Benzoic acid and salts: These are mainly used to protect foods against yeasts and moulds. They are not very effective against bacteria and have to be used in combination with sulphur dioxide in foods prone to spoilage by bacteria. Benzoic acid is used in squashes, hit syrups, cordials, juices, jams, marmalades, preserves, sweetened ready-to-serve beverages, pickles, chutneys, sauces, tomato puree and paste and fat spread. Its effectiveness increases with the lowering of pH and is most effective below of pH 4.5.