A Kinetic‐Thermodynamic Study of the Effect of the Cultivar/Total Phenols on the Oxidative Stability of Olive Oils

Extra virgin olive oil is recognized as a very stable oil because of its composition in fatty acids and its content in natural antioxidants (tocopherols and polyphenols). In the bibliography are works that address different aspects of this stability, from the duration of its useful life to its performance in the frying of foods. Some works also link their stability with the content of natural antioxidants. For example, Franco et al. (2014) studied the content of phenols and their antioxidant capacity in olive oils of seven different varieties. Baccouri et al. (2008) found a good correlation between the oxidative stability (measured in Rancimat) of the oils studied and the concentration of total phenols and tocopherols.

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Characterization of commercial Tunisian monovarietal olive oils produced from autochthonous olive cultivars

Emirates Journal of Food and Agriculture ◽

10.9755/ejfa.2018.v30.i7.1741 ◽

2018 ◽

pp. 581

Author(s):

Souihli Slim, Nuno Rodrigues ◽

Ana C.A. Veloso ◽

Luis G. Dias ◽

Rebeca Cruz, Susana Casal ◽

Souheib Oueslati ◽

...

Keyword(s):

Fatty Acids ◽

Oxidative Stability ◽

Monounsaturated Fatty Acids ◽

Storage Conditions ◽

Total Phenols ◽

Olive Cultivar ◽

Linear Discriminant ◽

Discriminant Model ◽

Olive Oils ◽

Olive Cultivars

Tunisian commercial monovarietal olive oils, produced from two predominant autochthonous olive cultivars (cvs Chétoui and Oueslati) and another less investigated olive cultivar (cv Sahli) were studied. Chemical and sensory data have shown that most olive oils should be classified as lampante olive oil, pointing out the need of improving producing and/or storage conditions. Sahli olive oils showed the lowest total phenols content (157±48 mg/kg), oxidative stability (6.5±2.1 h), DPPH scavenging activity (68%±14) and monounsaturated fatty acids content (63.1%±3.1). These olive oils had the highest saturated and polyunsaturated fatty acids contents (19.9%±2.4 and 16.9%±1.4) as well as total tocopherols levels (222±49 mg/kg). Finally, the information of 12 selected parameters (total phenols, oxidative stability, nine fatty acids and γ-tocopherol), allowed establishing a linear discriminant model that correctly classified olive oils according to the olive cultivar with predictive rates of 90%±8. Heptadecenoic, behenic and eicosenoic acids were the three fatty acids identified as the most relevant chemical markers of Sahli olive oils.

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Kinetic-thermodynamic study of the oxidative stability of Arbequina olive oils flavored with lemon verbena essential oil

LWT ◽

10.1016/j.lwt.2020.110711 ◽

2021 ◽

Vol 140 ◽

pp. 110711

Author(s):

Marwa Cherif ◽

Nuno Rodrigues ◽

Ana C.A. Veloso ◽

Khalil Zaghdoudi ◽

José A. Pereira ◽

...

Keyword(s):

Essential Oil ◽

Oxidative Stability ◽

Thermodynamic Study ◽

Olive Oils ◽

Lemon Verbena

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Microwave Heating Effects on the Chemical Composition and the Antioxidant Capacity of Tataouine Virgin Olive Oils from Tunisia

Journal of Food Protection ◽

10.4315/0362-028x-73.10.1891 ◽

2010 ◽

Vol 73 (10) ◽

pp. 1891-1901 ◽

Cited By ~ 2

Author(s):

IMEN OUESLATI ◽

WAEL TAAMALLI ◽

FAOUZIA M. HADDADA ◽

MOKHTAR ZARROUK

Keyword(s):

Oxidative Stability ◽

Microwave Heating ◽

Genetic Factor ◽

Degradation Rate ◽

Treatment Time ◽

Antioxidant Potential ◽

Virgin Olive Oils ◽

Olive Oils ◽

Heating Effects ◽

Total Fraction

Four Tunisian virgin olive oils (VOOs), derived from varieties (Chemlali Tataouine, Zarrazi Douirat, Fakhari Douirat, and Dhokar Douirat) grown in the harsh pedoclimatic conditions of the region of Tataouine, were evaluated for their responses to microwave heating. Aside from fatty acid composition, all other evaluated parameters were affected by microwave heating, and their variations depend on the genetic factor. Chemlali Tataouine VOO exhibited the slowest biophenol degradation rate and the least diminution in oxidative stability and consequently, its total fraction and both lipidic and methanolic fractions remained unchanged with an exceptional antioxidant potential. In the remaining studied VOOs, the biophenol contents, the oxidative stability, and the antioxidant potential underwent gradual decreases; nevertheless, their levels at the longer treatment time are close to some fresh VOOs. These results should be taken into consideration when Tataouine VOOs are recommended for microwave heating.

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