The functional properties of different lipids in foods are demonstrated and related to the structure of lipid or lipid-water phases. On the basis of new X-ray data on the crystal structure of the B'-form and the a + B' transition in fats, the polymorphic transitions are considered as different lateral arrangements of triglyceride dimers. The physical properties of fat crystals can be explained from the structures, as well as possibilities to influence the polymorphic transitions.
Molecular interaction between polar lipids and proteins or starch is discussed, and the effect of the amylose-lipid inclusion complex on gelatinization temperature and water penetration of starch is demonstrated.
Aqueous phases of polar lipids can form different structures, and the lamellar liquid-crystalline phase is the most important one with regard to functionality in foods. The role of this phase in emulsification and in foam stabilization is considered. The effect of lipids in the bread making process can be fully explain ed on the basis of foam stabilization by lipid monolayers provided by a dispersed lipid-water phase. A cubic phase, which can solubilize large amounts of proteins, is finally described.
"Some Effects of Lipids on the Structure of Foods,"
Food Structure: Vol. 1
, Article 6.
Available at: http://digitalcommons.usu.edu/foodmicrostructure/vol1/iss1/6