What Is Coffee Crema?

Introduction

Coffee crema, often simply referred to as "crema," is a thick, creamy, tan-coloured layer that forms on the top of a freshly brewed shot of espresso. It is a distinctive and desirable characteristic of a well-prepared espresso, especially for espresso enthusiasts and baristas. Crema is a visual and sensory indicator of the quality of the espresso and the freshness of the coffee beans. Here's what you need to know about coffee crema:

1. Formation: Crema is created during the espresso extraction process when hot pressurised water comes into contact with finely ground coffee beans. The pressure forces oils and gases out of the coffee grounds, and these substances then emulsify to form the creamy layer on top.

2. Appearance: A well-formed crema has several visual characteristics:

• It is thick and velvety, with a consistency resembling frothy cream.
• The colour can range from light tan to reddish-brown, depending on the type of coffee bean and roast level.
• Crema should be uniform and cover the entire surface of the espresso shot.

3. Aroma: Crema contributes to the aroma of the espresso, releasing fragrant compounds as it forms. The aroma can be nutty, slightly sweet, and carry hints of the coffee's flavour notes.

4. Taste: Crema is more than just a visual component; it also contributes to the taste and mouthfeel of the espresso. It can be slightly bitter, which balances the overall flavour profile of the shot. The crema's creamy texture enhances the coffee's overall body.

5. Freshness Indicator: The presence and quality of crema are often used as indicators of coffee freshness. A thick, long-lasting crema typically suggests that the coffee beans are freshly roasted and ground. As coffee beans age, their ability to produce crema diminishes.

6. Crema Stability: Crema is relatively short-lived and begins to dissipate shortly after the espresso shot is poured. A high-quality crema should remain stable for a few minutes, which indicates that the espresso was properly extracted.

7. Espresso Shots: Crema is most commonly associated with espresso shots, where it is a defining feature of a well-pulled espresso.

Conclusion

To achieve a good crema, it's important to use fresh, high-quality coffee beans, grind them correctly, and ensure proper extraction when brewing espresso. Baristas often pay close attention to factors like grind size, tamping pressure, and water temperature to achieve the ideal crema. Crema can also be used as a visual guide to diagnose issues with espresso extraction, such as under-extraction (thin or weak crema) or over-extraction (too much crema with a bitter taste).