8 REASONS TO SWITCH TO CONVECTION RIGHT NOW
8 REASONS TO SWITCH TO CONVECTION RIGHT NOW
- Stability – Convection roasters are less affected by external factors, such as ambient temperature and humidity. The air inside is circulated and reheated, instead of mixing with the room air. These roasters are insulated from the external environment by a thermal insulation layer, minimizing the impact of temperature fluctuations in the room. Convection roasters do not accumulate thermal energy throughout the workday, which is an effect seen in conduction roasters after several hours of operation, requiring adjustments to the roasting profiles.ㅤ
- Repeatability – A convection roaster more easily replicates set profiles, both manually and automatically. Roasters do not need to adjust for the inertia of metals; the response is very quick, almost instantaneous. Convection roasters dissipate almost no heat warming up the metal; every kilowatt of energy goes directly to heating the coffee. Also, critical checkpoints for roasting, such as the start of the crack, development time, and the start of Maillard reactions, are repeated under the same conditions with minimal deviations.
- Defect-Free Roasting – With convection roasting, the primary factor that causes defects is eliminated: metal heated above 300 degrees Celsius where it contacts the beans, which is typical for conduction roasting. Inside convection roasters, stainless steel is used, which does not accumulate heat and quickly dissipates energy. During the roasting process, an air layer forms between the coffee and the metal, reducing the overall contact time with the metal. The metal temperature inside the roasting chamber is equal to the bean temperature and never reaches critical levels. Coffee roasted in convection using the “fluid bed” technology ensures uniformity and prevents scorching of individual beans, which is a common issue in conduction roasters.
- Even Roasting – The design of a rotating drum with paddles cannot ensure proper mixing of the coffee mass or prevent prolonged contact with overheated metal, unlike the Fluid Bed technology. In Fluid Bed technology, the coffee is evenly distributed on a horizontal grid and actively stirred by air flows during the roasting process, ensuring even roasting.
- Better Technology for Espresso Roasting – It is commonly believed that convection is superior for roasting coffee intended for espresso (medium to dark roasts). Convection provides a dense, full-bodied, and sweet cup. The caramelization of sugars in the roasting process with convection roasters is more delicate, bringing out the coffee’s natural sweetness. When preparing espresso, the extraction time is short, so uniformity in roasted coffee is essential. Only active convection can roast not only the outer shell of the coffee but also reach the core of the bean in a short time, resulting in a uniform coffee structure with consistent extractability.
- Pure and Sweet Taste for Light Roasts – Convection is ideal for revealing the natural sweetness of coffee, especially for naturally processed beans. With light roasting, all coffee varieties, regardless of the processing method, are cleaner (thanks to even roasting and the absence of defects), fruitier, and have distinct characteristics.
- Enhances the Flavor of Fine Commercial Coffee – Fine commercial coffee is often less acidic than specialty coffee. When working with such beans, it is essential to maximize the natural sweetness through caramelization without over-roasting. This type of coffee is frequently roasted for espresso, and convection roasters are better suited for medium to dark roasts. The absence of roasting defects in convection roasters also has a positive impact on the quality of fine commercial coffee in the cup. The roast will be even and free of burnt beans, even if the green beans had low initial moisture.
- Twice the Productivity – On average, convection roasters roast 6 batches per hour. In contrast, conduction roasters only manage about 3.5 batches per hour. The average roasting cycle is just 6-8 minutes, which is 30-40% faster than in conduction. This efficiency is achieved because convection can deliver energy directly to the entire surface of the bean, not just where it’s in contact with the metal. Also, the air simultaneously interacts with all the beans in the batch. Additionally, convection roasters essentially lack a preparation protocol between batches since the loading temperature doesn’t affect repeatability or coffee quality. Convection roasters can be loaded to 100% of their stated volume, regardless of the roasting style, without compromising quality. In conduction, the recommended coffee loading volume is 80-85% of the stated capacity for espresso roasting.