An overextracted espresso exhibits either a white froth with large bubbles if the water was too hot or just a white spot in the center of the cup if the brewing time was too long.

• 过度萃取的浓缩咖啡不是出现由大型气泡所形成的白色泡沫，不然就是杯子中间出现一个白点；前者是由于水的温度太高，后者则是萃取的时间太长。