What is an indication of a poorly pulled espresso shot?

A poorly pulled espresso shot is indicated by distorted and dark crema. This condition often results from factors such as uneven extraction, improper grind size, or incorrect tamping pressure. In an optimal shot, crema should have a rich golden-brown color with a smooth texture, which indicates that the coffee has been extracted properly, balancing flavors and oils effectively.

When the crema appears distorted or overly dark, it usually means that the coffee was either over-extracted or under-extracted; this can lead to a bitter or harsh taste, which lacks the nuanced flavors intended for a well-prepared espresso. Thus, the appearance of the crema serves as an important visual cue to assess the quality of the espresso shot.