These beans are roasted to preserve the flavor traits of the beans. If the beans are properly grown, processed, and developed, they will produce a range of different tastes and aromas.

These coffees also have their unique aftertastes as well. These coffees can reach an internal temperature of 350F to 400F, and they don’t reach first crack, the time when the beans first began to pop. Other names of this light roast coffee are Half City, Light City, New England, and Cinnamon.

Medium Roast

Medium roast coffee has a typical brown color, and they also don’t have any oil on the surface like the light roast. These coffees come with medium acidity and body size. They also have a much more rounded overall flavor profile.

This level of roasting also contains many unique flavors of the origin of the coffee. But it also has an accent of deeply caramelized sweetness that comes from longer roasts. Consequently, these coffees are well balanced in their flavors and aromas but are also slightly sweeter and darker.

The brightest tones of a coffee will be lost here, but you will get that extra well-rounded flavor. These flavors and aromas are more approachable for regular coffee drinkers because they are less acidic and also have low intensity.

The natural flavor profile of the coffee remains intact. Medium roasts can reach 400F to 450F, and you need to roast them a little further than the first crack but not till the second crack. Other names of this roast are Regular Roast, American Roast, City Roast, and Breakfast Roast.

Dark Roast

There are not many dark roasts on the offer with ranging diversity because with dark roast, uniformity in the flavors and aromas increases. 

Dark roast coffee has been ruling the world for a long time primarily because the quality of the coffee bean, their aromas and flavors weren’t noteworthy back in the day. Less desired flavors were roasted away to get rid of the subpar coffee flavors to get more uniformity.

It was a good technique to get rid of the unnecessary characteristics of low-quality coffee. But this thing is not needed anymore because, in recent years, coffee beans quality has gone up significantly.

The goal is to focus on those deeper and darker yet pleasant flavors rather than getting rid of the bad flavors. These coffees can reach temperatures of 430F to 480F, which causes them to reach the second crack. Other names of dark roast coffees are Full City and Vienna Roast.

Other Coffee Roast Levels

There are various other roast levels as well. These include Spanish Roast, Italian Roast, French Roast, Espresso Roast, Continental Roast, and New Orleans. All these roasts are darker than the dark roast. These are the coffees that you can call “as black as night,” and they have a very oily surface.

These coffees don’t have any characteristics of their background and origin. And they just taste like ashy burnt coffee.  High-quality specialty roasters don’t roast their coffee this much dark because it is a waste of all the unique aromas and flavors.

Therefore, we also suggest you not to go for the beans that are roasted this much dark, unless you prefer to drink liquid charcoal. Specialty grade coffees have loads of flavors at different roast levels in them, especially if they have been roasted freshly.

FAQs for Coffee Roasting

What does coffee roast mean?

Roasting coffee means transforming the green coffee beans into brown ones with heat procedures. This process transforms the physical and chemical properties of those green-colored beans and roasted brown coffee and brings out unique flavors and aromas from within. 
At different temperatures, these coffee beans have different aromas and acidity levels that bring out different flavors. The tastes can even change if the heating process is elongated at different temperatures.   

What are the different types of coffee roasts?

There are different types of roasts, and they all vary in color and taste. But the primary ones are light, medium and dark. The light roast features more acidity in the taste and has a fruitier aroma.
Dark roast features a more burnt coffee flavor with less acidity but a strong taste. Medium roast is a blend of both light and dark roasts. It features a strong tasting coffee with hints of the unique characteristics of the origin of the coffee.
But there are various other types of roasts that include Turkish roast, Italian roast, French roast, High roast, Spanish roast, Vienna roast, Heavy roast, Espresso roast, Neapolitan roast, and  Double roast.

What type of coffee roast is best?

It is a highly subjective choice because different people have different tastes. Some people like more aroma and acidity in their cup of coffee, while others prefer more uniformity in the flavors. 
But only choose freshly roasted coffee beans because they taste amazing. The type of roast entirely depends upon your choice. There is plenty of room for everyone in the cafe.

Does dark roast have more caffeine than any other roast?

There is a common misconception that the dark roasts are stronger than light roasts. By volume, there is much more caffeine in light roasts if you compare them with dark roasts! 
But this difference is only applicable when you compare them both in terms of volume. The caffeine content is directly related to the bean size. If you make the comparisons by the cup, both light and dark coffees have the same caffeine content. A stronger tasting coffee doesn’t mean that it has more caffeine in it.

Coffee Roasting Guide Conclusion

Now you have realized how important the process of coffee roasting is. Coffee beans are green when they are picked, and they stay the same until they are processed. They need to be in this condition because they need to have all the flavors within them before the processing stages start.

Choosing the best type of roast is a highly subjective matter. Some people prefer to go for those acidic flavors in their cup of coffee. They should go for the coffees that are light roast. 

People who prefer a more burnt and uniform flavor should choose dark roasts. But don’t get too much carried away with the darker roasts because their flavor is very intense and ashy.

If you are looking for a stronger cup of coffee that will allow you to stay fresh and start your day, then choose light roast coffees. It is because they have more caffeine content in them by volume as compared to dark roasts.

So are you still on the dark side? Drop your comments and suggestions in the space provided below. Let’s keep the conversation going!