Coffee Grinding: Conical vs Flat Burrs

When beginning the research into grinding coffee often find themselves at a crossroads when choosing the right grinder for their sacred bean ritual. The debate between flat and conical burr grinders is not just a matter of taste, but a journey into the heart of coffee-making itself. These two warriors in the world of coffee grinding each bring their unique strengths and quirks to the battle. So, buckle up and let's grind through the differences, making sure your next cup of coffee is not just good, but ‘grind-tastic’!

Both flat and conical burr grinders have their loyalists who swear by their method of crushing beans. It's not just about turning beans into grounds; it's about unlocking flavour, controlling texture, and maximising the coffee experience. With a twirl here and a twist there, each grinder type promises a different path to that perfect cup. But what exactly sets them apart? Let's dive into the world of burrs and find out!

Flavour

When it comes to flavour, the type of burr can indeed make a subtle but noticeable difference. Conical burrs are celebrated for their ability to produce a more uniform grind at a slower speed, which can enhance the extraction of flavours, especially in espresso. The result? A full-bodied, nuanced cup of coffee.

Flat burrs, on the other hand, are known for creating a remarkably consistent grind, leading to a balanced and even extraction. This can often translate to a coffee with a clearer flavour profile, ideal for those who love their coffee with distinct, crisp notes.

Effects on Retention

Grind retention - the coffee that gets trapped in a grinder - is the nemesis of freshness. In this battle, conical burrs often have the upper hand, as their design allows for less space where grounds can hide and go stale.

Flat burrs, while excellent in grinding efficiency, can retain slightly more grounds within the burr set, potentially affecting the freshness of subsequent brews. It's a small, but important factor for those seeking the freshest coffee experience.

In these cases, it's best to look at what other inclusions the actual grinder has incorporated to reduce retention such as anti-static technology, a knocker or  bellows, etc.

Speed

Speed is where flat burrs often shine. They can grind beans faster than their conical counterparts, thanks to their larger diameter and aggressive grinding action. This makes them a favourite in busy coffee shops where time is of the essence.

However, for home enthusiasts, conical burrs' slower speed isn't necessarily a drawback. It’s more of a leisurely journey to a great cup, and some argue that the slower grind helps preserve the beans' delicate flavours. This is also why a manual grinder will typically have conical burrs. 

Heat

Heat generation during grinding can affect the flavour of coffee. Conical burrs generate less heat compared to flat burrs due to their slower speed, which is often seen as a benefit for preserving the beans' natural flavours. On the other hand, the faster speed of flat burrs can generate more heat, which might slightly alter the flavour profile, especially in finer grinds.

Noise

The morning coffee ritual shouldn't sound like a construction site. In terms of noise, conical burr grinders are generally quieter than flat burr grinders. This is due to the lower RPM (revolutions per minute) at which conical burrs operate. So, if you’re trying to keep the peace at home while grinding, conical might be your go-to.

Motor Power

The motor power required for each type of grinder varies. Flat burr grinders, due to their need for higher speed and more force to crush beans, often require more powerful motors.

Conical burr grinders can get away with less powerful motors, as the design of the burrs requires less force to grind the beans. This difference in motor power can also influence the grinder's longevity and energy consumption.

Customisation

Customisation is key in achieving that perfect grind. Flat burr grinders typically offer more precise adjustments, making them ideal for coffee enthusiasts who love to experiment with different grind sizes.

Conical burr grinders, while still offering a range of settings, might not provide the same level of fine-tuning. However, for most everyday coffee drinkers, the adjustability of conical burrs is more than sufficient.

Both burr types will have a number of variations in materials, size and specificity towards certain brew types. The norm is stainless steel, but an upgrade for a flat burr would be the Sung Sim Precision (SSP) aftermarket burrs that originate in Korea. These burrs can come in a number of variations depending on what you're looking for:

• High Uniformity Variant: made specifically for espresso
• Multipurpose/Unimodal Variant: for clean and nuanced flavour; low body and considered perfect for the modern espresso.

Durability and Maintenance

In the long haul, durability and maintenance play a big role. Flat burrs, due to their complex design and higher speed operation, may wear down faster and require more frequent cleaning and maintenance.

Conical burrs are generally easier to clean and maintain, with a design that's less prone to clogging. This means less time tinkering and more time sipping your favourite brew.

Pros & Cons

Conclusion

Choosing between a flat and conical burr grinder is like picking between a sports car and a luxury sedan - both get you to coffee heaven, but the journey is different. Flat burrs are fast, precise, and perfect for those who love experimenting with their brews.Conical burrs, on the other hand, offer a quieter, cooler grind, great for preserving the delicate flavours of your beans.

Ultimately, the best grinder is the one that fits your lifestyle, taste, and how you like your morning cup to unfold. So, whether it’s flat or conical, happy grinding and even happier brewing!