Choosing Right Grinder: Conical Burr vs Flat Burr

Grinding Mechanism: Conical Burr vs Flat Burr
Understand Grind Size Consistency
Heat Produced Matters
Taste Difference Between Conical Burr vs Flat Burr
Subsidiary Factors for Choosing Grinder

Grinding Mechanism: Conical Burr vs Flat Burr

The primary purpose of a coffee grinder is to increase the surface area of coffee beans to make them suitable for brewing. Unlike blade grinders which use blades to cut the coffee beans, burr grinders use two abrasive surfaces, called burrs, to crush the beans. One burr remains stationary, while the other rotates. Coffee beans are fed between these burrs, and as they are crushed, they are broken down into particles of the desired size. The distance between the two burrs can be adjusted to control the grind size.

Conical Burr

Conical burrs have a cone-shaped grinding mechanism where one burr is placed inside the other. The outer burr has a ridged surface, while the inner burr is shaped to fit snugly inside the outer burr. Coffee beans are fed into the gap between the two burrs, and as the inner burr rotates against the outer burr, the beans are crushed between the ridges.

Flat Burr

In a flat burr grinder, the grinding mechanism consists of two flat, parallel, and horizontal burrs placed one on top of the other. Coffee beans are fed into the gap between these two burrs, and as one rotates against another, the beans are crushed and broken down into smaller particles.

Understand Grind Size Consistency

The consistency of grind size is crucial for coffee quality. Conical burrs can produce a slightly varied particle size distribution due to their design, with ridges on the outer burr. While efforts have been made to reduce this variability, some differences may still exist. In contrast, flat burrs offer a very consistent grind size because of their flat and parallel alignment, resulting in more uniform particle sizes and, consequently, more consistent extraction.

Heat Produced Matters

Excessive heat is a critical factor that can impact flavour and aroma. Conical burr grinders generate less heat compared to flat burr grinders. Conical burrs crush beans between cone-shaped burrs with less surface contact, preserving coffee’s aromatic compounds and oils for a more flavourful cup. In contrast, flat burr grinders have more direct contact, potentially generating more heat that may affect the coffee’s sensory qualities by evaporating volatile compounds and oils.

Taste Difference Between Conical Burr vs Flat Burr

The taste difference between cups of coffee from each burr grinder mostly depends on their consistency. As mentioned above, flat burr grinders generally produce more uniform and even coffee grounds. Therefore, flat burrs will give you more balanced and consistent shots of espresso. However, in some circumstances, where you aim to avoid under and over-extraction, a diverse range of coffee particles from conical burrs may provide you with a more complex cup of coffee. Additionally, when discussing the coffee’s aroma, conical burr grinders may have an advantage over flat burr grinders, as they generate less heat during operation. Excessive heat can cause volatile compounds, responsible for aroma, to escape more readily from the coffee beans.

Subsidiary Factors for Choosing Grinder

There exist additional distinctions between conical burrs and flat burrs. Nevertheless, these aspects are subsidiary considerations when selecting the right grinder, as they do not heavily impact the flavour of coffee.

RPM: Flat burr grinders require a higher RPM to ensure that all the grounds are forced out the sides. Because they use a powerful motor, they grind coffee beans relatively faster but make more noise.

Retention: Conical burrs can have lower retention of ground coffee between the burrs, which means that less coffee grounds get trapped and remain in the grinder after each use. This can be especially important for those who want to minimise waste and keep their grinder clean.

Affordability: Conical burr models generally offer more budget-friendly options, while flat burr grinders tend to be slightly more expensive because of their precision engineering and advanced features.

Conclusion

Choosing the right grinder based on the coffee bean you use and how you want to present it, is the key for the perfect brew. Each grinder type offers a distinct approach to flavour extraction, inviting you to shape your coffee experience according to your preferences. As you embark on this flavourful adventure, remember that the heart of a great cup of coffee lies in your passion and commitment to the craft.