A multifunctional sealing device comprising a valve for a drinking receptacle, in which the valve is connected to a discharge conduit structured for connection to the drinking receptacle, wherein the drinking receptacle is located upstream of the valve, wherein a discharge direction of the drinking receptacle is in a downstream direction, opposite to the upstream direction, the valve comprising: - a moveable manoeuvre body for activation of the valve, and - a sealing body connected to the manoeuvre body for opening and closing of the discharge conduit, in which the valve is structured for opening of the discharge conduit by virtue of upstream-directed movement of the sealing body relative to the discharge direction of the valve, wherein the sealing body is of a radially flexible arrangement, wherein the discharge conduit is provided with: (i) a storage seal seat (18, 20) for sealing reception of the sealing body when the valve is in a storage mode; (ii) a utility seal seat for sealing reception of the sealing body when the valve is in a closed utility mode, and (iii) an internal ring-shaped seal portion (30, 30',30") located in a longitudinal region between the storage seal seat and the utility seal seat; wherein the utility seal seat is located upstream of the storage seal seat (18, 20); and wherein both the storage seal seat (18, 20) and the utility seal seat are structured for sealing against the sealing body during closing of the valve, and wherein at least a section of the seal portion (30, 30', 30") is structured for slide-sealing against the seal collar, wherein the discharge conduit is defined by a non-moveable and tubular body, whilst the manoeuvre body comprises an axially movable valve stem located in the tubular body; - wherein the tubular body, along the inner periphery thereof, is provided with a ring-shaped seal bulb extending into the body and including the upstream-directed storage seal seat; - wherein the tubular body, in a region upstream of the seal bulb, also is provided with the utility seal seat in the form of an upstream-directed, ring-shaped end seat; - wherein the valve stem is provided with a flexible and ring-shaped seal collar extending outwardly towards the tubular body and being located in a region upstream of the seal bulb, which allows for sealing both against said storage seal seat and also said utility seal seat; and - wherein the seal collar is structured in a manner allowing it to appear in a radially expanded position for sealing against said end seat when the valve is in the closed utility mode. - a moveable manoeuvre body for activation of the valve, and - a sealing body connected to the manoeuvre body for opening and closing of the discharge conduit, in which the valve is structured for opening of the discharge conduit by virtue of upstream-directed movement of the sealing body relative to the discharge direction of the valve, wherein the sealing body is of a radially flexible arrangement, wherein the discharge conduit is provided with: (i) a storage seal seat (18, 20) for sealing reception of the sealing body when the valve is in a storage mode; (ii) a utility seal seat for sealing reception of the sealing body when the valve is in a closed utility mode, and (iii) an internal ring-shaped seal portion (30, 30',30") located in a longitudinal region between the storage seal seat and the utility seal seat; wherein the utility seal seat is located upstream of the storage seal seat (18, 20); and wherein both the storage seal seat (18, 20) and the utility seal seat are structured for sealing against the sealing body during closing of the valve, and wherein at least a section of the seal portion (30, 30', 30") is structured for slide-sealing against the seal collar, wherein the discharge conduit is defined by a non-moveable and tubular body, whilst the manoeuvre body comprises an axially movable valve stem located in the tubular body; (i) a storage seal seat (18, 20) for sealing reception of the sealing body when the valve is in a storage mode; (ii) a utility seal seat for sealing reception of the sealing body when the valve is in a closed utility mode, and (iii) an internal ring-shaped seal portion (30, 30',30") located in a longitudinal region between the storage seal seat and the utility seal seat; wherein the utility seal seat is located upstream of the storage seal seat (18, 20); and wherein both the storage seal seat (18, 20) and the utility seal seat are structured for sealing against the sealing body during closing of the valve, and wherein at least a section of the seal portion (30, 30', 30") is structured for slide-sealing against the seal collar, wherein the discharge conduit is defined by a non-moveable and tubular body, whilst the manoeuvre body comprises an axially movable valve stem located in the tubular body; - wherein the tubular body, along the inner periphery thereof, is provided with a ring-shaped seal bulb extending into the body and including the upstream-directed storage seal seat; - wherein the tubular body, in a region upstream of the seal bulb, also is provided with the utility seal seat in the form of an upstream-directed, ring-shaped end seat; - wherein the valve stem is provided with a flexible and ring-shaped seal collar extending outwardly towards the tubular body and being located in a region upstream of the seal bulb, which allows for sealing both against said storage seal seat and also said utility seal seat; and - wherein the seal collar is structured in a manner allowing it to appear in a radially expanded position for sealing against said end seat when the valve is in the closed utility mode.