LAUSR

This study was aimed to bleach olive and sunflower oils by using conventional and ultrasonic methods. The qualitative and quantities characteristics of the bleached oils were compared. The used ultrasonic bath (150 W, 20 kHz) was set at two levels of temperatures (45 and 60C). Series of tests including of chlorophyll and carotenoid, color, peroxide value, acidity measurements and free fatty acid (FFA) determination were carried out. By application of conventional bleaching a considerable reduction in chlorophyll and carotenoid contents of olive and sunflower oils were observed, while better removal of the pigments was obtained after ultrasonic treatment for 20 and 30 min at 45 and 60C without any significant negative effect on the fatty acid composition. It might be concluded that the ultrasonic bleaching process can be considered as an alternative method for conventional bleaching method since it could decline the time and temperature of bleaching process. Practical Applications Technical information related to the possible effects of application of ultrasonic bleaching on some of quality parameters of olive and sunflower oils was provided by current study. Ultrasonic waves could improve the bleaching process without any destructive effect on the fatty acids profiles. The suggested method can be used in oil refining industry as alternative to current conventional producer due to reduction of the time and temperature of bleaching process.