Physico-chemical properties, fatty acid composition, essential oil composition and heavy metal contents of raw and roasted coffee bean and oils

The crude lipid contents of raw and coffee beans of coffee canephoraand coffee arabica varieties were found between 9.09 and 9.88% and 7.29% and 7.90%, respectively. Main fatty acids of samples were linoleic with an average percentage of 45.77%, palmitic with 34.49%, followed by elaidic with 7.89, stearic acid with 6.77%. In addition, raw coffea arabica and Coffee canephorabean oils have 44.3% and 43.9% of saturated fatty acids, 7.8% and 7.3% of monounsaturated fatty acids, 54.3% and 54.4% of polyunsaturated fatty acids respectively. In addition, roasted coffea arabica and coffee canephorabean oils have 43.9% and 42.8% of saturated fatty acids, 8.7% and 8.1% monounsaturated fatty acids and 54.9% and 55.9% of polyunsaturated fatty acids, respectively. Heavy metal contents of beans were found higher than those of oil results. Fe, Cu and Zn contents of both bean and oil samples were found high according to other elements. Cu contends of both coffee canephora and coffee arabica bean and oils ranged from 971.7 ppb to 652.4 ppb and 855.6 ppb to 833.7 ppb respectively. Many aromatic and other hydrocarbons, limonene, 2-pentadecanone, cyclodecanol, nonanol, pyri-dine, tetradecanal, tridecanalmethyl pyrazine, which are characteristic compounds of coffee aroma, were identified by applying GC-MS analysis.