Morphology characterization and chemical composition of United Arab Emirates date seeds and their potential for energy production

The seeds of a local date palm cultivar from the United Arab Emirates, Allig, were characterized in this study. Soxhlet, Folch, and CO₂ supercritical extraction were employed to obtain oil from Allig date seed (DS) powder composed of 0.1–0.3 mm particles, yielding oil extraction yield percentages of 10.2%, 9.5%, and 9.8%, respectively. The main fatty acid in the extracted oil was saturated stearic acid, comprising 47.9% of the total fatty acid content. After oil extraction, the total metal content in the DSs dropped from 3.2% to 2.8%, suggesting that some metals were extracted with the oil. On the other hand, the average heating value of the DSs increased from 28.55 ± 1.84 to 29.63 ± 1.28 MJ/kg after oil extraction. The average percentages of dehydration moisture, devitalization protein and carbohydrates, devitalization lipids, and solid decomposition in the DSs before oil extraction were 1–2%, 50–55%, 10–15%, and 30–35%, respectively, whereas those for the DSs after oil extraction were 20–25%, 35–30%, 0%, and 35–40%, respectively. As expected, the lipid content dropped after oil extraction. The heat of combustion and extracted oil results indicate that palm DSs, with their relatively high energy densities, have potential as a source of energy, among other notable organic products.