What visual attribute characterizes an underdosed espresso?

An underdosed espresso is characterized by a yellow and watery appearance. This visual attribute occurs when the coffee dose used in preparation is insufficient to extract the desired flavors and oils from the coffee grounds. When the coffee is underdosed, the resulting brew lacks the intensity and richness typical of a well-extracted espresso. The yellow color indicates that there has been minimal extraction of the coffee's rich compounds, leading to a thin and diluted appearance. This is in contrast to a properly dosed espresso, which would show a balanced crema and richer color shades, often identified with deeper browns or marbled tones. A yellow and watery espresso signals that adjustments are necessary in the dosing to achieve a better flavor profile and overall coffee experience.