Enhancement of Antioxidants in Olive Oil by Foliar Fertilization of Olive Trees. (22nd June 2013)

• Record Type: Journal Article
• Authors: Tekaya, Meriem; Mechri, Beligh; Bchir, Amani; Attia, Faouzi; Cheheb, Hechmi; Daassa, Mohamed; Hammami, Mohamed
• Is Part Of: Journal of the American Oil Chemists' Society. Volume 90:Number 9(2013)
• Page Start: 1377
• Page End: 1386
• Publication Date: 2013-06-22
• Subjects: Foliar fertilization -- Olive oil quality -- Oxidative stability -- Antioxidants; Oils and fats -- Periodicals; Soap -- Periodicals; Fats -- Periodicals; Food-Processing Industry -- Periodicals; Acides gras -- Périodiques; Aliments -- Industrie et commerce -- Périodiques; Huiles et graisses -- Périodiques; Savon -- Périodiques; Oliën; Chemie; Oils and fats; Soap; Periodicals; 547.77
• DOI: 10.1007/s11746-013-2286-0
• Languages: English
• ISSNs: 0003-021X

Abstract

Abstract: Oxidative stability (OS) of virgin olive oil is affected by different antioxidants whose levels may be influenced by nutrients availability. Changes in OS of virgin olive oil and antioxidants levels were evaluated according to foliar application of six nutrient‐based treatments: T1 (rich in nitrogen), T2 (rich in boron, magnesium, sulfur and manganese), T3 (rich in phosphorus and potassium), T4 (rich in phosphorus and calcium), T5 (application of T1 and T2) and T6 (application of T1, T2, T3 and T4). The foliar applications were carried out during two successive growing seasons and oils were extracted and analyzed at the end of the experiment (after 2 years). T3 and T6 treatments improved oil stability by increasing the content of antioxidants, while T2 and T4 affected negatively the antioxidant profile of oils. Measured correlations between OS and compositional variables showed that total phenols had the highest value ( R = 0.937, p < 0.001), followed by α‐tocopherol ( R = 0.775, p < 0.001) and oleic/linoleic ratio ( R = 0.625, p < 0.05). These findings suggest that the changing levels of antioxidant compounds, due to fertilization, may be used to obtain oils with the highest quality.