Roasting Speciality Coffee vs. Commercial Coffee: How Different Flavours Are Brought Out

Roasting is an art form in the coffee world, where the skill and precision of the roaster can dramatically alter the flavour profile of each bean. Yet, the approach to roasting varies significantly between speciality coffee and commercial coffee.

Commercial Coffee Roasting: Consistency and Mass Production

Commercial coffee roasting is largely driven by the need for speed, uniformity, and consistency. Commercial roasters often work with large batches of beans from multiple origins to produce blends that taste the same year-round. This allows major brands to provide a familiar, consistent flavour to consumers but comes at the cost of flavour depth and nuance.

To achieve this, commercial coffee is generally roasted to a darker level. Darker roasts not only produce a strong, bold taste that is popular in mainstream coffee but also mask the subtle flavour variations in the beans. Dark roasts also help ensure that beans from various origins can be blended together with little noticeable difference, creating a more standardised flavour. For example, popular commercial coffees often have chocolatey or smoky notes, achieved by roasting the beans at higher temperatures for longer periods.

This approach reduces the risk of bitterness from lower-quality beans, as the darker roast can cover up less desirable flavours. Additionally, dark roasting extends the shelf life of coffee, which is advantageous for commercial coffee that may sit on shelves or in warehouses for months before it reaches the consumer.

Speciality Coffee Roasting: Emphasis on Artistry and Flavour Nuance

Speciality coffee, however, takes an entirely different approach. In the speciality coffee industry, each coffee bean is treated with a focus on its origin, variety, and inherent flavour profile. Speciality coffee roasters work closely with farmers to source beans from specific regions, often selecting single-origin beans that reflect the unique qualities of their terroir. The emphasis here is on quality over quantity, and speciality roasters often buy beans with distinctive flavour characteristics in mind.

Roasting speciality coffee is a delicate process, typically done in smaller batches to allow the roaster greater control over temperature and time. The aim is to highlight the natural flavours of the beans, which can include a variety of notes—from fruity and floral to nutty and chocolatey. Light and medium roasts are more common in speciality coffee, as these levels of roasting preserve the unique flavours and acidity of the beans rather than masking them.

For instance, a lightly roasted Ethiopian coffee might exhibit bright, fruity notes like blueberry or citrus, while a medium-roasted Colombian coffee could have a balanced profile with hints of caramel and chocolate. This level of specificity requires roasters to understand not only the science of coffee roasting but also the delicate balance between temperature, airflow, and roasting time to bring out these nuanced flavours.

How Speciality Coffee Roasters Develop Different Flavours

The roasting process itself is both a science and an art, and in speciality coffee, roasters experiment with multiple techniques to enhance the unique flavour potential of each bean. Here are some methods used to achieve this:

1. Temperature Control and Profiles: Unlike commercial roasting, which often relies on high temperatures, speciality coffee roasting uses carefully monitored temperature profiles. By adjusting the temperature at specific intervals, speciality roasters can control the development of acidity, sweetness, and body. For instance, starting with a lower temperature can highlight the fruitiness in beans, while gradually increasing heat can deepen caramel and chocolate notes.

2. Roasting Curves: Speciality coffee roasters often use “roasting curves” to track and adjust the roast in real-time. This involves plotting temperature changes over time to ensure consistent development of flavours. Through “ramp-up” (increasing temperature) and “development time” (holding the beans at a certain temperature), roasters can extract the maximum potential of each coffee’s flavour.

3. Airflow Management: Speciality roasters adjust airflow to control how the beans respond to heat. Higher airflow can enhance acidity and brightness in the coffee, while lower airflow creates a denser, richer body. The choice of airflow depends on the bean type and desired outcome, making it an essential variable for bringing out specific flavour characteristics.

4. Batch Size and Precision: Roasting in small batches is a hallmark of speciality coffee, allowing for precise control over the roast profile. Small batch roasting enables roasters to make quick adjustments as needed, whether to enhance sweetness, reduce bitterness, or highlight floral or fruity notes.

5. The Importance of Cupping: After roasting, speciality coffee is often “cupped,” or tasted, by the roaster to evaluate the flavour profile. Cupping is a crucial step in determining the quality of the roast and identifying any adjustments that may be needed in the next batch. Through cupping, roasters learn to refine their techniques and better understand how different beans respond to roasting.

The Result: A Diverse Palette of Flavours in Speciality Coffee

For example, a Kenyan coffee might be roasted lightly to highlight its bright acidity and juicy fruit notes, while a Sumatran coffee might be roasted slightly darker to bring out its earthy, spicy qualities. Each roast is carefully crafted to capture the essence of its origin, giving coffee drinkers a glimpse into the landscape and climate that shaped the bean.