Electronic Theses and Dissertation

This research aimed lo study the effect of extraction time. ratio of solvent and temperature on the kinetics of extraction of ginger oleoresin extraction using ultrasonic waves. this research used variables of the extraction temperature (35 ° c, 40 °c and 45 °c), the concentration of ginger to ethanol (1:2, 1:3 and 1:4) and the extraction time (10, 20, 30, 40, 60, 80, 120 and 180 minutes). ultrasonic extraction mechanism occurred in two stages. the first stage was called washing stage and the second stage was called slow extraction. the extraction process was described mathematically by using two models of the unsteady diffusion off film theory. the results of extraction tended to increase with increasing extraction temperature, the amount of solvent and the extraction time, linear correlation coefficient average for the unsteady diffusion model and the theory offilm were 0.84 and 0.83 respectively. the physical properties of ginger oleoresin generally already met the standards o/ the essential oil association o/ america (eoa). analysis results using gc-ms showed that the components of ginger oleoresin extracted increased with increasing the temperature of extraction. the highest gingerol composition obtained in the extraction temperature 40 °c was 29.40%. key words: ultrasonic, kinetic, extraction. ginger and oleoresin.