Device for closing beverage containers, comprising a basic structure configured for coupling to the beverage container, the basic structure enclosing at least one passage channel for beverage, a closing element coupled releasably to the basic structure for closing the at least one passage channel, at least one axially displaceable holder which is arranged at least partially in the passage channel and which is at least partially filled with an additive to be added to the beverage, wherein an upper side of the holder to be opened facing toward the closing element and an underside of the holder remote from the closing element initially close the holder substantially medium-tightly, and—at least one lower perforation structure; positioned under an underside of the holder remote from the closing element and configured to perforate the underside of the holder during downward displacement of the holder in the passage channel in the direction of the lower perforation structure, whereby the additive can be released to beverage present in the beverage container.