Physicochemical properties of soybean-based diacylglycerol before and after dry fractionation.

In the present work, the physicochemical properties of soybean-based DAG (SDAG), especially the effects of dry fractionation on crystallisation properties, were investigated. The solid portion (SF) and liquid portion (LF) were obtained by dry fractionation of SDAG. The physicochemical properties of soybean oil, SDAG, LF, and SF were investigated, including the determination of acylglycerol composition, fatty acid (FA) composition, slip melting point (SMP), iodine value (IV), solid fat content (SFC), X-ray diffraction (XRD), and differential calorimetry (DSC). The DAG content of SF (44.79 ± 0.87%) was higher than SDAG (41.94 ± 1.28%) and LF (42.22 ± 0.29%). After fractionation, SF contained higher levels (p < 0.05) of saturated fatty acids (SAFA) and lower levels (p < 0.05) of unsaturated fatty acids (UFA) than LF and SDAG, which was in accordance with the differences in IV and SMP. The SFC of SF (0°C, 17.25 ± 0.65%; 20°C, 10.66 ± 0.28%; 40°C, 3.47 ± 0.14%) was significantly higher than those of LF and SDAG (p < 0.05). With respect to the crystal structures, it was demonstrated that SF contained more β' crystals than SDAG and LF and could be better used in shortening. Overall, the present work provides a theoretical basis for the industrial applications of SDAG and its fractions. [ABSTRACT FROM AUTHOR]