Investigation of the Thermal and Structural behavior of Two Lauric Fats in Bulk and Water-in-oil Emulsion States
Raul Flaviu Petruta, Prudent Placide Anihouvia, Christophe Bleckera, Anne Dombreeb, Vera Van Hoedb, Sabine Danthinea
aUniversité de Liège, Gembloux, Belgique
bPuratos Group, Industrialaan 25, Zone Maalbeek, 1702 Groot-Bijgaarden, Belgique

In a previous study the thermal and polymorphic behavior of four different industrial lauric fats which are sold under the same commercial description, was compared (1). According to the findings the four fats were split in two groups based on the similarities found at polymorphic level. In the present paper two of these industrial lauric fats (F1 and F2, one from each group) were incorporated into oil-in-water emulsions. The objective of this study was to point out the differences in the crystallization and polymorphic behavior between bulk and emulsified fat. For that purpose, the two fats were investigated for their thermal and polymorphic behavior by differential scanning calorimetry (DSC) and X-ray diffraction (XRD), both in bulk and emulsified state. In the bulk phase at 4oC, the X-Ray measurements revealed β’1 form for F2 fat and β’2 for F1 fat, both of them in a double chain lamellar structure (2L). In the emulsified state the polymorphic form of the crystals was different, α forms being observed besides β’1 and β’2, respectively. The longitudinal organization was also 2L. Upon heating, no β’ – β transition was observed before complete fat melting, neither for bulk or emulsified state. Finally the DSC and X-Ray investigations of the two fats, made possible the observation of the differences in the crystallization behavior and kinetics that occurred for fats in the bulk and emulsified state.

1.	1.	Anihouvi, P.P., C. Blecker, A. Dombree, S. Danthine, Comparative Study of Thermal and Structural Behavior of Four Industrial Lauric Fats, Food Bioprocess Technol. 6:3381–3391 (2013)