Crystallization and Polymorphism Behaviour of Lipid Systems Containing Triacylglycerols with Added Diacylglycerols
Silva, R C1, Grimaldi, R. 2, Soares, F.A.S.M1, Gioielli, L A1
1 Department of Biochemical and Pharmaceutical Technology, Faculty of
pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes n. 580, B16,
CEP 05508-900, São Paulo, SP, Brasil
2 Department of Food Technology, FEA,Unicamp

Recent scientific studies show that minor lipids (ML) affect crystallization and can promote or inhibit it, by the addition or removal of these compounds. However, few studies have considered the effect of addition of monoacylglycerols (MAGS) and diacylglycerols (DAGs) on pure triacylglycerols (TAGs). The study of polymorphism and crystallization behavior of a pure lipid system has great scientific importance as a means of achieving possible understanding of the involved phenomena, which will provide basic knowledge for directing the addition or removal of these compounds in different raw materials. Thus, this research aims to study the effects of incorporation of ML (MAGs and DAGs) on different pure TAGs in crystallization and polymorphism. Pure TAGs (SSS, PPP and OOO) and pure DAGs (SS, PP and OO) were used. The morphology of fat crystals was analysed by polarized light microscopy and the crystallization was evaluated by differential scanning calorimetry. The addition of 5% DAGs changed the melting and crystallization behavior of the three TAGs studied. Saturated DAGs tended to co-crystallize with saturated TAGs, retarding the transition. The addition OO promoted polymorphic transition in all pure TAGs, probably because tilted unsaturated fatty acids resulted in greater TAGs mobility, decreasing the interactions between DAGs and TAGs.