Espresso: the 4 “M” rules

Espresso is the coffee preparation that requires more experience and skill. Preparing and serving your customers an Espresso and a perfect Italian Cappuccino is not easy because several factors determine the final result in the cup. It is essential for a professional barman to follow simple but important steps during the extraction, and perform a series of checks and activities of ordinary and routine maintenance of the equipment, according to a precise sequence. It takes knowledge, technique and meticulousness. A good blend of coffee can irreparably be ruined by improper use of equipment.
In short, the famous four “M” rules shall be followed:

1. The blend (“miscela”)

The use of a good coffee blend is the essential starting point for preparing a perfect Espresso. Caffè Cagliari for 100 years has been a guarantee of high quality coffee. Coffee is a hygroscopic product, so it is important to keep the packages in a dry cool place and free of smells. Before use, make sure the package has not been left open for a long period of time.

2. The grinder-doser (“macinadosatore”)

The grinder-doser is an essential operational tool that grinds the coffee beans into powder and delivers the correct dose for extraction of the Espresso.
The beans blend is poured into a hopper and then passes into the grinders; two burrs rotating at high speed grind the coffee beans. You can vary the grind degree by adjusting the distance between the grinders with a ring. The ground coffee is deposited in a container having a conveyor mechanism at the base and a dispenser that drops the predetermined amount of coffee into the filter.The coffee layer must then be firmly and evenly pressed (about 20 kg of pressure) to create a balanced counter-pressure during infusion.
The correct grinding can be verified by the extraction time (25 + 5 sec.), and this is an essential operation that can be done successfully only if you follow all the precautions and carry out a careful equipment maintenance, both daily and periodically. 

3. The espresso machine (“Macchina per espresso”)

The Espresso machine is the other key operational tool allowing us to make Italian Espresso, the drink that the whole world envies us.This machine is equipped with a rotary pump that takes water from the waterworks and brings it to a pressure of 9-10 atmospheres in the boiler, a tank where a heat exchanger brings and keeps the temperature at 100-130° C and pressure at 1 to 1.2 bar, together with the steam. Boiling water is then sent to the dispensing unit, where a shower head placed under the unit distributes it evenly over the coffee layer for infusion and subsequent dispensation at a temperature of 88-92°C and a pressure of 9-10 atmospheres.
The water purifier
The coffee machine should be used with adequately treated fresh tap water, around 9 French degrees, to prevent the formation of limescale on the inside. In fact, apart from creating thermal imbalances and wasting energy, it reduces the machine performance and affects the yield of coffee.
The technician then places the water treatment unit between the water network pipe and the coffee machine; the water purifier is an essential device, round-shaped, that allows you to purify, or soften tap water, by using resins (tiny balls) that trap the excess calcium and magnesium salts contained in water.


Despite the fact that nowadays highly sophisticated equipment is available, the barman’s expertise and manual skill are still key components in making a perfect Italian Espresso or Cappuccino.
Only with training, experience and passion the bartender is able to adjust and manage the equipment at its best, and to carry out proper maintenance in order to achieve perfection in a cup and to offer his customers a professional service.

For more info about checking and maintenance of the equipment, we suggest you to ask local Caffè Cagliari distributor about coffee training courses schedule.