Fat crystallisation is also important in fractionation processes, when products with different melting and physical properties are made (Hartel, 1992; Walstra, 2003).

Section 7.2 of this chapter will deal with crystallisation, polymorphism, and melting. It will discuss nucleation, crystal growth, crystal size, and morphology, polymorphism, solid fat content (SFC), microstructural development, macroscopical and mechanical properties, and melting behaviour. In the section on polymorphism, triglycerides, diglycerides, and monoglycerides are treated separately. The next section of this chapter (7.3) deals with phase behaviour. Phase diagrams of mixtures of triglycerides, real fats, and mixtures of triglycerides with mono-and diglycerides are discussed. Section 7.4 of this chapter deals with lipid/water interaction. After explaining the concept of a liquid crystalline phase, the interaction of water with monoglycerides, phospholipids, triglycerides, diglycerides, and soaps will be discussed.