Xu Yayuan, Zhao Xiaoqing, Wang Qiang, Peng Zhen, Dong Cao
School of Food Science and Technology, Jiangnan University, Oil and Plant Protein Center, Wuxi, Jiangsu Province, PR China.
Wuxi COFCO Engineering & Technology Co., Ltd, Wuxi, Jiangsu Province, PR China.
Food Chem. 2016 Jul 1;202:364-72. doi: 10.1016/j.foodchem.2016.01.102. Epub 2016 Jan 29.
To elucidate the possible interaction mechanisms between DAG-enriched oils, this study investigated how mixtures of DAG-enriched palm-based oils influenced the phase behavior, thermal properties, crystallization behaviors and the microstructure in binary fat blends. DAG-enriched palm oil (PO-DAGE) was blended with DAG-enriched palm olein (POL-DAGE) in various percentages (0%, 10%, 30%, 50%, 70%, 90%, 100%). Based on the observation of iso-solid diagram and phase diagram, the binary mixture of PO-DAGE/POL-DAGE showed a better compatibility in comparison with their corresponding original blends. DSC thermal profiles exhibited that the melting and crystallization properties of PO-DAGE/POL-DAGE were distinctively different from corresponding original blends. Crystallization kinetics revealed that PO-DAGE/POL-DAGE blends displayed a rather high crystallization rate and exhibited no spherulitic crystal growth. From the results of polarized light micrographs, PO-DAGE/POL-DAGE blends showed more dense structure with very small needle-like crystals than PO/POL. X-ray diffraction evaluation revealed when POL-DAGE was added in high contents to PO-DAGE, above 30%, β-polymorph dominated, and the mount of β' forms crystals was decreasing.
为了阐明富含甘油二酯（DAG）的油脂之间可能的相互作用机制，本研究调查了富含DAG的棕榈基油脂混合物如何影响二元脂肪混合物的相行为、热性质、结晶行为和微观结构。将富含DAG的棕榈油（PO-DAGE）与富含DAG的棕榈油精（POL-DAGE）按不同比例（0%、10%、30%、50%、70%、90%、100%）混合。基于等温线图和相图的观察，PO-DAGE/POL-DAGE二元混合物与其相应的原始混合物相比显示出更好的相容性。差示扫描量热法（DSC）热谱表明，PO-DAGE/POL-DAGE的熔化和结晶性能与相应的原始混合物明显不同。结晶动力学表明，PO-DAGE/POL-DAGE混合物表现出相当高的结晶速率，且没有球晶生长。从偏光显微镜照片的结果来看，PO-DAGE/POL-DAGE混合物比PO/POL显示出更致密的结构，有非常小的针状晶体。X射线衍射评估表明，当向PO-DAGE中高含量添加POL-DAGE（高于30%）时，β-晶型占主导，β'晶型的晶体数量减少。
