Espresso grinder test report

Over the past few years, we've tested numerous espresso grinders for home use and for the hospitality industry. Our testing protocol has evolved over time, collecting numerous data points for each.

In addition to the flavor potential in combination with high-quality and precise espresso machines, we test the particle distribution, dead space, consistency, temperature of the ground coffee and suitability as a single-dosing grinder.

In this article, we summarize our test points and link to this overview from the individual test reports.

The measurement and test protocol

Source material check

• Accessory check
• Grind 100g
• In-Out Test 1: grind 3 times 18g in, 30 seconds, measure output
• Take a 25 gram sample of the factory grind setting for particle distribution measurement (PVM)
• Check the factory grind setting: 18g coffee in - 45g out. Record the extraction time. (Espresso machine: San Remo Racer).

Output quantity, temperature, volume

• Set recipe: 18 in, 45 grams out in 25 seconds, with Apas Espresso
  
• Decibel measurement: grind 250g.

• We categorized the rating as follows:
• Below 80 decibels - positive/relatively quiet
• 80 - 90 decibels - neutral/rather loud
• Over 90 decibels - negative/loud

• Take a 25 gram sample of the set espresso for PVM
• Grind 5 x 18 grams of coffee, pause 20 seconds between each grind. Measure the temperature of the samples. Then rest for 5 minutes.

• Top below 30°C
• Good 30.1 - 35°C
• Medium/warm 35.1 - 39°C
• Negative/very warm 39.1°C
• Check the recipe: Grind 15 x 18g, taking 30 seconds between each measurement. Measure the temperature of the first sample and the last sample as well. From the last sample, extract 25g for PVM. Then let the grinder cool down.
• At that time, each grinder had a capacity of 1kg of coffee.
  

Adjustment test

• Recreate recipe Espresso : 18g in, 45g out in 25 seconds - sample for PVM
• Fine test (Ristretto) 1:1: 18g in, 18g out in 25 seconds - sample for PVM
• Coarse test (Café Creme) 1:6.6: 18 in, 120g out in 25 seconds - sample for PVM
• Reset to original espresso recipe: 18g in, 45g out in 25 seconds - take sample for PVM

Dead space and speed

• Checking the absolute dead space and removing residues by unscrewing and brushing.

Both the individual group tastings and the blind tasting at the end of the test series were conducted using an espresso tasting protocol based on the World Barista Championship evaluation form. Learn more about the espresso tasting protocol here.