Ideally for good espresso you need a good espresso blend. The best coffee beans are blended to achieve smoothness, sweetness and aromatics desired in espresso. The blend must be fresh and recommend using within 7 days of roasting.
Roasting
Roasting coffee too dark will result in a bitter, tasting charcoal brew. Roasting lighter will preserve the aroma and sugars.
Grinding
To achieve an extraction time of between 25-30seconds the grind must be frequently monitored throughout the day. Changing the pressure of the tamp will not compensate for the grind that has become too large or small.
Dosing
Grind and dose on demand with fresh coffee if you want to achieve peak flavours. Grind only what is necessary for one shot dose, distribute the coffee evenly into the porta-filter, tamp and brew.
Tamping
Tamp evenly with about 2.5kg of pressure, then again with about 13.5kg of pressure, and polish (twist) 720 ° with 9 kg pressure.
Water
Filtered water is best used for espresso.
Water temperature
Should be at a stable 92-96° c.
Water pressure
The water forced through the espresso should be between 9 and 10 atm. This pressure is responsible for the development of the crema.
Porta-filter and basket
Ideally the porta-filter should remain the same temperature as the water used to brew the coffee. Therefore it should remain in the group head.
Machine cleanliness
Cleaning the machine, basket, and porta-filter regularly will eliminate any rancid taste.
Grinder maintenance
Burr blades should be swept clean everyday. Brush out excess grounds between shots that get stuck between the burrs and dosing chamber. Replace burrs at least yearly so that they produce coffee granules with maximal surface area.
Environment
The grind size must be changed throughout the day to achieve a brew time of 25-30 seconds since coffee is hydroscopic (absorbs moisture). Humidity has more of an affect on coffee than temperature, but it is important to avoid exposing the coffee to high temperatures until brewing.
Espresso cup
The cup should be pre-heated and have thick walls and a narrow mouth to retain heat and aroma.
Have a go!
