In this master's thesis oleogels were prepared from sunflower, olive, safflower, linseed and rapeseed oil. In order to find out how oil unsaturation degree affects the oleogels texture properties, fatty acid composition and iodine value of oils were determined. Texture properties measured included firmness and stickiness. Oleogels were made from fresh and highly oxidized oils as well as from oils with added rosemary extract. Beeswax was used as oleogelator at 1.5%, 2%, 3%, 5% and 7% (w/w). Oleogels were subjected to three different cooling processes and to different storage conditions in order to determine how oleogelator amount, the cooling and storage temperature affect the oleogels texture properties and oil binding capacity (OBC). We found out that the texture properties and OBC of oleogels are influenced by the beeswax content, the cooling and storage temperature, and oil type. The investigated oleogels are thermoreversible. The degree of lipid peroxidation in oils and oleogels was monitored by the peroxide value. The antioxidant potential of rosemary extract in oil and in oleogel was determined. The addition of the antioxidant, despite the fact that it prevents oxidation of oil in the oleogel, weakens the 3D structure of oleogel and so affects the texture properties. We also found out that the solid structure of oleogels slows down lipid peroxidation in the oleogel and preserves the antioxidant potential of rosemary extract.
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