Green extraction procedures of lipids from Tunisian date palm seeds

This study was performed to compare, in term of quality and quantity, conventional and green lipid extraction procedures of three Tunisian date palm (Phoenix dactylifera L.) seeds cultivars (Deglet Nour, Allig and Belah). Extractions were performed using n-hexane and 2-methyltetrahydrofuran (MeTHF) as solvents. Identification and quantification of extracted fats and lipids were carried out by gas chromatography coupled with a flame ionization detector and high performance thin-layer chromatography. Results showed that Deglet Nour presents the highest lipids extraction yield (7.24-5.97%) using the both solvents. Hansen solubility simulation demonstrated that MeTHF is a good alternative solvent for lipid date seeds extraction. In addition, extraction of oils from date pits with ultrasound and micro-wave were better in terms of extraction time (30 min versus 8 h) comparing to soxhlet procedure and of extraction yield comparing to maceration (about 6% versus 4%). Triglycerides represent almost the whole recovered oils composition with 99% and the fatty acids were mainly oleic (44.02-46.9%), lauric (20.00-23.10%), myristic (8.88-11.26%), palmitic (9.00-10.73%) and linoleic (6.13-9.21%) acids.