ABSTRACT
This chapter discusses the nomenclature, classification, and structure of food phosphates. Most food scientists find the nomenclature and classification of the phosphates, particularly the polyphosphates, extremely confusing. The final form of calcium orthophosphate commonly used in foods is a crystalline precipitate, commonly called tricalcium phosphate. Orthophosphoric acid, or more commonly called phosphoric acid, is a well-known acidifying agent in foods as well as a natural constituent of many fruits and their juices. The common form of dicalcium phosphate used in foods is the dihydrate, dicalcium phosphate dihydrate. Ferric orthophosphate is the commercial name for an iron salt of orthophosphoric acid commonly used as an iron enrichment compound. The pyrophosphates, also called diphosphates in some of the European literature, are the simplest of the condensed or polymeric phosphates. Sodium tripolyphosphate is about 20% as soluble as its potassium counterpart, and it can produce astringent flavors at high levels; fortunately, high levels are usually unnecessary in food applications.
