The most simple answer = it’s a shot of espresso topped with hot water
The story goes that when American soldiers were stationed in Italy during WWII, they balked at the strong flavour of the espresso drunk by the natives.
Raised on drip coffee, the full-bodied and rich flavors of an espresso were unfamiliar.
So, they hit on the idea of adding more water to a shot of espresso, and the famous black drink was born. Simple, right?
By the way, Italians aren’t that keen on drinking coffee in any other way besides espresso (they call diluted espressos ‘dirty water’)
An espresso (meaning ‘quick’) is made by forcing water at high pressure through finely ground coffee. It creates a small amount of richly flavored coffee.
Perhaps the most characteristic element of espresso is the crema.
What Is Crema?
Coffee beans which have been carefully processed will be full of aromatic oils.
When an espresso is brewed, the hot water first forces those oils out of the beans.
You might have noticed a light brown, creamy substance coming out of the espresso machine before the dark coffee.
This substance rises to the top in what some people call, ‘the guinness effect’. For a long time, crema was seen as a mark of a great brew.
Unfortunately, as with most things coffee related, it’s not as simple as that.
If you’ve read our article on coffee bloom, you’ll know that beans also give off Carbon Dioxide for 48+ hours after roasting.
If your espresso has been made with freshly roasted coffee the cream may taste sour due to the favor of CO2.
An Americano is simply an espresso that has been poured over, or been diluted with hot water. The cream rises to the top, giving you a longer coffee drink, with the oily richness preserved.
So a true Americano will have a layer of crema.