Abstract
Phenolic compounds, antioxidant activities and total phenolic contents of leaves from different olive varieties (Gemlik, Kalamata, YaglA +/- k and SarA +/- ulak) were evaluated after conventional drying at different temperatures (50, 60, 70 and 80 A degrees C). The drying process resulted in non-significant effects on olive leaves. The phenolic contents however, varied with drying temperature. The contents of minor total phenolics in Gemlik, Kalamata and SarA +/- ulak leaves were 1457.6, 1899.3 and 2179.8 mg GAE/100 g, respectively when dried at 60 A degrees C. The highest total phenolic reduction (23.2%) was observed in Kalamata leaves after drying at 80 A degrees C. The major phenolic compounds in olive leaves were gallic acid (101.2-439.7 mg/100 g), 3,4-dihydroxybenzoic acid (66.7-460.4 mg/100 g), (+)-catechin (39.2-667.8 mg/100 g), 1,2-dihydroxybenzene (15.8-584.8 mg/100 g) and quercetin (33.1-277.7 mg/100 g). It was observed that olive leaves from different varieties are rich in phenolic compounds which are sensitive to heat and varied with drying temperature.