Kinetic Phase Behavior of Binary Mixtures of Tri-Saturated Triacylglycerols Containing Lauric Acid

Abstract

Describing fat phase behavior is of significant interest for food and non-food applications. One recognized approach to understand the behavior of complex fatty systems is to simplify the fat matrix and to emphasize only the main triacylglycerol (TAG) components. In this context, the kinetic phase behavior and phase transformation paths of binary mixtures of selected saturated monoacids (trilaurin (LaLaLa), trimyristin (MMM), and tripalmitin (PPP)) and of mixed saturated triacylglycerols containing lauric (La) and myristic (M) acids (MMLa and LaLaM) typical from lauric fats were investigated. Kinetic phase diagrams were constructed based on DSC heating thermograms (fast cooling and reheating at 5 °C min−1) and powder X-ray diffraction data. The investigated binary kinetic phase diagram presented an apparently typical eutectic behavior, with a eutectic point that varies depending on the blend composition. Introducing mixed saturated TAGs (MMLa or LaLaM) in binary blends led to a shift in the position of the eutectic point. Considering the binary blends made of LaLaLa, it was shifted from XLaLaLa = 0.7 in the LaLaLa–MMM system to XLaLaLa = 0.5 for the LaLaLa–MMLa mixture, and to XLaLaLa = 0.25 for the LaLaLa–LaLaM blend. Finally, the blend made of the two mixed TAGs (MMLa–LaLaM) also presented a complex non-ideal behavior.