Optimization of Ohmic Heated Oil Extraction from Dabai (Canarium odontophyllum) Pulp using Response Surface Methodology Muhammad Hazwan Hamzah (a, b*), Olivia Janam Dani Lalo (a), Adila Fazliyana Aili Hamzah (a), Rosnah Shamsudin (c), Abd Halim Md Ali (d), Mohd Salahuddin Mohd Basri (c), Hasfalina Che Man (a, b), Sukardi Gatuk Abdulloh (e)
a) Department of Biological and Agricultural Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
*hazwanhamzah[at]upm.edu.my
b) SMART Farming Technology Research Centre, Faculty of Engineering, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
c) Department of Process and Food Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400, Serdang, Selangor, Malaysia
d) Department of Chemical and Environmental Engineering, Malaysia-Japan International Institute of Technology, Universiti Teknologi Malaysia, Jalan Sultan Yahya Petra, 54100, Kuala Lumpur, Malaysia
e) Department of Agro-Industrial Technology, Faculty of Agricultural Technology, Universitas Brawijaya, Jl. Veteran, Malang 65145, Jawa Timur, Indonesia
Abstract
A proposed method for dabai essential oil was developed with the application of ohmic heated extraction (OHE). The extraction process was optimized using response surface methodology based on central composite design. The optimum parameters were determined as reaction time: 15 minutes, voltage: 40 V, temperature: 70C, resulting in dabai pulp oil yield of 22.07%. The reliability of regression model was demonstrated through experiments utilising same optimum parameters, which produced an average oil yield of 23.12%. The dabai pulp oil extracted from OHE yielded higher than Soxhlet method (SE) which yielded 19.49%. The chemical, physical and morphology properties of dabai oil and pulp extracted using both extraction methods were determined. Gas chromatography/mass spectroscopy was performed and results indicated that major constituents of dabai pulp oils for different extraction methods were nonanal, 2-Decenal, nonanoic acid and octanal. The results of refractive index and specific gravity at 20C for OHE and SE were 0.623 and 1.01 and 0.625 and 1.02, respectively. Scanning electron microscopy of dabai pulp of OHE provided evidence pores and agglomerates structure in comparison to SE and raw material. Results of this research revealed that OHE could be introduced as an alternative technology to conventional methods.
