Role of the oil on glyceryl monostearate based oleogels

The high consumption of saturated and trans fats, used in the formulation of lipid-based foods, is associated with incidence of health problems. Organogels or oleogels are a novel class of structured lipids formed from liquid oil as continuous phase entrapped within network of structuring molecules. The aim of this study was to understand the role of oils with different composition on the formation of glyceryl monostearate (GM) gel network. Glyceryl monostearate-based oleogels were produced with the minimal concentration of 5 wt% in sunflower (SF), high oleic sunflower oil (HOS) and coconut oil (CO). The influence of the oil type on the physicochemical properties of the gel was analyzed. The GM gels showed a solid-like behavior using either high oleic sunflower or sunflower oils but did not form a true gel with coconut oil. Although different oils could affect the crystal formation, all gels exhibited needle-like crystal morphology regardless solvent quality. The GM crystals arranged in a lamellar configuration are responsible for entrapping both SF and HOS oils. Degree of saturation of oils might affect GM oleogel properties. Long chain monounsaturated fatty acids favored the packing of GM crystals in a cohesive gel. Furthermore polymorphism with preferential crystalline beta' form of GM was formed using a medium containing one and two unsaturation. In conclusion, it was observed that the type of oil influenced the formation of the GM gel network. These findings allow the better understanding of GM-based oleogels, providing opportunity to design for food products with improved technological and nutritional properties. (AU)