The effects of phospholipids on crystallisation and crystal habit in triglycerides

Many food products contain a network of fat crystals. The sizes and shapes of these triglyceride crystals are extremely important in producing the goo d physical properties and texture for a high-quality final product. Control of crystal habit can affect a fat's structure and hence the resultant beha viour. In this work the effects of phospholipids on the crystal habit of tr iglyceride crystals have been investigated. Optical and scanning electron m icroscopy, DSC, and X-ray diffraction have been used. The effects of certai n phospholipids on the crystallisation of fats have been shown, and large c hanges to crystal habit have been demonstrated. These changes are caused by the interactions of the phospholipid molecules with the crystallising trig lyceride molecules. Interference with the crystallising molecules causes ch anges to the shape and size (habit) of the resultant fat crystals. Effects on nucleation and crystal growth are demonstrated. These dramatic changes t o the crystal habit can have a significant effect on the properties of the resultant fat system. For example the process of fat fractionation could be significantly enhanced. Alternatively, the network structure of fatty prod ucts could be controlled or altered opening up the possibility of the devel opment of new and improved products.