Influence of Moisture Content and Seed Dimensions on Mechanical Oil Expression from African Oil Bean (Pentaclethra macrophylla Benth) Seed

Abstract

Purpose: New low-cost oilseeds are needed to meet an ever-increasing demand for oil for food, pharmaceutical, and industrial applications. African oil bean seed is a tropical crop that is underutilized and has high oil yields, but there have been no studies conducted on its mechanical oil expression up to now. The objective of this work was to investigate the effect of moisture content and seed dimensions on mechanical oil expression from the seeds. Methods: Fresh oil bean seeds were procured, de-hulled, and cleaned. Initial seed moisture content, obtained in accordance with the ASAE standard, was 12% dry basis (db). The seeds were further conditioned by dehydration and rehydration prior to oil expression to obtain four other moisture levels of 8, 10, 14, and 16% db. The major diameter of the seeds was measured using digital vernier calipers, and the seeds were classified into size dimensions (< 40, 41-45, 46-50, 51-55, and > 55 mm). The oil yield and expression efficiency were obtained in accordance with standard evaluation methods. Results: The highest oil yield and expression efficiency (47.74% and 78.96%, respectively) were obtained for a moisture content of 8% db and seed dimensions of < 40 mm, while the lowest oil yield and expression efficiency (41.35% and 68.28%, respectively) were obtained for a moisture content of 14% db and seed dimensions between 51-55 mm. A mathematical model was developed to predict oil yield for known moisture content and seed dimensions, with a coefficient of determination R 2 of 95% and the confidence level of the predictive model of 84.17%. The probability of prediction F ratio showed that moisture content influence was more significant than seed dimensions. Conclusions: The higher the moisture content and larger the seed dimensions, the lower the oil yield from African oil bean seeds.

Influence of processing conditions on some physical characteristics of vegetable oil expressed mechanically from Pentaclethra macrophylla Benth kernels: Response surface approach

“…Oils can be obtained from seeds chemically using solvents or mechanically using set of devices like hydraulic press and oil expellers. Solvent extraction method is very efficient; it extracts approximately 98% oil though with the disadvantage of sophisticated equipment, high cost of investment, and technical expertise (Aremu & Ogunlade, , ; Aremu, Ibrahim, & Bamidele, ; Bargale, ; Bargale, Wulsfohn, Irudayaraj, Ford, & Sosulski, ; Bargale et al, ; Ibrahim & Onwualu, ).…”

“…Independent variables that influence the quality and quantity of vegetable oil expressed mechanically include processing parameters like heat applications (duration and temperature) (Aktas, Gerçekaslan, & Uzlaşır, ; Raba, Chambre, Copolovici, Moldovan, & Copolovici, ; Rahma, Zekhnini, El‐Alem, & Hatimi, ) and moisture content (Fakayode & Ajav, ; Pornpipat, Hattha, & Tantanawat, ; Sarah, Widyastuti, & Ningsih, ; Udoh, Olayanju, Dairo, & Alonge, ; Zheng et al , ). Literature is very scanty on the effect of variables affecting the quality (yield) and quantity (characteristics) of vegetable oil expressed mechanically from African oil bean kernels (Aremu & Ogunalde, , ). Thus, this study aims to summarize the physical characteristics of vegetable oil as affected by processing conditions when expressed mechanically from African oil bean kernels.…”

Postharvest processing, packaging and storage of African oil bean seed

“…In addition, [36] found the angle of repose and friction coefficient to be 17.20 o and 0.31, respectively. In their own work, [3] investigated the mechanical properties of the seed at moisture content range of 15.76 to 34.43% wet basis and loading rate of 25 mm/min., and they found the values of rupture force, toughness, rupture stress, yield force and modulus of stiffness of the seeds to decreased linearly from 362.04 to 168.82 N, 1.783 to 0.623 J, 7.4 to 3.15 N/mm 2 , 213.42 to 89.68 N and 39.6 to 21.97 N with moisture increase in transverse axis. Whereas for longitudinal loading, the values decreased from 276.64 to 195.26 N, 1.355 to 0.641 J, 16.12 to 6.23 N/mm 2 , 211.58 to 124.72 N and 38.74 to 24.77 N with an increase in moisture content.…”

“…Whereas for longitudinal loading, the values decreased from 276.64 to 195.26 N, 1.355 to 0.641 J, 16.12 to 6.23 N/mm 2 , 211.58 to 124.72 N and 38.74 to 24.77 N with an increase in moisture content. The seeds' physical and mechanical properties were affected by moisture content [3,35]. However, it was observed that adequate work had not been done on the thermal properties of the seeds despite the fact that heat treatment is essential for its processing.…”

Effect of Pre-treatment on Quality Attributes of Pentaclethra macrophylla Benth Oil Expressed using an Oil Expeller: A Response Surface Approach

“…The treated kernels were covered in closed polythene packs and stored under cold conditions for 2 days to promote uniform mix of moisture. Kernels were roasted in heating segment of the oil expeller Ogunlade, 2016a and2016b;Ogunlade and Aremu, 2019;2020) at different time and temperatures intervals (Table 1), oil samples obtained were untouched for 4 days prior to further experimentations (Weiss, 2000)…”