The present invention concerns an adapter (1) which is suitable to be mounted on and to cooperate with the neck (7) of a container (3) in order to allow a product contained in the adapter (1) to flow out into the interior of said container (3), said adaptor including: at least one tank (4) which is suitable to contain said product, said tank (4) having a first opening (2) which is suitable to transfer said product from the tank (4) into the interior of the container (3), a single-use or reversible movable means for sealingly closing (5) the first opening (2), a means for activating (25) the movable means for sealingly closing (5) so as to allow said movable means for sealingly closing (5) to open and said product contained in the tank to flow out into the interior of the container (3).
The present invention also relates to a container comprising said adapter and to a method for preparing and/or serving a liquid.

Provided is an accommodating device for different materials, which includes a fixed part fixed around a container neck and an operating part disposed around the fixed part and coupled thereto. An accommodating part having a storage space extends downward within the operating part, and a lower end part and an outer ring-shaped part of the accommodating part are sealed by a sealing support part and a sealing part of the fixed part disposed around the container neck and coupled thereto. In the accommodating part, a tab for breaking perforations, which is formed on a lower end of the accommodating part of the operating part, breaks the perforations formed between the sealing support part and the sealing part when a consumer rotates the operating part. During this process, a protrusion part protruding from the upper side of the sealing part is pushed downward by a side protrusion piece of the operating part so that the different type of material stored in the storage space of the accommodating device falls into the container and undergoes a mixing process. The sealing support part disposed around the outer ring-shaped part of the accommodating part and coupled thereto and the sealing part formed inside the sealing support part are configured such that an inner ring-shaped part of the sealing part tightly contacts an inner wall part of the lower end of the accommodating part so as to maintain sealing force thereof.

A capsule cap for a beverage container of the present invention includes: a cylindrical lower coupling unit (10) keeping an additive (A) therein; a cutting unit (20) having a cylindrical cutting body (21) inserted in a lower body (11) and vertically moving down to cut a seal (12) so that the additive (A) drops; and an upper coupling unit (30) disposed over the lower coupling unit (30) to be turned and vertically move the cutting unit (20), in which drinking water contained in the beverage container an additive are separately kept, so the drinking water and the additive are prevented from spoiling. Further, spiral guides are formed, so torque is easily changed into straight force, thereby achieving easy cutting and opening.