Reducing the oxidation of cold pressed sunflower oil by adding rosemary or parsley
Katerina Temelkovska, Gorica Pavlovska
Cold-pressed sunflower oil is produced by pressing the highest quality sunflower seeds. They are less stable and easily oxidized. It is important to extend the shelf life of these oils by preventing and slowing down the oxidation process.Subject to this analysis was the “Super Vita” cold pressed sunflower oil, with and without adding rosemary and parsley. The degree of oxidation was determined through the peroxide value (PV), taking into volume of the oil, the storage time and the antioxidant properties of the additives. The oils were stored under the same conditions, at room temperature and in dark, over a four-week period.In oils without additives, continuous oxidation begins right after opening. Smaller volume oils have a higher peroxide value than higher volume oils. After the fourth week, the peroxide value of smaller volume oils without additives is above the permissible limitsin accordance with the Rulebook. Peroxide values in all analysed oils with added rosemary and parsley are exceptionally low and below the permissible limits according to the Rulebook. In oils with added rosemary, oxidation begins after the third week. In oils with added parsley, oxidation begins after the second week. The peroxide value is directly proportional to the period in storage of cold pressed oil, and inversely proportional to the volume of oil in the bottle.There is a difference of statistical significance between the peroxide value of oils without additives and the oils with added rosemary and parsley.Rosemary and parsley as natural antioxidants added to analyzed oils greatly reduce the oxidation process.