1. Coffee Volume
Minimum requirement is for grinders hopper capacity to accommodate 60 grams of coffee beans. The volume of the hopper must be sized in proportion to the grounds receiver’s maximum capacity as stipulated by the manufacturer.
2. Temperature ground coffee
The coffee grinder must under no circumstances heat up coffee more than maximum 10 degrees Celsius. Test will be performed as described: Measuring temperature of the coffee beans before grinding and measuring of the temperature of the ground coffee immediately after grinding. Volume to be tested is 60 grams of coffee.
3. Grind Retention
The coffee grinder must be able to dispense ground coffee without retaining too much coffee. Too much will result in uneven dosing and affect brew ratio and coffee quality in the cup. The test will be performed as described: Grind retention Inn/Out.
A volume of 30 Gram will be grinded 10 rounds and weighed Inn/Out. The average retention must not be greater than 1,5 grams =2,5%
A volume of 60 Gram will be grinded 10 rounds and weighed Inn/Out. The average retention must not be greater than 3,0 grams =5%
Total retention. The sum total of all grinds contained inside a grinder. The test will be performed as described: A volume of 60 Gram will be grinded 10 rounds and all coffee residues will be weighed. The sum total must not be greater than 3,0 grams =5%
4. Grind Quality
The coffee grinder must be able to produce a prescribed grind distribution within +-5% of the ECBC Filter grind standard.
|ECBC Filter grind distribution standard|
|Size Range (μm)||Percent (%) by weight|
Grind distribution will be assessed using lab equipment from Hosokawa Alpine (eLS 200). Grind distribution tests will be made using the Swiss method. For this test, 25-gram coffee samples are tested individually sieve-by- sieve at 3000 pascals for three (3) minutes. This method will elucidate the ability of the grinder to meet the above stated grind distribution and determine if distribution meets the requirements for fines minimum
(20% < smaller than 425 µm).
5. Uniformity of Performance
To assure the grinder model is both consistent in grind settings and reliable, it will be tested for uniformity of performance. For this test, a minimum of 6kg coffee will be grinded and grind size distribution will be analysed 3 times on same setting (Filtergrind). Maximum deviation is +- 5% in grind distribution in these 3 tests. Sample for analysing will be collected from every second kilo of coffee grinded
(after 2 kg, 4 kg and 6 kg)
6. Uniformity of Extraction
Ability to produce grinded Coffee that can be brewed to acceptable extraction.
Using ECBC/SCA Gold Cup standards, ground coffee will be brewed with the following standards:
- Contact time water and coffee 4-6 minutes,
- Water temperature 92-96 C,
- 60 grams of coffee to 1 litre of water = 1:16,66 Ratio.
The test will be performed on an approved auto drip brewer for domestic use, and analysed using a refractometer to ensure an extraction between 18 – 22%. And TDS (total dissolved solids) between 1,30-1,50%.
7. Operating Manuals and other Instructional Materials
The minimum requirement for certification is that all instructional materials including operating manuals, pamphlets, and promotional items supplied with the grinder. Proper grinding instructions must be included, specifically some suggestion of a coffee/water ratio and cleaning instructions. The ECBC will note errors and propose necessary changes to the grinder manufacturer. A grinder submitted for testing will not be considered ready for ECBC approval before these matters are resolved.