Lipid crystals play important roles in revealing functionality of melting and rheological behavior and texture formation of lipid-containing colloidal food products, such as gels, cream and emulsions. Recent research on lipid crystals has been increasingly active, mainly because of critical significance of the research for trans-fat alternative and saturated-fat-reducing technology. This review discusses fundamental aspects of structures and properties of lipid crystals from a molecular level to macroscopic network level in close relation to actual production of lipid-containing foods. In particular, recent research of polymorphism of lipid crystals, mixing behavior and crystallization processes has been reviewed.

The fat crystallization on the emulsion is recognized important subject in food, cosmetic, pharmaceutical, ink and any other industrial production. In this paper expressed fundamental and commercial point of the relationship between fat crystals and physical properties of emulsion from the perspective of interaction of emulsifiers and fat crystals.

In the fundamental part expressed as follows, (I) fat crystallization mechanism in the emulsion droplets, (II) fat crystals and emulsion stability, (III) the recent research reports on the relationship between the fat crystals and the physical properties of emulsion. In the commercial part represented about the latest research reports and applications on the food production especially cream production that is leading product in the food emulsion. Furthermore, we discussed with the emulsion stability and the addition effect of sucrose fatty acid ester and decaglycerine fatty acid ester on whipping performance in terms of fat crystals in regard to coffee cream and whipped cream.