Polymorphism in Fats and Oils

Triacylglycerols (TAGs) are the major components of fats and oils and biologically important organic molecules along with proteins and carbohydrates. In industrial applications, TAGs are the main components in cream, margarine, and confectionery fats in foods and as matrix materials in pharmaceuticals and cosmetics. The physical behavior of TAGs influences the physical properties of fat-based products, such as appearance, texture, plasticity, morphology, and rheology. Most fat-based products are multicomponent TAG mixtures, containing different kinds of fatty acid moieties. Their complex physical properties are ascribed to polymorphism of individual TAG components and their mixing behavior. Therefore, research into the physical properties of the fat-based products usually starts with an understanding of individual TAG molecules and subsequently moves on to an understanding of the mixed systems, while combining this microscopic information with the macroscopic properties of texture, crystal morphology, and rheology. The macroscopic properties of fats and oils will be discussed in other chapters of this volume.