Phase behavior of binary mixtures of tripalmitin, triolein, and trilinolein

Abstract

The phase behaviors of tripalmitin (PPP), triolein (OOO), and trilinolein (LLL) mixtures were investigated using differential scanning calorimetry (DSC). Samples were cooled from 85 to ?80 ? for the PPP/OOO and PPP/LLL systems and from 50 to ?100 ? for the OOO/LLL system and heated to the initial temperature. With respect to the PPP/OOO and PPP/LLL mixtures, the crystallization and melting temperatures of PPP decreased with decreasing fraction of PPP while those of OOO and LLL were almost constant at any fraction. It was presumed that pure or nearly pure PPP and OOO crystallized in an unstable form during cooling and transformed into the stable form during heating. In the OOO/LLL mixture, the crystallization and melting temperatures of OOO and LLL depended on their respective fractions. It was suggested that the two components crystallized almost independently in the PPP/OOO and PPP/LLL mixtures and interacted with each other in the OOO/LLL mixture.