Why is coffee bitter? How to make coffee less bitter?

Coffee is best known for its bitterness, but caffeine actually accounts for at most 10 percent. This can be seen from the fact that roasted beans contain caffeine concentrations that are not affected by roasting, and decaffeinated coffee also has bitter tastes.

So where does the remaining 90% of bitterness come from?

One of the sources of coffee bitterness is brown pigment.

Brown pigments can be classified according to molecular size, and the larger the molecule, the more bitter it is. In the case of coffee, deep roasting increases brown pigment, followed by larger (more bitter) pigments. When you cook deep-baked beans in daily life, you will find that the bitterness is stronger and the taste is stronger.

In fact, Arabica and Robusta species differ in bitterness intensity and taste. This is also due to the amount of brown pigment and molecular size caused by different. Robusta species have lower oligosaccharide content than Arabica species, do not caramelize, and easily produce larger molecular pigments, so even if lightly baked, they often taste bitter.

Another source of bitterness is the cyclization of seven diamino acids produced when amino acids and proteins are heated. This is a combination of two amino acids. Different combinations will cause different bitterness intensity. In addition to coffee, cocoa, dark beer and other parts of the bitter is also composed of this substance.

So, is it impossible to control the intensity and intensity of bitterness? Of course you can. Bitterness can be changed by changing the type of coffee bean, roasting degree, roasting method and extraction method.