FATTY-ACID DISTRIBUTION IN POLAR AND NONPOLAR LIPID CLASSES OF HAZELNUT OIL (CORYLUS-AVELLANA L.)

The lipid extract from hazelnuts was classified as polar (glucolipids = 1.4% and phospholipids = < 1%) or nonpolar (triacylglycerides = 98.4 %) by column and thin-layer chromatography. Fatty acids derivatized as methyl esters were analyzed by gas chromatography with flame ionizati on detector and mass spectrometer. Oleic acid was predominant in all l ipid classes, followed by linoleic, palmitic, and stearic. Myristic, p almitoleic, hexadecadienoic, linolenic, eicosanoic, and eicosenoic aci ds were also present in minor proportions. Monounsaturated fatty acids predominated in nonpolar lipids, whereas saturated and polyunsaturate d acids were more prominent in polar lipids. Fatty acid contents were compared by ANOVA. Significant differences were found for fatty acid c ontents in the different lipid classes (p < 0.05). A negative correlat ion was found between monounsaturated-polyunsaturated and monounsatura ted-saturated fatty acids.