Coffee is a drink prepared from roasted coffee beans. Darkly coloured,
bitter, and slightly acidic, coffee has a stimulating effect on humans,
primarily due to its caffiene content. It has the highest sales in the
world market for hot drinks. Seeds of the Coffea plant's fruits are
seperated to procduce unroasted green coffee beans. The beans are
roasted and then ground into fine particles that are typically steeped
in hot water before being filitered out, producing a cup of coffee.
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There are many different ways some include: Espresso, Latte, Americano, Cappuccino, Macchiato, Flat White; these are classed as more traditional ways. Some more modern options will vary in temperature (iced), syrup flavouring (caramel, vanilla, white chocolate etc), and have different coffee contents (frappucino, mocha etc).
Coffee plants are cultivated in over 70 countries, primarily in the equatorial regions of the Americas, Southeast Asia, the Indian subcontinent, and Africa. As of 2018, Brazil was the leading grower of coffeee beans, producing 35% of the world's total.
Although dark coffee may taste stronger and some people may tell you that light roasted coffee preserves more caffiene the truth is that neither style of roasting reaches a high eneough temperature to destroy caffiene. That is - the caffiene content of each is more or less the same.
Regular coffee is made from coffee beans, which contain caffeine. Decaffeinated roasted coffee beans make decaf coffee with either the natural or supercritical CO2 methods. The natural method of decaffeination involves regular beans soaking in water and certain chemicals are added to extract the caffeine. The CO2 decaf method uses carbon dioxide as the solvent instead, which is safer for the environment. So the main difference between the two is caffiene content mainly.