n-Alkanes and n-Alkenes in Virgin Olive Oil from Calabria (South Italy): The Effects of Cultivar and Harvest Date

Abstract

n-Alkanes and n-alkenes are components of the unsaponifiable fraction of an olive oil. These were analysed by GC on-column analysis and are here proposed as an additional tool to certify the origin, authenticity, traceability and chemical quality of olive oil produced in the Reggio Calabria province (South Italy). Nine cultivars were studied: Cassanese, Coratina, Itrana, Leccino, Nociara, Ottobratica, Pendolino, Picholine and Sinopolese grown in the region of Calabria (South Italy). n-Alkanes in the range from 21 to 35 chain carbon atoms and alkenes in the range from 23:1 to 25:1 chain carbon atoms were found with the following elution order: heneicosane (C21), docosane (C22), tricosene (C23:1), tricosane (C23), tetracosene (C24:1), tetracosane (C24), pentacosene (C25:1), pentacosane (C25), hexacosane (C26), eptacosane (C27), octacosane (C28), nonacosane (C29), triacontane (C30), entriacontane (C31), dotriacontane (C32), tritriacontane (C33), tetratriacontane (C34), pentatriacontane (C35). The oil of all cultivars showed a decreasing trend in total n-alkane and n-alkene content, with the oil of Sinopolese showing the highest content, varying from 328.50 to 214.00 mg/kg. Odd-chain alkanes predominated over even-chain n-alkanes, and tricosane, tetracosane and pentacosane were the most represented alkanes. Cultivar and harvest date significantly influenced the n-alkane and n-alkene content. These findings can be useful to distinguish different olive cultivars and to decide the fruit harvest date for the oil of the Reggio Calabria province (South Italy). A daily quantity of 30 g of olive oil of the Sinoplese cv (the one with the highest n-alkane and n-alkene content) was found to be in accordance with the suggestions of the European Agency for the evaluation of medicinal products Committee for veterinary medicinal products and biogenic hydrocarbons intake for the human diet.

Controlled Release of Flavor Substances from Sesame-Oil-Based Oleogels Prepared Using Biological Waxes or Monoglycerides

“…Studies conducted on vegetable oils found that the n-alkane composition varied depending on the botanical origin [12]. Sesame oil [13], sunflower oil [14], olive oil [15,16], palm oil [17], peanut oil [14] and linum seed oil [18] all have specific patterns of n-alkane carbon chain length composition and content. For instance, the carbon atom chain of n-alkanes in olive oil [16] ranges from 24 to 260 mg/kg, and the carbon atom chain of n-alkanes in sesame oil [13] ranges from 22 to 82 mg/kg.…”

Therapeutic Properties and Use of Extra Virgin Olive Oil in Clinical Nutrition: A Narrative Review and Literature Update

“…Alkanes and alkenes are mostly odd-numbered, as they come from the loss of a carboxyl group in very-long-chain acids (VLCA), which are initially formed by the fatty-acid elongation complex in the endoplasmic reticulum (using palmitic and stearic acids as substrates) [ 71 ]. The alkane content and profile in EVOO depend on its cultivar [ 72 ], harvest time [ 73 ], and geographical region: the most frequent n -alkanes are n -C25 in continental Europe, n -C23 in north Africa and southern Italy, and n -C29 in the Iberian Peninsula [ 73 , 74 ]. This different geographical location may be related to meteorological conditions, as the intensity of precipitation is associated with larger alkanes and alkenes [ 75 ].…”

Nutraceuticals: Focus on Anti-Inflammatory, Anti-Cancer, Antioxidant Properties in Gastrointestinal Tract

“…Although extra virgin olive oil has a high concentration of oleic acid, its minor components, principally the phenolic compounds, appear to be responsible for the greatest number of its beneficial effects. Moreover, the profile and concentration of these olive oil minor components depend on the cultivar [ 49 ], irrigation [ 50 ], and type of cultivation [ 51 ], all factors which can modify the expression and the content of polyphenols such as oleuropein and hydroxytyrosol. Hydroxytyrosol comes from the hydrolysis of oleuropein that is mostly present in the fruit and in the olive leaves [ 52 ].…”