What Is Crema on Espresso? (And Why It Matters)
Crema is the reddish-brown, foamy layer that sits on top of a freshly pulled espresso shot. It forms when CO₂ dissolved in the coffee bean is released during high-pressure extraction and emulsifies with the coffee’s natural oils. Crema is unique to espresso — it requires 9 bars of pressure to form. You won’t get real crema from a moka pot, French press, or drip coffee. Why Crema Forms Coffee beans contain dissolved CO₂ from the roasting process. When you force hot water through finely-ground coffee at 9 bars of pressure, two things happen simultaneously: ...