Conical Vs Flat Burr: Which One?
I was watching a video on the conical vs flat burr debate that remains at the center stage in the growth of the specialty coffee industry. And I must say I was excited by the insights in the clip. Perhaps you too would want to understand how these two burr types differ in their functioning and why you might prefer one over the other. Well, this article got your back with exactly that.
A conical burr is a cone-shaped, easy-to-use burr that yields a bimodal distribution of coffee while a flat burr features two donut-like burrs with razor-sharp edges and produces a unimodal distribution of coffee grounds.
What is a Conical Burr?
The debate about conical vs flat burr is empty without first describing each of these tools.
A conical burr is a cone-shaped burr type consisting of an outer serrated burr and a cone-shaped center burr. You can often find it in commercial and home grinders, especially manual grinders.
When you switch on the grinder, the center burr spins while the outer serrated burr remains stationary. As this inner burr spins, its sharp edges move the whole coffee beans into the grinding area to crush them into small pieces.
The distance between the inner burr and the outer burr determines the size of the resulting grounds. If the two are closer, then the grind becomes finer. Nonetheless, the shape of the burrs enables them to produce uniform grinds with high-level grind size control.
When it comes to grinding particle distribution, conical burrs yield a bimodal distribution of coffee grounds. If you take the coffee grounds from the conical burrs and put them under a microscope or sifter, you will observe two distinct particle size sets; large and small.
The size affects the brewing process as the finer grinds extract faster than the large ones. As a result, you might get an unbalanced brew in taste and flavor.
Conical Burr Pros
- High-level grind size control
- Lower retention rate due to their vertical position in the grinder and gravity
- Yields Minimal heat
- Low noise
- Less expensive
Conical Burr Cons
- Bimodal distribution leads to imbalanced flavors
What is a Flat Burr?
The shape of flat burrs is quite different from that of conical burrs. This espresso frontier features two donut-like, serrated burrs with razor-sharp edges, typically aligning horizontally with each other. In most cases, you can find flat burrs in commercial espresso grinders and upper-level home grinders.
When you feed whole coffee beans into the grinder, the burr’s inner teeth grab them and force the beans through to the area where these teeth are more precise and frequent. But unlike the conical burrs whose grinds exit through the bottom, the flat burr releases the coffee grounds through the sides.
Since the coffee beans stay longer with flat burrs than with conical burrs, friction is high, generating more heat. Besides, spinning the flat burrs takes a strong motor, which yields a high-pitched noise.
The best part is that flat burrs yield unimodal distribution. If you happen to examine the grounds using a microscope, you will see all the grinds having the same size.
With this uniformity and precision, you can pull a consistently gritty, classic, and thick shot since all the grinds will have the same extraction rate.
On the flip side, flat burrs have a higher retention rate. That’s mainly because of the positioning of the burrs within the grinder and how its grinds come out.
Since the burrs are aligned horizontally, they do not get any help from gravity but rely on the motor entirely. Besides, the grinds exit from the sides, leading to more grind remains on the burr’s teeth.
Flat Burr Pros
- Unimodal distribution
- Enables higher extraction
- Higher espresso creativity and variability
Flat Burr Cons
- Generates high heat
- Makes more noise
- High retention rate
Best Burr Coffee Grinder
If you plan to buy a burr coffee grinder, check out these 5 leading options. You might find what meets your expectations and preference. But, you should not also forget about the Rancilio Rocky and the Sette 270 coffee grinders.
1. Baratza Virtuoso Plus Conical Burr Coffee Grinder with Digital Timer Display – Best Overall
From the Baratza Virtuoso, you get its updated version, the Baratza Virtuoso plus, which is an automatic burr grinder. This easy-to-use grinder consists of 40mm stainless steel burrs driven by a 550 RPM (Revolution Per Minute) motor.
Baratza virtuoso plus further has a digital timer and display, making the grinding process simpler. With Its 40 grind settings, ranging from 200 to 1200 microns, you can use any brewing style except cold brew and Turkish coffee.
This burr grinder stands out more because of its commercial-quality burr design and motor, which harmoniously work, reducing heat and friction.
- Consistently grind beans
- Reduces heat and friction
- Works for various brewing styles
- Digital timer display
- Not ideal for cold brews and Turkish coffee
2. Baratza Vario Flat Burr Grinder – Best for All Brew Styles
This automatic flat burr grinder offers professional quality for home brewers but still works best for small commercial settings. Vario flat burr has a 54 mm professional ceramic flat burr, power-driven by a 1350 RPM motor.
Its wide burr size enables consistent grinding, with its output speed reaching 2.2 g/s. The burr grinder also features 230 grind settings and has an in-built portafilter holder that handles any portafilter size.
- Wide range of grind settings and adjustments
- Professional performance
- Pre-set grind programming
- Slightly complicated
3. Bodum Bistro Burr Coffee Grinder – Best Pocket-friendly Grinder
If you need something budget-friendly but exceptional than the blade grinder, the Bodium bistro burr grinder might be the best choice. The easy-to-use automatic burr grinder features 35 mm stainless-steel conical burr grinders powered by a 720 RPM motor.
Bodium bistro has 12 grind settings, making it an ideal option for pour-over or drip brewing. Its borosilicate glass grounds vessel comes in handy in eliminating static for easy cleanup.
Another good feature is its friction clutch, which alerts you of any stones found in the grinder. Through that, you avoid damaging the burrs.
- Attractive design
- Ease of use
- Easy cleaning and maintenance
- Fewer grind settings than other products
- Not ideal for espresso
4. Baratza Encore Conical Burr Coffee Grinder – Best entry-level Burr Grinder
Barista-approved Baratza encore is among the leading entry-level coffee grinders currently on the market. The burr grinder consists of 40 mm stainless steel conical burrs driven by a 550-RPM motor.
Although this burr grinder is not so fast compared to other grinder options, its slow speed leads to a good grind consistency and low heat.
Further, the Baratza Encore features 40 grind settings, ranging from 250 to 1200 microns, making it a better choice for manual brewing methods. You may also use it for espresso grinds though it doesn’t provide more flexibility.
- Excellent grind consistency
- Intuitive functionality
- Lacks timer function
- A bit pricey for some first-time brewers
5. Rancilio Rocky Espresso Coffee Grinder – Best Burr Grinder for Espresso
Rancilio Rocky’s design makes it an ideal choice for espresso grinding. This automatic flat steel burr grinder comes with 50 mm flat steel burrs with a 1725-RPM motor. The feature enables it to grind coffee beans in large quantities.
Rancilio rocky also has 55 grind settings, well-calibrated at the end of the scale. Its standard model comes with a plastic bean hopper. On the other hand, the rocky SD model features a portafilter holder.
- Excellent grind consistency
- Powerful performance
- Ease of use
- No hands-free grinding without a timer function
So, the question on conical vs flat burr, which one should you buy? It all narrows down to your unique needs and wants. Both burrs yield quality results, with each having its strengths and weaknesses. However, if you are working on a budget, l would prefer you buy the conical burr grinder. You will still get some quality models at an affordable price.
However, if the issue on conical vs flat burr is too heavy on you, why don’t you try both of them. You will be surprised to know how superior the two coffee grinders are.