Effect of Kaolin spray on physicochemical parameters and fatty acids composition of olive oil cv. Zard under Fasa city climatic conditions

The effect of Kaolin on fruit and oil of olive cv. `Zard’ was evaluated in a commercial orchard in Fasa city، Fars Province. Mature olive trees cv. `Zard’ were sprayed with 0، 3 and 6% kaolin after 60 days، 60 and 90 days and 60، 90، 120 days after full bloom. Results showed that kaolin concentration and spraying time had not significant effects on physicochemical parameters but they had significant effects on free fatty acids composition. linoleic acid (14. 49 percent) and linolenic acid (1. 02%) were lowest in the third level of spraying time. Amount of oleic acid، monounsaturated fatty acids to polyunsaturated fatty acids، oleic acid to linoleic acid were higher in oil extracted from trees treated with 3 or 6% kaolin than the untreated trees. Also، oleic acid to linoleic acid (4. 65%)، monounsaturated fatty acids to polyunsaturated fatty acids (4. 2%) were the highest in 6% kaolin with thrice spraying treatment (6% kaolin × thrice spraying) while linolenic acid، palmitic acid، linoleic acid were the lowest in 6% kaolin × thrice spraying. Therefore this study showed fatty acids composition was improved by kaolin spraying.