What can Crema tell us? what can't tell us?

Crema can tell us:

1. Whether the coffee is fresh or not: a large number of Robosta beans allow us to see a lot of foam, so we can't judge the freshness of coffee by watching the speed at which the foam disappears. Fresh coffee will appear to be very crema throughout the production process (that is, when the coffee comes out, it looks like Coke spurting out), and only when a large amount of water appears, it will stop, thus dividing into two very obvious stages. Old coffee will often see a thin, separate foam in the process of ejection. The resulting coffee is often thin and watery, which means less crema and disappears faster.

2. The degree of coffee quenching: the deeper the Crema, the more dissolved matter enters the cup.

3. Uniformity of coffee quenching: the more stable the Crema, the better and stronger the coffee we make, which means that there are fewer gaps in the coffee powder and fewer mistakes in the production process.

What Crema can't tell us:

1. Whether the coffee is good or not: as long as it is fresh enough, no matter how bad the beans are, no matter how bad the roast can produce rich crema.

2. The oil in coffee is properly emulsified: for a long time, many people, including I thought, Crema told us the degree of quenching of oil in coffee, but the theory tells us that more oil, less foam. If you try making espresso with 5-6bar pressure, you will find that you can still make a lot of crema, but the coffee tastes very insipid because of lack of oil and aroma.

Crema, it's not complicated at all.

The production of Espresso and crema is often complicated, far more than is actually needed. Crema is a very simple part of the whole espresso production process.

Espresso has three main elements, one is water, the second is oily, and the third is foam. While the espresso body is gelatinous (the legendary soy sauce paste), the oil in the coffee is emulsified by hot water at high temperature and high pressure to form a colloid, which is extremely stable. The foam on the surface of espresso disappears very quickly compared to the colloid.

After eliminating the mysterious aura shrouded in Crema, Crema is still a great pleasure of espresso. Its honeycomb structure stores a lot of aromatic substances, releases a large amount of fragrance when the structure disintegrates, and brings enjoyment to our vision and smell at the same time.