Coffee grinder and ground coffee for different ways of making coffee

23/02/2015 10:48:00
Coffee is undoubtedly the most cultivated drink in the world: every day over 100 million bags of coffee beans are used.
The taste and the pleasure deriving from coffee are subjective and this has created several ways and habits of coffee making in numerous countries.

Italian espresso coffee is universally acknowledged as having the best technique of extracting, from ground coffee, the excellence of aromas, fragrances and flavour.

This all Italian invention which we are so proud of has invaded all countries. So much so that economists tend to use coffee consumption as one of the parameters to measure the quality of life and its increase in developing countries.

Obviously “Italian espresso coffee” requires special equipment (espresso coffee machines), a preparation technique as well as particular procedures that are not going to be tackled in this article. If you are interested in improving your knowledge of ’”Espresso italiano” or want to make your barista business profile more professional, we would like to suggest you read the other articles on Coffee culture or purchase the book “The espresso coffee production system”.
The various grinding levels and coffee preparation methods

Extraction grind
Turkish coffee

-Middle East,
-Greece and the Balcans.

Espresso fine grind
Italian espresso,
it is considered a delicatessen in all countries.

Medium fine grind
Moka, another typical Italian tradition in the domestic sphere, also used in many other Latin origin language countries.

Medium grind
Press filter,
Northern Europe, United Stated and other countries.
Coarse grind
Northern Europe,
United States and other countries.

Coarse grind
Boiled coffee
Northern Europe,
United States and other countries.
The coffee grinder
In order to obtain the various grinds, according to the kind of coffee one wishes to make, it is necessary to use a coffee grinder (our grandmothers used to have the typical manual grinder).

Nowadays numerous types and technologies are available for grinding and grind regulation (regulation in the distance between burrs) and according to the amount of ground coffee required in a day for bars, restaurants, hotels.

For Italian espresso coffee, grinders are necessary as they grind the exact amount for one coffee (approx. 6-7 gr.).  This is important as Italian coffee, as advised previously, requires pre-requisites.

Picture: Coffee grinder On Demand Baratza Fortè 230V LF code 1252479
The two technologies of coffee grinding
Conical burrs (600-800 kg)
- for large consumption.
- to be replaced between 600 and 800 kg of ground coffee.
- Number of rotations /min = 400/700 to prevent overheating of ground coffee with large consumption.
Flat burrs (300-400 kg)
- for consumption of 3-4 kg
- Number of rotations /min = 900/1400
- to be replaced after approx. 300-400 kg

The main difference between the various coffee grinders lies in the technology of their conical burrs (for large consumption) and flat burrs for limited consumption and their number of rotations per minute.

The life duration of burrs also depends on the quality of the material they are made of, the working precision and the kind of thermic treatment they undergo.

Burrs are available from LF store are strictly Made in Italy. Although you will also find on the market low cost Chinese manufactured burrs.

It is important to know that the friction between the burrs and coffee beans produces heat which will cause it to  wear out with time (increase of friction/heat).  In addition the grease contained in the coffee sticks to the burr’s teeth increasing the friction and changing the resulting grind.

Important: the temperature of ground coffee cannot exceed 50°C otherwise the aromas evaporate before the extraction and there is the risk of “burning” the coffee (even more so for espresso coffee!).

Check both grind measure (if it changes with time, for instance) and temperature.
Clean your coffee grinder on a regular basis (every 24/48 h according to the amount of ground coffee).
Specific products are available for the cleaning of burrs.

When you notice that the ground coffee temperatures increase despite the burrs being cleaned or the grind is not perfect, it means that you have to replace your burrs.

Remember that for espresso coffee you have to use from 6.5 to 7.5 g of ground coffee.
Dosing is important for a good result and it has to be always within the above mentioned limits. Dosing can be made manually using measuring scoops and precision scales but it is advisable to use coffee grinders which, once they have been calibrated, are independently set to the right dosage.

The information and the images in this article were taken for the book La filiera del caffè espresso published by Bazzara.

For professionals and for espresso coffee lovers we suggest reading the articles contained in the section called "Coffee".  Also watch the videos on the correct use of equipment in coffee making and on latte art in the section  "Video".