Used coffee tablet:

Inspect the look and structure.

If the espresso has been brewed correctly, the coffee tablet:

* will be slightly damp

* keeps a structure — as plasticine

* The portafilter keeps its shape, and doesn’t collapse.

* Breaks, but does not crumble.

Correcting mistakes:

A dry and crumbling tablet means the grinding is too coarse, the amount of coffee too large, or the tamping too strong.

A tablet that’s “spreading” means that the grinding is too fine, the amount of coffee is too small, or the tamping is too weak.

Cremá (foam):

Inspect the: color, density, features of structure and stability.

Cremá is formed in during the extraction: proteins, fats and high-molecular sugar turn in emulsion; allocated gases, entering with emulsion interaction, make foam. The characteristic color is due to the caramelization of sugars and oxidation of phenols.

If the espresso has been brewed correctly, the crema will:

* Have a reddish-brown color (colors of a nutshell of a filbert);

* Have a thickness of over 2 mm;

* Be continuous, without any holes or ruptures

* Not have any large bubbles

* Be steady, and keep for over 2-3 minutes

* Be “live”, it’s restored after drink hashing

* Have dark brown strips or specks (like a tiger or a leopard’s skin).

Correcting mistakes:

A light brown color or small density of foam is due to insufficient extraction. Usually it’s for the following reasons: The grinding is too coarse, the tamping is insufficient, or the temperature or pressure is below normal.

A dark brown color and appreciable bubbles is a sign of excessive extraction. The grinding was too fine, the tamping temperature was too high, or the pressure was above normal.

A dark color with shades of gray or an earthy color is a sign of a considerable quantity of robusta coffee in an espresso blend.

A non-uniform friable foam means uneven tamping.

Aroma:

Inspect: both positive and negative characteristics.

Good aromas would be roasted, fruit, or flower. Examples of bad ones include: smoky, prorancid, grassy, straw, or rotten.

Taste:

Inspect: both positive and negative characteristics.

Good tastes include: sourish, wine, citron, chocolate, pleasantly bittered, flower, and balanced.

Bad tastes include: astringent, earthen, mealy, wooden, sour, medicine-y, and pith.

Poor smells and the flavoring characteristics shown in espresso can be the result of both the use of poor-quality beans and a consequence of unfair care of a coffee grinder and espresso machine.