Physicochemical properties of palm stearin and rice bran oil blends / Amalyna Kelana

Oil blends were formulated by mixing palm stearin (PS) and rice bran oil (PS) in different ratios of 70:30, 50:50, and 30:70. The solid fat content (SFC), slip melting point (SMP), iodine value (IV), hardness index (HI), triglyceride profiles, major fatty acids, polymorphism and microstructure were evaluated. Results indicated that blending PS with RBO lowered the SFC, SMP and HI of the blends while the IV was increased significantly (p < 0.05). The decrease in palmitic acid and an increase in unsaturated oleic and linoeic acid were observed in all blends. X-ray diffraction analysis revealed that all the blends resulted in mixtures of both β and β΄ polymorphs. Small thin needlelike crystals were identified in the blends which can contribute to the soft and smooth texture of products such as margarine and fat spread. Blend 30:70 PS:RBO was found to be most suitable for food application due to its good spreadability and ability to melt completely at body temperature.