The invention concerns a beverage preparation machine (1) comprising a fluid system comprising a fluid source (2), a pump (3), a heating element (4), at least two container holders (7a, 7b) adapted for receiving ingredient containers (11, 17), a control unit (8) for controlling the fluid system to prepare a beverage by mixing fluid with the beverage ingredient contained in the containers to produce a mixed beverage component in each of the containers, wherein the control unit is further arranged to dispense part or whole of the mixed components sequentially or simultaneously to produce the beverage, wherein the container holders (7a, 7b) differ from one another for holding containers of different sizes and/or types and, and wherein it further comprises separate fluid injection interfaces (9a, 9b) having different structural and kinematic configurations, and arranged for independently delivering fluid in one of the corresponding ingredient containers; each interface being connected to the fluid system and being adapted to a different container.