caffeine
There is a particularly strong bitterness, stimulating the central nervous system, heart and respiratory system. Appropriate amount of caffeine can also reduce muscle fatigue, promote digestive juice secretion. Because it will promote kidney function, a diuretic effect, to help the body will be extra sodium excreted. But excessive intake can lead to caffeine poisoning.

Tannic acid
After boiling the tannic acid will break down into coke, so brewing too long the taste of coffee will be worse.

fat
One of the most important is acidic fat and volatile fat.

Acid fat
That is, fat contains acid, its strength varies due to different types of coffee.

Volatile fat
Is the main source of coffee aroma, it is a kind of material will emit about forty kinds of aromatic.

protein
The main source of calories, the proportion is not high. Coffee at the end of the protein in the coffee, most will not dissolve out, so the intake is limited.

sugar
Coffee beans contain about 8% of sugar, after baking most of the sugar will be converted into caramel, so that the formation of brown coffee, and tannic acid combine to produce sweetness.

fiber
Raw beans after the baking of carbon fiber, and caramel will be combined with each other to form the color of coffee.

Mineral
Contains a small amount of lime, iron, phosphorus, sodium carbonate and so on.