What taste might a customer experience if a shot is left to sit too long?

When coffee, particularly espresso, is left to sit for an extended period, it can develop a bitter and burnt taste. This occurs due to the continued extraction of compounds from the coffee grounds. As the shot sits, the flavors continue to evolve, often leading to over-extraction where undesirable bitter compounds become pronounced.

The heat and time also contribute to flavor degradation, further enhancing the burnt qualities associated with over-sitting espresso. Unlike a fresh shot that showcases a bright and balanced profile, a shot that has been sitting will lack freshness and complexity, resulting in that harsh bitterness which can be unpleasant to experience. Understanding this aspect helps in ensuring that beverages are served at their peak flavor profile, enhancing overall customer satisfaction.