Determination of fatty acid and tocopherol compositions and the oxidative stability of walnut (Juglans regia L.) cultivars grown in Serbia

Abstract

Rabrenovic B., Dimic E., Maksimovic M., Sobajic S.,Gajic-Krstajic L. (2011): Determination of fatty acid and tocopherol compositions and the oxidative stability of walnut (Juglans regia L.) cultivars grown in Serbia. Czech J. Food Sci., 29: 74-78.Five cultivars (Sampion, Jupiter, Sejnovo, Elit, and Geisenheim 139) of walnuts (Juglans regia L.) were collected during the 2008 harvest, from Cacak, Central Serbia. Two techniques of oil extraction were implemented -cold pressing and organic solvent extraction. The influence of the implemented methods on the fatty acid composition, tocopherol content as well as oxidative stability was examined. Predominant fatty acids were palmitic, oleic, linoleic, and linolenic acids. The oleic acid content of the oils ranged from 15.9-23.7% of the total fatty acids, while the linoleic acid content ranged from 57.2-65.1% and that of linolenic acid from 9.1-13.6%. The process of oil extraction had no significant effect on the content and composition of fatty acids in the oil. The total content of tocopherols ranged from 28.40 mg/100 g to 42.40 mg/100 g of the extracted oil. The most common tocopherol in all samples was γ-tocopherol. The oil extracted using the Soxhlet method contained higher amounts of total tocopherols while the stability of the oil samples, expresed as induction period, ranged from 5.0 h to 7.1 hours. Reduced stability of the oil samples as measured by the Rancimat method was negatively correlated with the level of linolenic acid and total content of tocopherols.

Physico-Chemical and Antioxidant Characteristics in Fruits of Walnut (<i>Juglans regia L.</i>) Genotypes from Inner Anatolia

“…The total content of tocopherols in the analyzed samples ranged between 30.0 and 44.4 mg/100 g oil, which is comparable with other data published Demir and Cetin (1999), Savage et al (1999), Crews et al (2005). Rabrenovic et al (2011) reported total tocopherol in 5 walnut cultivars grown in Serbia was found between 28.4 and 42.4 mg/100 g. The highest content of total tocopherols was found in 'G-13' genotype fruit oil extracted by the Soxhlet method, while the lowest content was found in the 'G-6' genotype. The cultivar 'Sebin' had 36.9 mg/100 g total tocopherol in oil (Table 3).…”

“…The cultivar 'Sebin' had 55.03%, 14.17%, 19.06% and 7.81% of linoleic, linolenic, oleic and palmitic acid content (Table 2). Rabrenovic et al (2011) revealed that predominant fatty acids in fruits of 5 walnut cultivars ('Sampion', 'Jupiter', 'Sejnovo', 'Elit', and 'Geisenheim 139') grown in Serbia were linoleic (57.2-65.1%), oleic (15.9-23.7%), linolenic (9.1-13.6%) and palmitic acid (6.3-7.7%). Ozrenk et al (2011) determined linoleic acid 50.58-66.60%, oleic acid 14.88-28.71% and linolenic acid 9.16-16.42% among walnut selections.…”

Flash Extraction and Physicochemical Characterization of Oil from <i>Elaeagnus mollis</i> Diels Seeds

“…The tocopherol content in the present study was in accordance with that of walnut oil, in which the contents of total tocopherols and γ-tocopherol were 28.4-42.4 and 25.4-38.4 mg/100 g, respectively 27 .…”

“…, and palmitic 6.3-7.7 acids, and the PUFAs, MUFAs and SFAs in walnut oil ranged in 67.4-75.7 , 15.9-23.9 and 8.3-9.4 , respectively 27 . Sielicka et al studied the compositions of non-refined flaxseed, walnut, rapeseed, pumpkin seed, evening primrose, and black cumin oils.…”

Total Oil Content and Fatty Acid Profile of Some Almond (Amygdalus communis L.) Cultivars

“…In recent studies, it has been suggested that the ratio of oleic acid to linoleic acid could be used as a criterion for determining the almond kernel quality when evaluating oil stability and fatty acid composition [Kodad & The high rate of unsaturated fatty acids can also extend the shelf life of nuts, and has positive effects on human health [Rabrenovic et al, 2011]. Almond is also rich in unsaturated fatty acids [Abdallah et al, 1998;Sathe et al, 2008].…”