Question : Its an in lasting phenomenon to see how this bland green bean turns to a flavorful coffee beary Coffee bean is a seed and like any other seed is rich in proteins, fats and all necessary ingredients for giving birth to a new plant. When exposed to heat, the fats and carbohydrates in the bean turn into essential oils, which give the characteristic taste and aroma to the coffee bean, The degree of roasting depends on the need or purpose of use