X-ray diffraction and differential scanning calorimetry studies of β′ → β transitions in fat mixtures

The polymorphism of five new fat mixtures was studied by differential scanning calorimetry and X-ray diffraction. The melting curves of blends were analysed by DSC and pulsed NMR. The short spacing determinations indicate that the β′ → β transition was faster for mixtures II and V than for mixtures I, III and IV. The fatty acid composition was an important factor which influences polymorphic stability of the examined blends. The slightly higher content of palmitic acid in mixtures II and V had no impact on the rate of β′ → β transitions under the experimental conditions. The trans fatty acids and stearic acid increased the stability of the β′–form and therefore mixtures I, III and IV appeared to be smooth and creamy.