I drink people think good is good, feel bad is bad. Coffee, bitter, astringent, acid, regan is the basic attribute, we ordinary people are just from these four aspects to evaluate, when you drink more, you can drink this acid belongs to what fruit acid, such as citric acid (more stimulating), malic acid (micro fruit astringency in acid), citrus acid (soft), Grape acid. . . In fact, these are the results of the combination of taste buds and nasal feelings with our daily memory, including the aroma of coffee. Professional coffee makers will deliberately overlap with memory and taste and smell to evaluate coffee.