What is cream and how is it formed?
The crema is the fascinating result of the high pressure infusion that takes place during the extraction of the espresso. Without pressure, the cream would not exist.
During the process, pressurized water dissolves the carbon dioxide trapped in the roasted coffee beans, when the brewed liquid returns to normal atmospheric pressure on its way to the cup, the latter can no longer hold all the gas, which escapes from solution in the form of countless tiny bubbles, these bubbles get trapped in the coffee and appear as a stable crema.
Interpreting the secrets hidden in the crema of the espresso: what does it reveal?
The crema dell'espresso is an important element bringing with it a wealth of information for both baristas and coffee lovers. Its influence on the perception of coffee is undeniable, but it is important to note that despite its relevance, crema alone is not sufficient to fully predict the nature of a coffee . Here are the precious clues that we can gather from this fascinating feature:
Freshness : The freshness of the coffee has a direct link with the amount of carbon dioxide trapped in the bean. The older the coffee, the lower the presence of carbon dioxide will be and, consequently, the less abundant the crema will be, which can therefore prove to be an indicator of the coffee's freshness.
Degree of toasting : The degree of toasting has a significant influence on the crema. To obtain a darker and denser crema, more intense roasting is required, often preferred by industrial roasters in order to destroy the aromatic profile, hence the purely Italian cultural heritage of the coffee which must hold the sugar for 10 seconds.
Why mix the cream
Crema usually has a more bitter taste than espresso, in fact if we separate it from the coffee, the latter will be sweeter.
We recommend mixing it , the goal is to find balance between acidity, sweetness and bitterness working together in the cup. An excess of one of these elements will cause the espresso to become unbalanced.
Other factors affecting the cream
Other variables are the time, temperature and variety of coffee, these can make the crema coarser or thinner, darker or lighter.
The honey hey natural coffees they usually make more crema since they contain more lipids, proteins, sugars, and minerals. While washed coffees create less crema.
When it comes to variety, i Robusta coffee they create more cream, but this will be less compact and less aromatic than the cream of an Arabica coffee.
During the extraction of the espresso, the temperature and the pressure present may affect the type of cream. If your crema is light, thin and disappears quickly, your espresso may have been under-extracted, less common causes could be: the machine pressure is too low, the coffee is too stale or the water is too cold.
Thanks and Happy Coffee!