A connector structure for a container, the connector structure comprising: a socket said socket being a substantially columnar member having an upper end surface and a lower end surface, whereby the socket is attachable to an opening of the container and has a shape such that the upper end surface and the lower end surface deviate from a mutually parallel state by an inclination angle ( θ), the socket further having a substantially columnar shaped upward-opening recess formed around the axial centre on the upper end surface of the socket and formed along an axis (Cs) that is orthogonal to the upper end surface; a straight siphon tube directly attached to the socket by being inserted into a through-hole which penetrates the socket, said through-hole having a circular shape in cross section and extending along the axis (Cs) from the centre of the bottom surface of the recess to the lower end surface; and a substantially L-shaped plug having a downward-protruding projection, wherein the plug has a gas channel and a liquid channel, wherein the socket has a gas channel, wherein the plug is joined to the socket by inserting and fitting the projection in the upward-opening recess, thereby forming a gas channel for introducing gas into the container and a liquid channel for extracting liquid from the container, the connector structure further comprising a bottle cap for securing the socket to the opening of the container by screwing an internal threaded portion of the bottle cap onto an external thread of the opening, wherein the through-hole of the socket is inclined relative to an axis of the bottle cap so that, in the state where the connector is secured to the opening of the container, the axis (Cs) of the siphon tube and the axis of the bottle cap have a predetermined inclination angle ( θ) therebetween and the through-hole serves as a passage through which the siphon tube extends into the container. a socket said socket being a substantially columnar member having an upper end surface and a lower end surface, whereby the socket is attachable to an opening of the container and has a shape such that the upper end surface and the lower end surface deviate from a mutually parallel state by an inclination angle ( θ), the socket further having a substantially columnar shaped upward-opening recess formed around the axial centre on the upper end surface of the socket and formed along an axis (Cs) that is orthogonal to the upper end surface; a straight siphon tube directly attached to the socket by being inserted into a through-hole which penetrates the socket, said through-hole having a circular shape in cross section and extending along the axis (Cs) from the centre of the bottom surface of the recess to the lower end surface; and a substantially L-shaped plug having a downward-protruding projection, wherein the plug has a gas channel and a liquid channel, wherein the socket has a gas channel, wherein the plug is joined to the socket by inserting and fitting the projection in the upward-opening recess, thereby forming a gas channel for introducing gas into the container and a liquid channel for extracting liquid from the container, the connector structure further comprising a bottle cap for securing the socket to the opening of the container by screwing an internal threaded portion of the bottle cap onto an external thread of the opening, wherein the through-hole of the socket is inclined relative to an axis of the bottle cap so that, in the state where the connector is secured to the opening of the container, the axis (Cs) of the siphon tube and the axis of the bottle cap have a predetermined inclination angle ( θ) therebetween and the through-hole serves as a passage through which the siphon tube extends into the container.