Sodium citrate dihydrate is the most widely used emulsifying salt in sliced processed cheese products. It is commonly used as a buffering agent in combination with the citric acid to provide precise pH control required in many food and beverage applications.

The main functions of citric acid and the citrates in foods and beverages can be summarized as follows:

• as a flavor adjunct, to improve taste
• as a pH control agent, e.g., for gelation control, buffering and preservative enhancement
• as a chelating agent to improve the action of antioxidants and prevent spoilage of foods such as seafood

The reaction of citric acid and bicarbonate liberates carbon dioxide, which aids the dissolution of active ingredients and improves palatability. Effervescent systems are widely used in denture-cleaning products, as well as pain relief and vitamin tablets. The major components of cleaning products are surfactants and builders. Other ingredients are added to provide a variety of functions, e.g., increasing cleaning performance for specific soils/surfaces, ensuring product stability, and supplying a unique identity to a product. Citric acid is employed as an industrial cleaner to clear steam blocks and hot water systems of calcium and rust layers. As a chemical polish, citric acid is used to treat aluminum, copper and other metal surfaces. Citric acid and citrates are used as buffering and complexing agents in electroplating baths. The building and textile industries also take advantage of citric acid’s outstanding chelating ability as well as its non-toxicity. Examples include setting retarding of gypsum plasters and textile finishing. 

Further industrial applications of citric acid and citrates range from desulphurization of flue gas and oil recovery to the decontamination of radioactive nuclear reactor materials.