Influence of Monounsaturated\nTriglycerides on the\nCrystallization Pathway of Fully Saturated Triglycerides

The effect of composition on the polymorphic crystallization\nin\nblends of fully saturated and monounsaturated triglycerides was investigated\n(H3 denotes fully saturated, and H2U denotes monounsaturated triglycerides).\nFully hydrogenated rapeseed oil (FHRO) and palm oil stearin (POSt)\nwere used as H3 sources. Palm oil (PO) served as an H2U source. Different\nH3/H2U ratios and cooling rates (1, 5, and 10 °C min<sup>–1</sup>) were investigated. Differential scanning calorimetry, time-resolved\nsmall- and wide-angle X-ray scattering, and oscillatory shear experiments\nwere employed to investigate the melting behavior as well as the nano-\nand microstructural development. The data reveal different kinetic\npathways, even selective cocrystallization, depending on the molecular\nmakeup of the H3 fraction. The POSt-PO blends first crystallize in\nan α phase that transitions into coexisting β′\nand β phases. The FHRO-PO blends showed a longer persisting\nα phase that transitions into β even before a β′\nphase could be identified. This indicated separate crystallization\nof H3 triglycerides. The polymorphic pathways are compared to the\nmelting behavior and microstructural development during crystallization.\nFurther, the question of mixed crystal formation in the H3 fraction\nof the FHRO-PO blends was addressed by studying H3 blend replicates\nin the absence of H2U triglycerides. This paper is the second part\nof a series investigating the interplay of polymorphic transition\nand mixed crystal formation.