Enhancement of palm oil extraction yield by applying underwater shock wave pre-treatment at different voltage

Abstract

The present work aimed to investigate the effect of underwater shock wave (USW) on palm oil yield. Palm fruits were prepared and treated by applying USW before oil extraction. Strong USWs were generated by discharging high electric voltage into water, and varying the supplied voltage in the range of 2 - 10 kV. Following USW treatment, two methods of palm oil extraction namely screw-press and solvent extraction were used to determine the oil yield. Oil yield extraction and microstructure morphology of palm mesocarp were also investigated. It was found that at 10 kV of the USW treatment, the highest yield of palm oil extraction through screw-press method was 66.35%, while the solvent extraction method yielded 70.38%, which were 3.1 and 6.3% improvement, respectively, as compared to the untreated extraction. Microstructure analysis by scanning electron microscope (SEM) of palm mesocarp showed that the oil cells had significant cracks on the surface following treatment with USW. This confirmed that the application of USW was effective in increasing palm oil yield extraction. With a reliable strength and repetition of the treatment, USW treatment is promising for practical application in the palm oil industry and also other plant oil extraction.