Study of oleogel based on sunflower and rosemary components as frying oil

The purpose of study is to research the oxidation resistance and functional properties of oleogels, based on high oleic sunflower oil (HOSFO) and sunflower wax (SFW) with the addition of rosemary extract (RE), sunflower lecithin (SFL) and defoamer polydimethylsiloxane (PDMS), when used as a frying medium for French-fries. HOSFO was structured into an oleogel with SFW. The studies were carried out to determine the possibility of replacing the synthetic antioxidant tert-butylhydroquinone (TBHQ) at a dosage of 200 mg/kg by a natural antioxidant, based on RE and SL in an oleogel.
In the course of this study the following indications of frying fat such as acid value, total polar materials, thermal oxidation degree, induction period, dynamic viscosity, fatty acid content and organoleptic were determined. It was found out that the introduction of SFW increased the induction period of HOSFO by 1.6 times, and the additional introduction of PDMS and antioxidants increased this figure by 2 times.
The rate of accumulation of oxidation products in oil decreased when SFW and antioxidants were added. The thermal oxidation degree increased most quickly in oil without additives, while in oleogels it decreased significantly. The introduction of SFW into oil contributed to a noticeable decrease in the absorption of oil by potatoes. Fried potatoes in oleogel absorbed 34-39 % less oil than the potatoes that were fried in HOSFO.
The addition of 0,07% of complex antioxidant (RE+SFL) to the oleogel increased the operating time of frying oil by at least 2 times, approximately the same as that of the oleogel with TBHQ. This makes it possible to replace the synthetic antioxidants in oleogel with natural RE and SFL. The newly developed oleogel is a frying oil that has a longer service life and allows to get fried products with less fat.