What Causes Espresso Crema to Dissipate Quickly? What Does Crema Mean? Is Thicker Crema Always Better?

Understanding Espresso Crema: Beyond the Coffee's Flavor

Beyond the flavor of the coffee itself, crema richness is a key focus for most friends when extracting espresso. This might be to meet the needs of coffee latte art, or it could be influenced by concepts planted by bean merchants when promoting their products. From time to time, customer friends ask FrontStreet Coffee how to extract richer crema. So today, FrontStreet Coffee will explain in detail how to extract rich espresso crema.

The Truth About Crema Thickness

But before that, we need to know that espresso crema is not necessarily better when thicker. Although crema is called "crema," it's actually bubbles filled with carbon dioxide. Carbon dioxide cannot directly affect the taste quality of a coffee. What we commonly say about crema bringing more aroma and richness to coffee actually comes from the aromatic substances in the insoluble oils that trap the carbon dioxide, as well as the effect of fine particles mixed in the crema. The main factor determining crema thickness is the carbon dioxide content of the beans used during extraction (followed by insoluble oils). When there's more carbon dioxide in the beans, the espresso will have richer coffee crema under proper extraction. Therefore, crema thickness cannot directly affect flavor. In other words, as long as you use coffee beans with rich carbon dioxide content for espresso, you can obtain rich crema!

The Impact of Roast Level

The primary factor affecting the carbon dioxide content of beans is their roast level! When beans are roasted darker, their expansion rate becomes higher, allowing them to hold more carbon dioxide produced during the roasting process. We can clearly see the impact of roast level during the bloom stage of pour-over coffee, as the dome of dark-roasted beans is much larger than that of light-roasted beans. Additionally, with deeper roast levels, oils that overflow to the bean surface also increase. This makes the extracted espresso crema more stable and longer-lasting. Therefore, when we use darker roasted coffee beans, the crema becomes richer.

Freshness and Carbon Dioxide Content

Of course, the freshness of the beans also affects crema richness. Because after beans are roasted, carbon dioxide and oils continuously escape from the bean surface. Coffee beans closer to the roast date mean they retain more carbon dioxide, naturally allowing for richer crema extraction! The reverse is also true. It's worth noting that although using freshly roasted coffee beans can extract large amounts of crema, the excessive carbon dioxide makes it difficult for the crema to maintain for long periods. These bubbles will quickly break and then clump. Therefore, to allow crema to "last forever" and to reduce the obstruction caused by carbon dioxide during extraction, people generally let espresso beans rest for a while to degas. This makes extracting delicious flavors easier and crema more stable!

The Role of Robusta Beans

On this basis, if you want even richer crema, we can also incorporate the use of Robusta beans. Because crema richness is not only affected by carbon dioxide content but also by the genetic factors of bean varieties. Under the same roast level, Robusta's crema will be much higher than Arabica's. However, due to its slightly inferior flavor, most merchants use blending methods to balance out the taste of Robusta coffee beans, only capturing its advantage of rich crema. For example, FrontStreet Coffee's commercial blend is like this!

Final Considerations

The final point to note is that all the above methods are based on conventional, correct espresso extraction. When we use too coarse grinding or extract too much liquid weight, the crema thickness will be reduced. Therefore, this point also needs attention!

Important Notice :

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