EFFECT OF ROSEMARY EXTRACT ON THERMAL STABILITY OF SUNFLOWER OIL

Abstract

The purpose of this study was to evaluate the effect of rosemary extract (Rosemarinus officinalis L.) on thermal stability of sunflower oil. Samples of sunflower oil and sunflower oil containing 0.1% rosemary extract were subjected to three successive cycles of thermal heating at burning point for 8 hours, followed by cooling at room temperaturefor16 hours. After each cycle, samples of oils were taken for analysis ofdensity, viscosity and FTIR spectroscopy measurements. Analyzed parameters were used as indicators of structural changes in analyzed samples of oils. According obtained results the addition of rosemary extract in sunflower oil effectively protect its triglyceride structure and level of unsaturation during thermal heating and increase its thermal stability. Performed FTIR spectroscopy has indicated the role of rosemary extract as a natural protective agent. Samples of sunflower oil with rosemary extract have shown improved thermal stability compared with pure sunflower oil.