How long should a shot of espresso be used after extraction?

Using a shot of espresso within 30 seconds after extraction is essential for maintaining its optimal flavor profile and quality. After brewing, the espresso begins undergoing chemical changes, which can impact its taste and aroma. During the first half-minute, the flavors are at their peak due to the freshness and the emulsification of oils that contribute to the espresso's richness. Beyond this time frame, the crema dissipates, and the espresso may lose its ideal balance of acidity, sweetness, and bitterness. The taste can become increasingly bitter and less pleasant the longer it is left unused, as it continues to oxidize and degrade. Therefore, the recommendation to consume espresso within this 30-second window is grounded in preserving the sensory qualities that make a freshly extracted shot enjoyable.