The aroma and aroma-active compounds of olive oils obtained from Nizip Yaglik (NY) and Kilis Yaglik (KY) cultivars and the effect of the geographical area (southern Anatolian and Aegean regions) on these compounds were analyzed by gas chromatography-mass spectrometry-olfactometry (GC-MS-O). For this purpose, two oil samples were obtained from their native geographical area including NY from Nizip province and KY from Kilis province (southern Anatolian region of Turkey). Another two oils of the same cultivar, NY-Bornova (NY-B) and KY-Bornova (KY-B), were obtained from the Olive Oil Research Center-Bornova, Izmir province (Aegean region of Turkey) to compare geographical effect on aroma and aroma-active compounds. Simultaneous distillation and extraction (SDE) with dichloromethane was used for extraction of volatile components. SDE gave a highly representative aromatic extract of the studied olive oil based on the sensory analysis. Totals of 61, 48, 59, and 48 aroma compounds were identified and quantified in olive oils obtained from NY, NY-B, KY, and KY-B cultivars, respectively. The results of principal component analysis (PCA) showed that the aroma profile of native region oils was discriminately different from those of Bornova region oils. Aldehydes and alcohols were qualitatively and quantitatively the most dominant volatiles in the oil samples. Aroma extract dilution analysis (AEDA) was used for the determination of aroma-active compounds of olive oils. The number of aroma-active compounds in native region oils was higher than in Bornova region oils. Within the compounds, aldehydes and alcohols were the largest aroma-active compounds in all olive oils.

Volatile and phenolic compositions of olive oil obtained from the cv. Halhali were investigated in the present study. Fruits were harvested at the optimum maturity stage of ripeness and immediately processed with cold press. Simultaneous distillation/extraction (SDE) with dichloromethane was applied to the analysis of volatile compounds of olive oil. Sensory analysis showed that the aromatic extract obtained by SDE was representative of olive oil odour. In the olive oil, 40 and 44 volatile components were identified and quantified in 2010 and 2012 year, respectively. The total amount of volatile compounds was 18,007 and 19,178 lg kg -1 for 2010 and 2012, respectively. Of these, 11 compounds in the 2010 and 12 in the 2012 harvest presented odour activity values (OAVs) greater than 1, with 1-octen-3-ol, ethyl-3-methyl butanoate, (E)-2-heptenal and (E,Z)-2,4-decadienal being those with the highest OAVs in olive oil. The high-performance liquid chromatographic method coupled with diode-array detection was used to identify and quantify phenolic compounds of the olive oil. A total of 14 phenolic compounds in both years were identified and quantified in olive oil. The major phenolic compounds that were identified in both years were hydroxytyrosol, tyrosol, elenolic acid, luteolin, and apigenin. Antioxidant activity of olive oil was measured using the DPPH and ABTS methods.

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Aroma, aroma‐active compounds and fatty acid profiles of Iranian olive oil obtained from the cv. Mari were investigated for the first time in the current study. Aroma extracts were isolated from the oil by using a purge and trap extraction system and their compositions were analyzed by gas chromatography‐mass spectrometry‐olfactometry (GC–MS‐O). A total of 35 aroma compounds comprising alcohols, aldehydes, acids, esters, ketones, terpenes and volatile phenols were identified and quantified in the assayed samples. Aldehydes were present at the highest levels, followed by ketones and alcohols. (E)‐2‐Hexenal was quantitatively (1589 µg kg−1) the main aroma compound in the analyzed oils, followed by hexanal and (E)‐2‐heptenal. The aroma‐active volatiles were elucidated in the aromatic extract by applying aroma extract dilution analysis (AEDA). The results of AEDA revealed 17 aroma‐active compounds. Under these condition it was possible to completely identify 16 of these compounds. Regarding to the flavor dilution (FD) factor, the most potent odorants with the highest FD factor were (E)‐2‐hexenal (512), followed by hexanal, 6‐methyl‐5‐hepten‐2‐one, (E)‐2‐decenal and one unknown compound (LRI = 1871). The fatty acid profile of the tested oils was composed of thirteen compounds. Oleic acid was the main fatty acid (76.01 %) followed by palmitic acid.

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The aroma and fatty acid compositions of selected Iranian nut oils including bitter almond, sweet almond, walnut, and hazelnut oils are analyzed. The volatile compounds are extracted using purge and trap extraction and identified by gas chromatography–mass spectrometry (GC–MS). In total, 21, 24, 25, and 37 aroma compounds are detected in extracts of bitter almond, sweet almond, walnut, and hazelnut oils, respectively. A total of 54 different volatile compounds composed of aldehydes, alcohols, terpenes, carboxylic acids, pyrazines, ketones, furans, and lactones are identified and quantified. Among them, aldehydes present the highest quantity of the overall volatiles in all samples, followed by terpenes in bitter and sweet almond oils, alcohols in walnut oil, and carboxylic acids in hazelnut oil. In addition to aroma compounds, a total of 15 fatty acids are identified and quantified in all oils. Among them, oleic acid in bitter almond, sweet almond, and hazelnut oils, while linoleic acid in walnut oils show the highest concentration. In addition, oleic acid is more dominant in hazelnut oil (80.48%) than the others. The findings of principal component analysis (PCA) exhibits that oils are discriminately different from each other according to fatty acids and aroma profiles. Practical Applications: Nut oil is one of the most widely consumed oils in Iran. The outcomes of this first investigation provide valuable information for understanding the aroma differences between oils of four well‐known Iranian nuts. The purge and trap extraction set for separation followed by analysis and identification of those compounds by gas chromatography–mass spectrometry is an effective practical application tool for volatile description in valuable and expensive oil samples. It is observed that the aroma profiles of four samples are quite different than each other. This research provides valuable information to understand the fatty acids and aroma profile of the four well‐known Iranian nut oils (walnut, hazelnut, bitter and sweet almond oils). Based on the results, sweet and bitter almond oils can be described with relatively similar flavor characteristics due to terpene and aldehyde groups, but hazelnut and walnut oils have different aroma profiles depending on other chemical groups. It can be said that walnut oil is associated with alcohols and furans, while hazelnut nuts oil with acids, lactones, pyrazines, and ketones.

The purpose of this investigation was to evaluate and compare the differences in the phenolic fractions and antioxidant properties of virgin olive oils from the Nizip yaglik and Kilis yaglik olive varieties cultivated in native and different olive growing areas of Turkey. The phenolic composition of olive oils was carried out by HPLC‐DAD and identifications were made by LC–MS. Fourteen phenolic compounds were identified and among these compounds elenolic acid, tyrosol and hydroxytyrosol were the most dominant. Based on the results, there was no difference in distribution of phenolic compounds, but the total phenolic content in oil from native regions was higher than in oil from Bornova regions. The antioxidant capacity of olive oil extracts was determined by two different methods, including DPPH and ABTS. In both methods, antioxidant capacity values were higher in oil from native regions.