Two, three minutes maximum are enough to drink an espresso, but pay attention&do not let it cool down!!! It could loose its TASTE and AROMA, and you would cancel in a moment the long process starting with the crop, classification and product analysis that brings coffee to be a friend during the whole day.
Everything starts with the crop, that is carried out when the fruits of the coffee have achieved the correct maturation and have a red colour. The fastest crop process is the "stripping", but in this way all the fruits are cropped, included those who did not achieve the maturation and those who matured too much. The other system is called "picking" that assures a better quality. Picking means hand crop of the mature fruits only.
Once the fruits are picked, the first treatment starts, and it can be dry or wet. Today the wet treatment assures a further selection of the fruits and a better homogeneity of the beans. After the wet treatment, coffee is ready to be roasted.
The best aromatic quality is obviously obtained with coffee ground before the use. An excellent espresso can be recognized from the appearance and taste: the cream must be brown - reddish with stripes, the body must be dense and the taste persistent. On the contrary, an imperfect espresso can be under extracted if it has a light cream with large bubbles, an inexistent body and a poor taste; or over extracted if it has a dark cream, a bitter taste, astringent with not much aroma.
To recognize a good bar espresso, it is enough to pay attention to the exam of the cup: the cream must have a beautiful light brown colour and be particularly dense, so that sugar can slowly descend and the cream can form again once the sugar is stirred.
The temperature of coffee is very important because the heat allows a better concentration of odorous substances that are different depending on the used blends.
In the mouth, with the association of olfactory and gustative sensations, professional people and people who are really fond of coffee can recognize the usually called "flavour": that means richness and taste corpulence. Moreover, being able to recognize a good espresso facilitates the preparation of a good home-made coffee, even if the results will obviously be different because different and less sophisticated are the machines used to prepare it.