Characterization of the Physicochemical Properties of Sunflower Oil Oleogel

Monoacylglycerols can be used as organogelator in production of oleogels. In this study, the effect of monoacylglycerols addition on the physicochemical properties of sunflower oil was evaluated. Three oleogel samples were made by adding 0.5, 3.0 or 5.0% distillated monoacylglycerols into the sunflower oil. Fatty acid composition, iodine value, oxidative stability, melting point, solid fat content, crystallization kinetics and rheological properties of the samples were evaluated. Changes in the samples’ peroxide value and free fatty acid content during storage at 60 °C were also investigated in a 31-day time course (with 3-day intervals). Compared to the pure sunflower oil, the oleogel samples made using monoacylglycerols had higher saturated fatty acid content, melting point, solid fat content, storage and loss modules, and lower iodine value and induction period of crystallization. Though monoacylglycerols had not any effect on the induction period of oxidation, the oleogels containing 5‌% monoacylglycerols had higher peroxide value and free fatty acid content after 14 days of storage at 60°C. Totally, by the addition of monoacylglycerols into the sunflower oil, its properties shifted from oil to a fat. This was accompanied with a little increase in saturated fatty acid content and a decrease in oxidative stability.