Black coffee is coffee without any modification. It combines the five characteristics of coffee, sweet, sweet, sour and bitter. It is primitive, rough, profound and intriguing. Black coffee emphasizes the aroma of coffee itself. Bitterness is the basic taste of black coffee, and its strength and texture are different. Raw beans only contain a very small amount of bitter ingredients, and then the most symbolic bitter taste of coffee is produced by carbonization caused by sugar, partial starch, fibrous caramelization and baking. Black coffee also has a sour taste. Proper heating can produce moderate acidity, which can make coffee taste better and make people feel deeper. The sweetness of black coffee is closely related to the bitterness, so refreshing and excellent black coffee must have sweetness.

However, plain coffee doesn't help. ...