A roasting and grinding system (100) for preparing and delivering on demand roast and ground coffee, the system having: one or more raw containers (10, 10′, 10″, etc.) having green coffee beans of the same or of different types; a roasting unit (20) receiving green coffee beans from one or more of the raw containers (10, 10′, 10″, etc.) at the time, the roasting unit (20) adapting automatically the roasting parameters to the type of green coffee beans to roast; a conservation area (30) where the roasted coffee is stored at appropriate atmosphere until it is grinded; a grinding area (40) having one or more grinding units (41, 41′, 41″, etc.) one per type of coffee to be ground, adapting automatically the grinding parameters to the type of coffee or coffee mix to be ground. The invention further relates to a raw container (10, 10′, 10″, etc.) having green coffee beans detachably connectable to a roasting and grinding system (100), and to a method for roasting and grinding coffee blends on demand using such a system.