In what scenario might a barista need to calibrate their espresso machine?

Calibrating an espresso machine is crucial when a barista starts using a new coffee blend because each blend has unique characteristics that can significantly affect the extraction process. New blends may have different levels of oiliness, acidity, and solubility that can alter the way water interacts with the coffee. Adjustments in grind size, dose, temperature, and extraction time are often necessary to optimize flavor and ensure that the resulting espresso meets the desired taste profile.

When transitioning to a different coffee blend, it is important to verify that the machine settings are suitable for extracting the best flavor and aroma from the new beans. This is essential for producing high-quality beverages that satisfy customer expectations.

In contrast, while cleaning the machine contributes to its longevity and correct functioning, it does not directly relate to the calibration process necessary to accommodate a different coffee blend. Serving customers is about beverage preparation and customer service, not calibrating equipment. Running out of water may lead to an inability to brew espresso but does not pertain to calibration; rather, it indicates a need to refill the machine before use.