Coffee beans contain about 100 different substances, including caffeine, tannic acid, oil and nitrogen compounds. Every100g of instant coffee contains 44 ~100g of caffeine; Every 100g of brewed coffee contains 64 ~ 124mg of caffeine.
Coffee is a stimulant, which will have many effects on human body. It can also stimulate the central nervous system and respiratory system, dilate blood vessels, speed up the heartbeat, enhance the strength of striated muscles and relieve brain and muscle fatigue.
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Coffee is one of the three major beverages in the world. It is made from roasted coffee beans. It is the main drink popular in the world together with cocoa and tea.
Coffee tree is a perennial evergreen shrub or small tree of Rubiaceae. Daily coffee is made from coffee beans with various cookers. Coffee beans refer to nuts in the fruit of coffee trees, which are baked by appropriate methods.
A standard cup of coffee should not be bitter. A qualified barista will strictly carry out every step when making coffee, and finally the coffee presented to the guests will be sweet, sour, mellow or clean in different degrees.
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