Cold Hydraulic Extraction Optimization and Characterization of Balanites aegyptiaca and Ceiba pentandra Seed Oils

Abstract

Non-edible vegetable oils have a huge potential for many industrial applications. Most of them are expressed by mechanical pressing, but data on the different operating conditions to achieve optimal extraction yields and high-quality oil are scarce. Hence, the objective of this study was to optimize key hydraulic extraction parameters at ambient temperature (25 °C) of <em>Balanites aegyptiaca</em> and <em>Ceiba pentandra</em> oils by increasing the oil recovery. Optimal holding time, applied pressure, compression speed, and press cage charge were determined for whole and crushed oleaginous material. The results indicate that the <em>B.aegyptiaca </em>kernels and <em>C.pentandra</em> seeds contained 2.7 and 5.7% moisture, as well as 46.3 and 26.2% fat, respectively. Under the optimal operating conditions, the oil recovery (wt.%. d.b.) from whole (crushed) material was 73.4 (69.8) <em>B.aegyptiaca </em>kernels and 38.2 (41.2) <em>C.pentandra</em> seeds.<strong> </strong>The extracted oils have a high content of unsaturated fatty acids including of about 74 wt.% for <em>B. aegyptiaca</em> and 69 wt.% for <em>C.pentandra</em>. They were particularly rich in linoleic ω-6 acid, 45.32 and 38.77 wt.%, respectively. The chemical characteristics of cold-extracted <em>B. aegyptiaca</em> and <em>C.pentandra</em> oils were 10 and 20 ppm phosphorus, 2.8 and 3.5 ppm iron, 0.0 ppm copper, 0.06 and 0.1% water-volatile matter, respectively. These valuable material properties make the <em>B.aegyptiaca</em> and <em>C.pentandra</em> oils an ecological and renewable resource for multipurpose applications.