Roasting gives the beans their flavor and keeps them fresh for longer. To roast beans for instant coffee, beans are dropped into a pre-heated, rotating drum. The intensity of the flavor will depend on the duration of the roasting process - the longer the beans are roasted, the “darker” the coffee (and the less caffeine they contain). https://disqus.com/by/disqus_FC4z7JLiqo/about/