A carbonating apparatus includes an elongated carbonation chamber defining a longitudinal axis and having an inlet end and an outlet end. A manifold assembly is provided at the inlet end of the carbonation chamber. The manifold assembly includes a manifold body having an outlet end connected to the inlet end of the carbonation chamber and an inlet end. A liquid passage and a carbon dioxide passage extend in a direction between the inlet and outlet ends of the manifold body in communication with the inlet end of the carbonation chamber. At least one check valve is disposed inside the liquid passage within the manifold body. At least one check valve is disposed inside the carbon dioxide passage within the manifold body.