Why is it so hard to get the perfect coffee crema for espresso?

The crema has to be sturdy enough to withstand the weight of a teaspoonful of granulated sugar for a few seconds before it begins to dissolve.

The experts are aware that the crema on top of a decent espresso has to be just right. Espresso is much more than simply a little cup of coffee due to a number of factors, including the aroma, flavor, and texture of the small coating of foam that tops the beverage. But what is it exactly that makes the espresso so unique, and how can one ensure that it comes out just right?

The “Certified Italian Espresso”

Espresso is the most effective method for wringing out coffee beans for the best taste they can provide. Italian coffee makers establish rigorous standards in order to provide the title of “Certified Italian Espresso” to the coffee that is traditionally consumed across the nation. This includes the ideal crema, which has a foam that ranges from hazelnut brown to dark brown, has light reflections that are yellow-brown in color, and has a very fine and dense structure without bigger or smaller bubbles.

The oils in coffee provide the best foam

The “coffee oils,” as they are often referred to, are primarily responsible for the crema in coffees. These are essentially water-insoluble compounds, thus only trace amounts are absorbed by the coffee during brewing. Although there is a significant difference in the way that Italian espresso and filter coffee are prepared, sufficient quantities are still able to form the crema: in espresso, the hot water is not allowed to simply flow through the coffee powder; rather, it is forced at high pressure through the powder while it is compressed in a sieve.

This method is likewise more effective in dissolving the various sugars and proteins that are components of the crema, and it is used for the coffee powder. These insoluble compounds swirl about in the water when the pressure is raised, creating the tiniest foam bubbles possible. The aromatic foam eventually settles at the top of the cup, where it may be seen.

The science of the perfect crema

The crema is primarily responsible for the typical velvety feeling that one feels on the tongue after drinking espresso, and it also makes a considerable contribution to the rich flavor of the beverage. Multiple elements need to converge in precisely the right way before an espresso can boast of having the ideal crema.

The temperature of the water should not be very hot or cold; generally speaking, a temperature of around 190 degrees Fahrenheit (88 degrees Celsius) is thought to be ideal. The water pressure that is used during the brewing process has to be sufficiently high; many Italian coffee makers prefer using a pressure of 9 bar. The amount that the coffee is ground and the amount of force with which it is squeezed in the sieve are the two most important things that determine the pressure.

Espresso machines can’t replicate this crema

Experience and a commitment to excellence in each of these areas define the work of a skilled barista who makes espresso. His espresso also had to pass the sugar test, which requires the crema to be sturdy enough to withstand the weight of a teaspoonful of granulated sugar for a few seconds before the sugar begins to gradually dissolve. The hole in the foam layer must then close again as quickly as possible.

This requires a certain level of skill since the majority of contemporary espresso machines that work with pods or capsules are unable to produce this crema. They often come outfitted with supplementary valves that are designed to foam the coffee just for the added effect. On the other hand, this foam with big bubbles has nothing to do with a real espresso crema. 

By Bertie Atkinson

Bertie Atkinson is a history writer at Malevus. He writes about diverse subjects in history, from ancient civilizations to world wars. In his free time, he enjoys reading, watching Netflix, and playing chess.