The Effects of Roller Crusher Speed and Mixing Temperature on Quality and Quantity of Extracted Olive Oil, Roghany Variety



To study the mechanical and thermal parameters effective on quality and quantity of olive oil towards an extraction of highly pure oil, the velocity in rps of crushing rollers, at two levels of 6 and 12 (rps) along with the temperature of the mixing unit at three levels of 30, 45 and 60°C were taken into account. Data, obtaind through a factorial experiment of Randomized Complete Block Design (RCBD) were analytically evaluated and compared. A comparison of means as based on Duncan Multirange test was indicative of the fact that: acid and peroxide level of oil increases with an incrase in temperature at the mixing unit, meaning a decrease in the quality of olive oil. Increase in temperature of mixing unit also leads to an increase in moisture content of pumice leading to a decrease in the quantity of oil extracted. An increase in temperature of the mixing unit from 30 to 45°c was followed by an increase in oil content of pumice and leading to an increase in extracted oil. A further increase in temperature of the mixing unit from 45 to 60°C did increase oil content in pumice, but this increase was accompanied by a decrease in total quantity of oil extracted. The least acidity figure was obtained for a roller crusher speed of 12 rps at 30°C. As for peroxide content to be the least there were no significant differences observed among the treatments of 12×30, 12×60 and 6 (rps)×45°C, but the least peroxide content was observed for the treatment 12 rps × 30°C. This led to the conclution that the most suitable velocity of crusher rollers along with the most proper temperature of the mixing unit for an extraction of optimum quantity high quality olive oil would be 12 rps and 30°C respectively. These are the figures finally recommended for efficient quality olive oil extraction