Characterization and Classification of Extra Virgin Olive Oil from Five Less Well-Known Greek Olive Cultivars

The present study comprises the second part of an ongoing study focusing on olive oil from five less well‐known Greek cultivars for three of which there are no data available in the literature regarding their chemical composition. A total of 74 olive oil samples were collected during the harvesting periods 2012–2013 and 2013–2014. Headspace‐solid phase microextraction was applied to determine the olive oil volatile profile. Fifty‐six compounds were identified and semi‐quantified by CG–MS. Furthermore, fatty acid composition, conventional quality parameters and color parameters were determined in an effort to characterize and differentiate olive oils according to cultivar. All samples were characterized as extra virgin olive oils. Data obtained showed significant differences between the cultivars. Multi‐element analysis in combination with chemometrics resulted in a high classification rate of 86.5 % for the combination of volatiles plus color, 89.2 % for the combination of VC plus FA, and 91.9 % for the combination of FA composition plus color plus CQP.     

The Effect of Boron Application on Chemical Characterization and Volatile Compounds of Virgin Olive Oil of Ayvalik Olive Cultivar

In this study, the Ayvalik olive variety, an important and widely grown olive variety in Turkey, was chosen. A month prior to blooming and 2 months prior to harvesting in 2011 and 2012, three different concentrations of boron (100, 150 and 250 ppm) were applied to the olive leaves with or without boron deficiencies. After the application, quality criteria, fatty acid composition, total phenol contents and major volatile compounds of olive oil that was obtained from the harvested olives were investigated. Boron application to the olive trees with boron deficiencies has improved both the amount and the olive oil quality. Experimental results show the significance of boron for olive farming. Application of boron in 150 ppm led to a better olive oil quality by improving fatty acid composition [oleic acid (76.03 %), linoleic acid (9.68 %), linolenic acid (0.56 %), monounsaturated fatty acid (77.24 %)], total phenol content (422.94 ppm) and major volatile compounds [E‐2‐hexenal (43.12 ppm), hexanal (3.02 ppm), Z‐3‐hexenol (1.13 ppm)] in both harvest seasons (2011–2012) and in both olive orchards with or without boron deficiencies.     

The Chemical Properties and Volatile Compounds of Virgin Olive Oil from Oueslati Variety: Influence of Maturity Stages in Olives

The aim of the present work was to investigate the influence of fruit ripening on oil quality and volatile compounds in an attempt to establish an optimum harvesting time for Oueslati olives, the minor olive variety cultivated in Tunisia. Our results showed that many analytical parameters, i.e., peroxide value, UV absorbance at 232–270 nm, chlorophyll pigments, carotenoids and oleic acid contents decreased during ripening, whilst linolenic acid increased. Free acidity remained practically stable with a very slight rise at the highest maturity index. The volatile compounds emitted by the Oueslati olive oil were characterized and quantified by HS‐SPME‐GC‐EIMS. Twenty‐three volatile compounds were identified, mainly aldehydes, sesquiterpenes and esters. The results show variations in the volatile fractions and quality parameters of Oueslati extra virgin olive oil obtained at different olive‐ripening stages. Fifteen sesquiterpenes were identified for the first time in this cultivar, mainly hydrocarbon derivatives, but also oxygenated ones. On the basis of the quality parameters and volatile fractions studied, the best stage of Oueslati olive fruits for oil processing seems to be at ripeness index about 3.0. Indeed, these results suggested the possibility of using sesquiterpenes for olive authenticity and traceability and demonstrated that the volatile fractions can be used as indicators of the degree of ripening of the olives used to obtain the corresponding virgin olive oils.     

沙枣花挥发油的化学成分及其指纹图谱的研究

应用GC /MS -计算机联用技术对沙枣花挥发油的化学成分进行分离、鉴定。共分离出 4 3种化合物 ,鉴定出17种化合物 ,占挥发油总量的 89.3%。应用HPLC -DAD技术建立沙枣花挥发油指纹图谱 ,以相对保留时间和相对峰面积为指标 ,确定了 7个特征峰     

Bioactive Compounds in Virgin Olive Oil of the PDO Montoro-Adamuz

Virgin olive oil (VOO) is generally recognized as a healthy fat because of its fatty acid composition and content in minor compounds but a wide range of these substances can be found in commercial oils. The concentration of compounds with attributed health benefits were analyzed in VOO of the PDO Montoro‐Adamuz. Oleic acid represented around 79 % of the total fatty acids, and the mean squalene and tocopherols concentrations were 5800 and 247 mg/kg respectively. Despite the changes found in polyphenols concentration in the oils analyzed for six consecutive crops, these substances accounted for more than 700 mg/kg. Moreover, the effect of irrigation regime and sun radiation on the content in bioactive substances of these oils was also assessed. No significant differences were detected between oils from trees irrigated ad libitum or rain‐feed. In contrast, the level of tree radiation exerted a great effect on the concentration of bioactive substances in oils. Oils from trees cultivated in a sunny area (south orientation) had a higher percentage of oleic acid and concentration in phenolic compounds than those from shady areas (north orientation). The opposite was detected for tocopherols and squalene which were more concentrated in oils from olives of the shady area. The results obtained in this study point out VOO of the PDO Montoro‐Adamuz as a very healthy fat due to their composition in bioactive substances, in particular their richness in phenolic compounds.     

溶剂蒸馏气相色谱-质谱法研究菜籽油挥发性成分

溶剂蒸馏气相色谱-质谱法是一种有效的检测挥发性物质的研究方法,在本研究中对菜籽油中挥发性成分进行分析：将菜籽油和乙酸乙酯（V／V=2：1）混合溶解后蒸馏出溶剂,同时将蒸馏出来的挥发性组分进行富集,然后加热并用N2吹扫蒸馏液浓缩得到待测液,最后用GC／MS分析检测待测液成分。结果检测到挥发性成分46种,通过NIST 2006标准谱库检索、Wiley数据库和文献比较确定挥发性成分28种,分别是酮类、醛类、烷烃类、烯烃类以及其他少量化合物。     

蜂蜡净油挥发性成分的分析和研究

采用气相色谱 质谱联用技术 ,通过质谱库检索并结合保留指数 ,对蜂蜡净油的挥发性成分进行了定性分析 ;同时采用气相色谱技术 ,对其中的大部分挥发性成分进行了定量分析。共检出 75个组分。主要成分为 :1,8 桉树脑 (1.70 % )、芳樟醇 (6 .5 3% )、乙酸芳樟酯 (12 .5 1% )、乙酸松油酯 (1.85 % )、苯乙酸甲酯 (2 .5 9% )、苯乙酸乙酯 (2 .6 0 % )、苯甲醇 (5 .6 7% )、丁酸苯乙酯 (2 .11% )、洋茉莉醛 (1.0 5 % )、苯乙酸 (14 .79% )、香兰素 (8.0 1% )、苯乙酸苄酯 (10 .97% )、肉桂酸苄酯 (2 .5 5 % )等。     

Modification of Phenolic Compounds and Volatile Profiles of Chemlali Variety Olive Oil in Response to Foliar Biofertilization

The main objective of this work was to study the effects of foliar biofertilizers on individual volatile profiles and phenolic compounds of olive oil (Olea europaea L. cv. Chemlali). Three foliar biofertilizers were used in two successive application seasons: T1 (rich in nitrogen, phosphorus and potassium); T2 (rich in calcium); and T3 (application of both T1 and T2). Results showed that foliar fertilization with T2 increased the phenolic compound contents (e.g., oleuropein aglycone and decarboxymethyl ligstroside aglycone) of Chemlali olive oil. It also enhanced the levels of many volatile compounds responsible for the good flavor of olive oil such as hexanal. However, T1-tested fertilizer led to a significant decrease in the content of phenolic compounds, although they seemed to improve significantly the levels of the majority of volatile compounds, especially hexanal. Based on these results, a significant relationship between plant nutrition and quality of oil was observed. Our results demonstrated a potential positive influence on the concentration of sensory quality compounds under T2 (Ca²⁺-based fertilizer). This result should be considered in the design of foliar nutrient application management strategies for olive trees.     

Impact of Olive Harvesting Date on Virgin Olive Oil Volatile Composition in Four Spanish Varieties

The unique sensory characteristics of extra virgin olive oil (EVOO) depend upon its volatile composition. This work investigates the impact of olive fruit harvesting time and growing location on the volatile composition of the obtained EVOO, on four typical Spanish olive varieties (Cornicabra, Picual, Castellana, Manzanilla Cacereña). Several growing locations within the Madrid region (Spain) are studied to assess the natural variability attributed to the environmental factors. Aroma compounds are analyzed by solid-phase microextraction coupled with gas-chromatography and mass spectrometry, and sensory analysis. A considerable different behavior is observed depending on the olive variety and ripening stage. Statistically significant differences are obtained for volatile compounds biosynthesized from the lipoxygenase pathway and other fatty acid metabolism routes, which results in significant differences in their aroma profiles. Practical applications: These results have practical applicability for the olive oil industry and regulatory bodies. For example, for protected designation of origin EVOOs the aroma profile needs to be consistent over different production lots. The outcome of this research is of interest to the olive oil industry to get a better insight into the expected variability and interactions among cultivars, small pedoclimatic differences within the same broader area, and the harvesting date on the sensory and volatile profile of the resulting EVOO.     

木蝴蝶挥发油成分的研究

用同时蒸馏萃取方法对木蝴蝶中挥发油组分进行了提取，测得木蝴蝶挥发油含量为0．3％，并GC／MS法对挥发油进行了分离和鉴定，确认出18种化合物；用峰面积归一法通过G1701BA化学工作站数据处理和系统得出各化学成分在挥发油中的百分含量为92．35％。     

低温预浓缩系统GC—MS联用测定色拉油油烟气中痕量挥发性有机物

应用低温预浓缩系统GC—MS法对色拉油油烟气进行全分析,方法简便、灵敏度高、仪器检测性能稳定。油烟气中共检出69种挥发性有机化合物,包括脂肪烃、醛、酚、酯、氧杂化合物等多种对人体健康有害的物质,易引起呼吸系统疾病。     

Quantitation of Metals During the Extraction of Virgin Olive Oil from Olives Using ICP-MS after Microwave-assisted Acid Digestion

Trace metals such as Cu and Fe have negative effects on the oxidative stability of olive oils, and consequently, their concentrations are used as quality criterion. Also, maximum levels are established for heavy metals (As and Pb) in olive oils due to their high toxicity. Olive fruits can be contaminated with these metals from soil and air and from the use of pesticides or fertilizers, with the potential contamination of virgin olive oil (VOO) during its extraction from the fruits. This work presents two goals: (a) to optimize an analytical method for the determination of metals in raw olive fruits using an Abencor system; (b) to carry out a preliminary study of the fate of the metals during VOO extraction. The selected metals were quantified in raw olive fruits, and in the olive pomace and VOO obtained after their processing. The metal determination was performed by inductively coupled plasma-mass spectrometry after microwave-assisted acid digestion with HNO₃/H₂O₂. The results showed that most of the metals (at least 90 %) present in the olive fruits were retained by the olive pomace, so obtaining high-quality VOO from the point of view of its metal content.     

Determination of Aroma Profiles of Olive Oils from Turkish Olive Cultivars

This study analyzed volatile aromatic compounds present in the oils of Turkish olive cultivars. The cultivars Gemlik, Ayval?k, Memecik, Domat, Uslu, Halhal?, Kilis ya?l?k, Nizip ya?l?k, Ha?ebi and Karamani were harvested from important Turkish olive‐growing locations, such as Bal?kesir, Bursa, Manisa, Ayd?n, Mu?la, ?zmir, Kilis, Mersin, Hatay and Gaziantep during the 2007–2008 and 2008–2009 growing seasons. Olive samples were collected in two harvest years, at almost the same maturity stage, and processed under the same conditions. Headspace solid‐phase microextraction (HS‐SPME) was used to analyze volatile aroma compounds in the olive oil samples. Forty‐seven compounds were characterized and quantified using gas chromatography‐mass spectrometry/flame ionization detector (GC–MS/FID). The most abundant identified compounds were trans‐2‐hexenal, hexanal and 3‐methyl‐1‐butanol. The trans‐2‐hexenal, hexanal and 3‐methyl‐1‐butanol contents of oil samples varied between 0.86–67.15, 3.93–61.82 and 0.48–84.74 %, respectively.     

Biochemical Characterization of Turkish Extra Virgin Olive Oils from Six Different Olive Varieties of Identical Growing Conditions

Extra virgin olive oils were extracted from six different major olive cultivars (Gemlik, Ayvalik, Domat, Akhisar, Memecik, Arbequina) cultivated in the Aegean region of Turkey. Fatty acid, sterol and tocopherol compositions were analyzed and the results were compared by multivariate statistical analysis. Olive samples were collected from the same orchard in order to limit the contribution of parameters such as climate, soil quality and agricultural practices to the total variance of chemical composition of olive oils. Principal component analysis (PCA) showed that cultivars can be clearly distinguished on the basis of fatty acid and sterol composition. It is of interest to note that palmitoleic acid content of Arbequina, a Spanish cultivar, is significantly (p < 0.05) higher than the local Turkish cultivars in question and it is the only olive sample whose palmitoleic acid concentration is higher than that of the stearic acid concentration, exhibiting a divergent composition from the local Turkish cultivars. β‐Sitosterol and Δ5‐avenasterol contents of the oils are significantly correlated (r = ?0.989, p < 0.05) and this results in a discriminative axis on the PCA loading plot. Tocopherol composition was relatively insufficient in discriminating the olive varieties. Regarding tocopherol compositions Gemlik cultivar is distinguished from other cultivars with its γ‐tocopherol content, which is in average two times higher than that of other cultivars. The result of the present compositional study provides important data which can be used for olive oil authenticity studies in Turkey.     

海南香草兰萃取物挥发性成分的GC／MS分析

用 90 %乙醇从香草兰豆荚中萃取香味物质 ,并用GC/MS分析其挥发性化学成分 ,鉴定出 19个已知化合物 ,其中醛类 5个 ,酯类 4个 ,醚类 2个 ,烷烃 4个 ,烯烃 2个 ,脂肪酸 2个。萃取物挥发性成分中 ,香兰素的相对含量最高 ,为2 9 .95 %。     

First Application of Newly Developed FT-NIR Spectroscopic Methodology to Predict Authenticity of Extra Virgin Olive Oil Retail Products in the USA

Economically motivated adulteration (EMA) of extra virgin olive oils (EVOO) has been a worldwide problem and a concern for government regulators for a long time. The US Food and Drug Administration (FDA) is mandated to protect the US public against intentional adulteration of foods and has jurisdiction over deceptive label declarations. To detect EMA of olive oil and address food safety vulnerabilities, we used a previously developed rapid screening methodology to authenticate EVOO. For the first time, a recently developed FT-NIR spectroscopic methodology in conjunction with partial least squares analysis was applied to commercial products labeled EVOO purchased in College Park, MD, USA to rapidly predict whether they are authentic, potentially mixed with refined olive oil (RO) or other vegetable oil(s), or are of lower quality. Of the 88 commercial products labeled EVOO that were assessed according to published specified ranges, 33 (37.5%) satisfied the three published FT-NIR requirements identified for authentic EVOO products which included the purity test. This test was based on limits established for the contents of three potential adulterants, oils high in linoleic acid (OH-LNA), oils high in oleic acid (OH-OLA), palm olein (PO), and/or RO. The remaining 55 samples (62.5%) did not meet one or more of the criteria established for authentic EVOO. The breakdown of the 55 products was EVOO potentially mixed with OH-LNA (25.5%), OH-OLA (10.9%), PO (5.4%), RO (25.5%), or a combination of any of these four (32.7%). If assessments had been based strictly on whether the fatty acid composition was within the established ranges set by the International Olive Council (IOC), less than 10% would have been identified as non-EVOO. These findings are significant not only because they were consistent with previously published data based on the results of two sensory panels that were accredited by IOC but more importantly each measurement/analysis was accomplished in less than 5 min.     

生姜挥发油的GC/MS分析

采用气相色谱－质谱联用技术,对广西百色生姜挥发油进行了定性、定量分析,共分离２２种成分,鉴定了其中的１９种成分结构,其含量占挥发油总量的９７．２９％     

Characterization of the Volatile, Phenolic and Antioxidant Properties of Monovarietal Olive Oil Obtained from cv. Halhali

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 μg 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.     

花椒挥发油化学成分的GC/MS分析

文章采用常规水蒸气蒸馏法提取花椒的挥发油,经气相色谱-质谱技术分离和鉴定,用归一化法测定其相对百分含量,可得花椒挥发油的主要成分为β-月桂烯（1.94192％）、柠檬烯（12.25932％）、沉香醇（14.96057％）,α,α,4-三甲基-3-环己烯-1-甲醇（13.3886％）,2-氨基苯甲酸-3,7-二甲基-1,6-辛二烯-3-醇酯（20.0481％）,乙酸松油酯（5.8074％）.     

Adulteration and Presence of Polycyclic Aromatic Hydrocarbons in Extra Virgin Olive Oil Sold on the Brazilian Market

Seventy samples sold in the Brazilian market as extra virgin olive oil (EVOO) were evaluated for the presence of the 13 polycyclic aromatic hydrocarbons (PAH) classified as carcinogenic and genotoxic by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), to verify if the products were adulterated and to evaluate if there is a correlation between PAH presence and adulteration. PAH were detected in 93% of the samples, with summed levels varying from not detected to 41.10 μg/kg. Five samples showed BaP concentration above acceptable levels set by European legislation and by Brazilian regulation (2.0 μg/kg) and 7 presented PAH4 levels above the limit set by European legislation (10.0 µg/kg). The levels of fatty acid composition, sterols content, stigmastadiene and specific extinction did not comply with both Brazilian and International Olive Council (IOC) standards in 18, 31, 30 and 21% of the samples, respectively. The tolerance levels for these analyses in the Brazilian standards are 55.0–83.0 g/100 g (oleic acid), 3.5–21.0 g/100 g (linoleic acid), ≤0.05 g/100 g (trans-oleic acid), ≤0.05 g/100 g (trans-linoleic + trans-linolenic acid), ≤0.15 mg/kg (stigmastadiene), ≤2.50 (K232), ≤0.22 (K270), ≤0.01 (?K), 1000–1600 mg/kg (Σ sterols). Results indicate that 19 samples were adulterated. According to principal component analysis, samples were distinguished as: (1) EVOO with addition of vegetable oil from another source, (2) EVOO with addition of refined oil and (3) samples possibly not adulterated. The variable ΣPAH was related mainly to samples of EVOO with addition of vegetable oil from another source.