A review of oil point identification and experimental determination of oil content of selected oilseeds

Dipl.-Ing. Achyuth Hanumanthappa meti, Dipl. Ing. dipl. tech.

Bachelor's thesis

Abstract:

The Bachelor Thesis is focused on the theoretical and experimental analyses of oil point and oil content of selected oilseeds namely pumpkin, rape and sunflower. The oil point analysis was based on a literature review where the effects of processing conditions on oil point pressure and mathematical models of oil point of oilseeds were discussed. The oil content analysis was based on an experimental determination using the Soxhlet extraction procedure for cycles between 6 and 24 hrs. The moisture content of the seeds was also determined based on the conventional oven method. Compression of the oilseeds was done at 80 mm pressing height with the vessel diameter of 100 mm with a plunger, speed of 5 mm/min and force of 400 kN where the oil yield, oil expression efficiency and deformation energy were calculated. The percentage oil content of pumpkin seeds increased from 31.60 to 38.34 % at 12 hr to 24 hr cycles and slightly increased from 33.63 to 34.45% at 6 hr to 10 hr cycles. However, at 10 and 12 hr cycles, the oil content of 34.45 % decreased to 31.60%. In comparison with rapeseeds and sunflower seeds, the oil content at the 6 hr cycle was known to be 31.87 ± 2.40 and 33.12 ± 0.87 % respectively. The moisture content at 24 hr of pumpkin, rape and sunflower oilseeds was calculated to be 6.35 ± 0.05, 5.29 ± 0.05 and 4.78 ± 0.01 (% w.b.). Oil expression efficiency of sunflower seeds was the highest (46.74 ± 0.73%) followed by rapeseeds (33.03 ± 1.36 %) and then pumpkin seeds (20.31 ± 0.80 %). The corresponding energies were 2010.79 ± 40.47 J, 2143.51 ± 35.98 J and 1858.42 ± 0.27 J. It was observed that higher energy was required for processing rapeseeds than sunflower and pumpkin seeds. The results of the study provide vital information for conducting comprehensive research on the selected oilseeds among others under uniaxial compression to improve the commonly used mechanical screw oil pressing.

Keywords

Oil point, Soxhlet extraction, compression test, oil yield, oil expression efficiency

Language used: English

Date on which the thesis was submitted / produced: 19. 5. 2021

Thesis defence

• Supervisor: doc. Ing. Abraham Kabutey, Ph.D.
• Reader: Cimen Demirel, Ph.D.

Czech University of Life Sciences Prague

Faculty of Engineering

Bachelor programme:
Agricultural Engineering