Abstract: The invention relates to an apparatus for introducing an additive material (131) in the form of a liquid or granulated solid into a liquid (40) stored in a first container (150). The additive component (131) is stored separately from the liquid (40) in a dip tube or conduit (130). The dip tube (130) is a resilient hollow tubular member and has a valve (300) at one end, adapted to open when the dip tube (130) is subject to internal pressure to allow the passage of said additive material (131) therethrough. The valve prevents the additive material (131) from leaking or dripping into the liquid (40) in the first container (150) when the dip tube and first container are at the same pressure, but which allows the passage of liquid or pourable solid additive from the dip tube (130) into the liquid (40) in the first container (150) when the dip tube is pressurised by introduction of propellant fluid (116, 516).