The Coffee Roasting Process

Coffee Roasting

When it comes to coffee, roasting is a big deal and rightly so. By transforming the physical and chemical properties of the green coffee, roasting releases the sealed aroma and taste inside it, bringing out the flavor we crave. Once the right temperature is achieved, green coffee transforms into brown beans we see in commercial stores – the coffee we are familiar with. The once soft beans become hard and crunchy and with a bit more magic, become the elixir we all love.

How is roasting done?

After hulling, bags of green coffee beans are transported to roasting houses. But before they go through the actual roasting process, they are first screened to remove debris with the help of a hopper. Once sorted, the beans are then weighed and transferred to storage hoppers by a belt. From here, they are sent to the roaster and the roasting process finally begins.

The beginning of the roasting process is endothermic, meaning the beans are absorbing the heat. Roasters need to be mindful and sensitive to the changes taking place in the beans as they might need to adjust the temperature. When the heat reaches around 175 degrees Celsius, the beans begin to release the heat and the process becomes exothermic. Once the beans have been processed according to their roast level, they are transferred to an enclosure to be cooled quickly.

Several physical changes can be observed during the roasting process. But perhaps the most significant is the change is size –they become wider but lighter in weight due to the dehydration that takes place during the process. See, roasting releases water and other compounds, but the release of these chemicals result to the expansion of the cellulose making the beans wider.

It is important for a roaster to sense when the beans reach their required roast level. A matter of seconds will cause a big change to the taste and aroma of the beans. Hence, roasters need to have skills and expertise to come up with quality coffee.

Roast Level

The roast levels of coffee beans depend on the length they are roasted. There are four roast categories: light, medium, medium-dark, and dark. Coffee lovers have different preferences when it comes to roast level, and this is often because of geographical and cultural influences.

Light roast beans are brown and referred to as mildly-roasted. They tend to be dry to touch because the short roasting time does not permit the oil locked inside the beans to reach the surface. Some terms used to refer to light roast are Light City, Half City, and Cinnamon.

The medium roast will also result in brown non-oily beans, but the taste is stronger than the light roast. This type of beans is preferred in the United States; hence, it is often known as the American roast. Other names medium roast is referred to are City and Breakfast.

Medium dark roast beans have rich dark color and are slightly oily. They have a slight bittersweet taste. These beans are also called Full City by some roasters.

Dark roast beans are shiny, black, and oily. It has a definite bitter taste, but they are less acidic. The darker the beans are, the lesser their acidity level is. There are many names used to identify dark roast beans such as High, Continental, New Orleans, French, etc. Hence, to be sure, it is better to ask before you purchase.

Roasting with Phantom Series

After knowing how coffee beans are processed, it is good to choose your roaster to ensure a quality and desired level of roast will be achieved. Phantom Series coffee roasters offer an advanced system for controlling and monitoring the roasting process. With its PC-integrated technology, you can be sure to have Specialty Coffee easily. Along with the advanced technology comes its safety features too. You can be sure to minimise personal injuries and machine damages. When it comes to quality, Phantom Series uses high-caliber materials for a long-lasting efficiency. Contact us at +61-7-5529-0888 or send email to for more enquiries.

Coffee – From The Plant To Your Cup!

Coffee Berries

With every sip, a coffee lover falls deeper and deeper in love with his cup of coffee which hard as it is to sometimes believe, began as a seed, then a plant, and finally a bean. With the delicate processes these beans have to go through, it’s no wonder that they do not just taste good but also beneficial to our well-being. Let’s discover how a seed becomes a source not just of energy but also happiness to many.

Plant and Harvest

Coffee seeds need to receive appropriate care for them to grow into a quality bean. For starters, seedlings need to have plenty of water, but not too much sunlight. Hence, watering them needs to be done often and mindfully at that. Farmers also use shade to protect the plants from direct sunlight. Once matured, they are transferred to a moist soil to be permanently planted.

The fertility of newly planted trees depends on its variety, but they may bear fruits in about 4 years. Coffee cherries which are the fruits of a coffee tree, can be harvested when their color becomes a bright deep red. Harvest happens once a year, but there are countries that harvest twice. There are two ways of harvesting coffee cherries: strip or selective picking.

From the word itself, strip picking is the stripping of all cherries off a branch either by hand or with the use of a machine. On the other hand, selective picking is done manually because the pickers are selective and will pick only the fruits at the peak of their ripeness.

After collecting all the harvest, the coffee cherries are then transported to be processed.


Coffee harvests should be processed as quickly as possible to maintain their freshness, and there are two ways to process them: the dry method and the wet method.

The Dry Method is laying down the coffee cherries directly under the sun. The cherries will be turned over several times during the day and be covered at night or during rainy days to avoid spoilage. Drying will continue for many weeks until the moisture content drops to 11%.

The Wet Method is done with the help of a pulping machine which will remove the skin and pulp of the bean. The beans are then separated according to their sizes and weight. Lighter beans will float to the top of the water channels, while the heavier ripe beans will sink to the bottom. Once the best beans have been extracted from the batch of harvest, they will be stored in large fermentation tanks filled with water for 12 to 48 hours. Enzymes that naturally occur during fermentation will dissolve the remaining layer of the beans. After fermentation, the beans will feel rough, be rinsed, and dried either by the sun or by a machine.

Dried beans are referred to as parchment coffee and are milled in three steps –from hulling, to polishing, and to grading and sorting. Hulling is the removal of the entire dried husk of the coffee bean. Polishing is another step, although optional, to remove any silver skin left on the bean after hulling. Lastly, grading and sorting are done to carefully choose the beans without any color flaws or imperfections and separate them according to size and weight.

The milled beans, now referred to as green coffee, are stored in sacks to be transported.


Green beans are chemically and physically transformed into brown coffee beans. The beans move in a continuous one direction until the desired roast level is achieved. The flavor and distinct smell that the coffee beans produce is because of pyrolysis. Pyrolysis allows the bean’s fragrant oil, known as caffeol, to rise to the surface once the temperature reaches 400 degrees Fahrenheit. This temperature also turns the green color of the beans to brown.

Software such as the Coffee Sweet Prosweet is also utilised during the roasting process to closely monitor the roast level and many of the other subtle factors that apply to roasting coffee.

Roasting with Phantom Series

There are many state-of-the-art coffee roasters developed along with advances in technology. When it comes to superior roasting, the Phantom Series is in the lead having the most advanced PC integrated system. With its 3 phase motors and gearboxes from Italy and Omron and Schneider Electrical components, you can be sure that it is of high quality and would last for many years.

When it comes to performance, heat transfer for optimum roasting can be achieved because of its double wall carbon steel wall design with gaps that are 3mm apart. No need to allot time for cooling as roasting and cooling are done simultaneously, helping roasters keep up with the demand. The roasting process can also be monitored through the viewing glass.

Adapting to automated era, Phantom Series offers automatic loading of coffee into the drum with its automatic hopper door with electric actuator. Surprisingly, the operation is quiet because a compressor is not required. Operation settings can also be saved for future roastings thanks to its memory function. And in case of system issues, PC connection can be done as a backup plan.

Safety is also equally important in designing the Phantom Series. Temperature monitoring is done through 5 independent thermocouples. A cyclone water sprinkler is also available when things go wrong. All automated doors are covered and protected by the hinged cooling tray to avoid accidents while the process is running. Maintenance and repair might trouble you because of the Phantom Series’ advanced issues, but nothing to worry as all main serviceable areas and components are available.

To enquire about the Phantom Series Roasters, please call +61 7 5529 0888 or send a message through the online Enquire Now form.

Grinding and Brewing
Once coffee beans are perfectly roasted, they are ready for grinding. The grinding process gets the most of the flavor from the beans; while brewing controls the coarseness of the coffee grounds.

The process of converting a seed to a brewed drink that you pour into your cup may look like a tedious process, but with the pleasant aroma and flavor that quality coffee beans offer, all the hard work is worth it.