A comparative study on microstructure, texture, rheology, and crystallization kinetics of palm-based diacylglycerol oils and corresponding palm-based oils

• Published in: European journal of lipid science and technology Vol. 118; no. 8; pp. 1179 - 1192
• Main Authors: Xu, Yayuan, Wei, Changqing, Zhao, Xiaoqing, Lu, Chen, Dong, Cao
• Format: Journal Article
• Language: English
• Published: Weinheim Blackwell Publishing Ltd 01-08-2016; Wiley Subscription Services, Inc
• Subjects: Crystallization; Crystallization kinetics; Diacylglycerol; Hardness; Microstructure; Palm based oils; Rheology
• ISSN: 1438-7697; 1438-9312
• DOI: 10.1002/ejlt.201500369

Palm based diacylglycerol (P‐DAG) oils not only have health‐enhancing properties but also have distinct physicochemical characteristics. However, comprehensive information on the microstructure, rheology, and crystallization properties of P‐DAG oils have yet to be conducted. Thus, P‐DAG oils produced from palm stearin (PS), palm mid fraction (PMF), palm oil (PO), and palm olein (POL) were compared with corresponding palm based oils (P‐oils) in terms of SFC, crystallization properties, rheology, hardness, and microstructure. On the basis of Avrami constant (k) and exponent (n), P‐DAG oils showed higher nucleation and crystallization rate than P‐oils and displayed no spherulitic crystal growth at all examined supercoolings. The complex modulus and phase angle indicated P‐DAG oils except palm stearin DAG (PS‐DAG) appeared to show more strengthening network structure and more solid‐like nature compared to corresponding P‐oils. Substantial changes in crystals size and shape were detected in morphological images of P‐DAG oils excluding PS‐DAG compared to corresponding P‐oils. Nevertheless, all P‐DAG oils showed extremely similar microstructural images with compact structures of very small needle‐like crystals.
Practical applications: This study provides valuable information about the microstructure, texture, rheology as well as the crystallization kinetics of palm‐based diacylglycerol oils. These informative data will contribute to exploitation and application of P‐DAG oils in plastic fat products in the future, which exhibited not only nutritional properties to treat obesity but also distinct physicochemical characteristics.
Palm based diacylglycerol (P‐DAG) oils were produced from palm stearin, palm mid fraction, palm oil, and palm olein. A comprehensive information on solid fat content, crystallization properties, rheology, hardness, and microstructure of P‐DAG oils were conducted in comparison with corresponding palm based oils (P‐oils). Summarily, substantial differences in these properties of P‐DAG oils were detected compared to corresponding P‐oils.
Palm based diacylglycerol (P‐DAG) oils were produced from palm stearin, palm mid fraction, palm oil, and palm olein. A comprehensive information on solid fat content, crystallization properties, rheology, hardness, and microstructure of P‐DAG oils were conducted in comparison with corresponding palm based oils (P‐oils). Summarily, substantial differences in these properties of P‐DAG oils were detected compared to corresponding P‐oils.