The present invention relates to a preservative system capable of protecting against spoilage by bacteria, yeasts and moulds in carbonated and non-carbonated beverages. In accordance with the invention this objective is realized with a preservative system comprising a combination of propionate with vanillin and/or cinnamate. Vanillin and propionate are both known for their anti mould action. However the dosages that are needed of the separate ingredients are too high for most applications. The present inventors found that potassium cinnamate at low concentrations has a positive effect on the inhibition of moulds in combination with vanillin and propionate. Moreover, the present invention, using a combination of vanillin, propionate and cinnamate accomplishes complete inactivation of all moulds at manageable sensory levels. Hence the present invention provides a preservation system comprising combinations of propionate with vanillin and/or cinnamate as well as applications of such preservation systems in alimentary products, especially carbonated and non-carbonated beverages.