Pure coffee beans, after being roasted, will not be greasy and sticky, natural and mild. If additives are used during the roasting process, the doped coffee beans will be greasy, sticky (signs of butter, cooking oil ...), strong smells mixed with butter ...
How to distinguish pure coffee in powder form
Pure coffee powder is very light, smooth, loose and loose. Pure coffee powder has a low density, so it tends to float to the top when added to water, while other cereal grains sink more quickly.
When roasting to the appropriate temperature and time, the coffee powder has a dark brown color (if the roasted coffee beans have not reached the temperature and time of the first explosion, the powder will have a bright yellow color with a sour taste and strong odor).