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1.
Federica Flamminii Elettra Marone Lilia Neri Luciano Pollastri Angelo Cichelli Carla Daniela Di Mattia 《European Journal of Lipid Science and Technology》2021,123(11):2000382
Despite the fact that Italy holds the most important olives heritage in the world, with about 800 cultivars, most of them are still underestimated, in particular those from Abruzzo, a region located in the center of the peninsula. The aim of this work is to study the changes in quality parameters of olive fruits and related oils of two autochthonous Abruzzo olive cultivars, Tortiglione and Dritta during ripening (from September to November 2017). Both cultivar and ripening time affect the chemical parameters of olive fruits. Results highlight an increasing trend of the oil content with final values, based on fresh matter, of 38.7 ± 0.3% and 38.1 ± 0.9% for Tortiglione and Dritta, respectively. Olive oils chemical composition is also affected by ripening time and cultivar, with Tortiglione oils resulting generally richer than Dritta oils; on the first sampling time (30th of October) values for total phenolic content, antioxidant activity, and chlorophylls are 803.8 ± 68.2 mg gallic acid equivalent kg−1, 2.7 ± 0.5 mmol trolox equivalent kg−1, and 30.8 ± 1.6 mg pheophytin a kg−1, respectively. Tocopherols seem to be more affected by ripening time than by cultivar, in particular for Dritta. Practical Application : The results on Abruzzo minor olive cultivars indicate that olive fruits and olive oil composition are strongly influenced by both cultivar and ripening time, giving rational indications about the optimal cultivar specific harvesting time and opening interesting opportunities for olive oil producers in a perspective of sustainable production to obtain high quality fruits and oils. The research provides detailed information about Tortiglione and Dritta olive cultivar, useful in the global context of revaluation of Italian minor olive varieties. 相似文献
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3.
Francisco J. Hidalgo Manuel Alaiz Rosario Zamora 《Journal of the American Oil Chemists' Society》2002,79(7):685-689
Twenty-eight virgin olive oils—from different regions of Spain and prepared from olive drupes of different varieties—and six
refined olive oils were analyzed to determine the presence of proteins in these oils. All oils studied showed the presence
of proteins in the range of 7–51 μ/100 g of oil. There were no significant differences in protein content in oils from different
varieties or between virgin or refined oils. In addition, all oils exhibited analogous amino acid patterns, suggesting a similarity
among protein fractions obtained from different oils. A polypeptide with an apparent M.W. of 4600 Da was common to the isolated
protein fractions. These results suggest that this polypeptide is a previously unknown minor component in olive oils. No clear
influence of this component on oil stability was observed when oil stabilities were estimated as a function of phenol, tocopherol,
phosphorus, and protein contents of the oils. 相似文献
4.
Xiaofei Lü Junyi Ma Huiqiang Yan Lihua Yang Xiaoxia Ren Junwei Guo Qiaoning Yong Weibao Kong Yu Deng 《Journal of the American Oil Chemists' Society》2021,98(11):1045-1056
The main purpose of this work was to study the effect of different ripening degree (0–7) on quality of two monovarietal olive oils (Arbequina and Arbosana) produced in Longnan region, located in the northwest of China, Gansu province. The qualitative characteristics of oils are evaluated by analysis of the principal quality parameters and chemical composition, such as: free acidity, peroxide value, K232, K270, oxidative stability, fatty acid composition, total phenols, flavonoids content and flavor profile. The maximum oil yields were obtained for both varieties at a ripening degree of 7 (13.26% and 23.59%). The Arbequina and Arbosana oils contained oleic acid (ranged 53.16%–58.92% and 66.30%–74.30%, respectively) and linoleic acid (ranged 15.51%–18.77% and 7.25%–9.45%), respectively. The ratio of MUFA/PUFA ranged from 2.93 to 3.77 and 6.73 to 9.84, respectively. The ratio of 18:1/18:2 presented ranges of 2.84–3.79 and 7.02–9.94, respectively. A significant relationship was observed between the total polyphenols (83.48–140.53 and 118.32–230.00 mg GAE⋅kg−1), flavonoids (0.43–9.00 and 10.20–5.51 mg RE⋅kg−1) and the oxidative stability. E–Nose could effectively identify and distinguish between different varieties and ripening degree of olive oil, especially that change in the W1W (sulfur-organic) sensor. A principal component analysis showed that the particular effect of ripening degree in the cultivars olive oils. 相似文献
5.
Rocco Mafrica Amalia Piscopo Alessandra De Bruno Paolo Pellegrino Angela Zappia Rocco Zappia Marco Poiana 《European Journal of Lipid Science and Technology》2019,121(11)
Olive ripening, climate conditions, geographic area, and cultivar may influence the composition and quality of olive oils. This study aims to identify the optimal harvesting period for qualitative production of three cultivars grown in Calabria. The obtained results show that all the olive oils produced in October are classified as extra virgin, and then their quality decreases gradually, in particular in Grossa di Gerace olives, grown in a typical hot‐dry area. Oleic acid content in the oil is related to the temperature exposition during fruit growth. Considering oil yield and quality, the optimal harvesting times are identified in the first part of the month of October (142–158 days after full bloom) for Grossa di Gerace olive and in the second and last week of October (142–165 days after full bloom) for Ottobratica and Sinopolese. Practical Applications: This study investigates with a holistic approach the development and maturation of drupes and the quality of oils obtained at two harvesting times. The strong correlation between olive ripening index and the other studied parameters prove that it is a valid index for olive growers to identify the optimal harvesting period for the three Calabrian olive cultivars. To obtain high mechanical harvest efficacy, this study suggests the use of trunk shakers to Grossa di Gerace olives and mechanical beaters to Ottobratica and Sinopolese. 相似文献
6.
M. Andjelkovic S. Acun V. Van Hoed R. Verhé J. Van Camp 《Journal of the American Oil Chemists' Society》2009,86(2):135-140
Although large amounts of olive oil are produced in Turkey, not much information on its chemical composition is available
in the literature to date. The aim of this study was to evaluate the chemical composition of commercial olive oils produced
from the Ayvalik olive cultivar in Canakkale, Turkey. Five different samples corresponding to the olive oil categories of
extra virgin (conventional, extra virgin olive oil (EVOO), and organic extra virgin olive oil (OGOO) production), virgin olive
oil (OO-1), ordinary virgin olive oil (OO-2) and refined olive oil (RFOO) were evaluated. Olive oils were collected from two
consecutive production years. According to the free fatty acids, the absorbance values (K232 and K270), and peroxide values of all the samples conformed to the European standards for olive oil. The level of oleic acid was in
the range of 68–73%; while the linoleic acid content was significantly lower in the refined olive oils. The tocopherol and
polyphenol content was in the lower range of some European olive oils. However, pinoresinol was a major phenolic compound
(5–77 mg/kg depending on the oil category). Its content was markedly higher than in many other oils, which would be a useful
finding for olive oil authentication purposes. 相似文献
7.
Bioactive Compounds of Portuguese Virgin Olive Oils Discriminate Cultivar and Ripening Stage
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Fátima Peres Luisa L. Martins Miguel Mourato Conceição Vitorino Suzana Ferreira-Dias 《Journal of the American Oil Chemists' Society》2016,93(8):1137-1147
The presence of different bioactive compounds in virgin olive oil affects its nutritional, oxidative and sensorial properties. Phenolic compounds are olive endogenous bioactive compounds highly susceptible to degradation. Olive endogenous oxidoreductases, mainly polyphenol oxidases (PPO) and peroxidases (POD), may play an important role on the profile of bioactive compounds in olive oil by promoting oxidation of phenolic compounds. The aim of this study was to evaluate if changes on PPO and POD activities in olive fruits from two Portuguese cultivars (Olea europaea, cv ‘Cobrançosa’ and cv ‘Galega Vulgar’) are related with the composition of their olive oils, especially phenolic compounds. Pattern recognition techniques [principal component analysis (PCA), cluster analysis (CA), and discriminant analysis (DA)] were used for multivariate data analysis. Olive oils characterized by their FA composition were grouped by cultivar. When olive oils were characterized by their phenolic composition, green pigments, and enzymatic activities in fruits, they could be discriminated by olive ripening stage. Along ripening, PPO activity was only detected in the fruit mesocarp of both cultivars and POD activity was mainly detected in the seeds. The POD activity, as well as vanillin and gamma‐tocopherol contents in olive oil increased with the ripening index. Conversely, higher PPO activity in fruits at early ripening stages together with higher levels of total phenols, green pigments, beta‐tocopherol, hydroxytyrosol and p‐coumaric acid in olive oils were observed. The ripening stage of fruits showed to be a key factor on the amount and profile of bioactive compounds of olive oil. 相似文献
8.
Paride Papadia Laura Del Coco Innocenzo Muzzalupo Marco Rizzi Enzo Perri Gianluigi Cesari Vito Simeone Donato Mondelli Francesco P. Schena Francesco P. Fanizzi 《Journal of the American Oil Chemists' Society》2011,88(10):1463-1475
Mono-varietal extra virgin olive oils were micro-extracted from drupes that were selectively collected from 28 trees distributed
in five different Southern Italian Apulian areas. Nuclear Magnetic Resonance (NMR) profiles of these oil samples were correlated
to the genetic (young green material) and soil (samples collected within the foliage projection) data of the tree of origin.
Genetic analysis, performed on the samples using SSRs (Simple Sequence Repeats) by 9 microsatellite loci, confirmed the specific
cultivar assignment (among Cima di Mola, Coratina, Ogliarola, and Oliva Rossa cultivars). Chemometric methods applied to 1H-NMR spectroscopic data were used for cultivar and geographical origin discrimination of the studied extra virgin olive oils.
Linear Discriminant Analysis (LDA) afforded a high reliability degree for discriminating cultivars (almost 90% of prediction
ability), and a good assigning ability for the geographical origin (Ogliarola and Coratina samples used as subsets). Soil
analyses were performed for each tree. Regression analysis was applied to soil composition in order to correlate available
nutrients and total metals with the content of fatty acids and minor components present in monovarietal extra virgin olive
oils. In the case of oleic and linoleic fatty acids, and for some terpenes, B, Cr, Mn, Zn were found to give significant correlations.
Zn and Mn were the most significant trace elements for all the correlations found (p < 0.01). The results obtained (genetic, spectroscopic and soil analyses) are discussed as a multidisciplinary approach for
setting up a strategy for a cultivar and/or geographic origin certification committed database construction. 相似文献
9.
Three hundred (experiment I) and 350 (experiment II) weanling, 3-week-old male Sprague-Dawley rats weighing between 40–50
g were randomly assigned two per cage and 50 per dietary treatment to study the effect of dietary fatty acid balance on myocardial
lesions. The following oils were tested: Experiment I.Brassica napus var. Tower rapeseed oil [Tower RSO, 1974 cultivar and 1975 cultivar, each containing 0.3% erucic (22∶1) acid];B. napus var. Zephyr RSO containing 0.9% 22∶1; corn oil; olive oil; and soybean oil. Experiment II.B. napus var. Tower RSO (1974 cultivar), olive oil, soybean oil, and the following oils to which was added the indicated level of
free 22∶1; Tower +0.5% 22∶1; Tower +5.6% 22∶1; olive oil +4.4% 22∶1; soybean oil +5.7% 22∶1. In each case the oils were incorporated
in a semisynthetic diet at a level of 20% by weight. Heart and heart lipid weights of rats fed the different oils did not
differ statistically from each other. Fatty acid analyses of heart lipids revealed that the fatty acid composition of the
cardiac lipids reflected that of the diet fed. In experiment I, there was a definite but significantly lower incidence (P<0.01)
and severity (P<0.01) of heart lesions in rats fed control oils (corn, olive, soybean) than in rats fed rapeseed oils. Also,
in experiment II, a definite but lower incidence and severity of heart lesions occurred in rats fed control oils (soybean,
olive) compared to rats fed Tower RSO or this oil with added free 22∶1. Adding 22∶1 to an oil naturally high in 18∶3 (soybean)
did not alter the incidence of heart lesions, whereas adding 22∶1 to an oil naturally high in 18∶1 (olive) increased significantly
(P<0.01) both the incidence and severity of heart lesions. Thus, it appears that the background incidence of heart lesions
that are found in the rat in any case, and which are increased by rapeseed oil feeding, is caused by the imbalanced fatty
acid composition of the oil for the growing rat, i.e. high monoenes (18∶1, 20∶1, and 22∶1) and high 18∶3 and is not only due
to the presence of excess 18∶3.
Contribution No. 706, Animal Research Institute. 相似文献
10.
Karolina Brkić Bubola Olivera Koprivnjak Barbara Sladonja Dubravka Škevin Ivana Belobrajić 《European Journal of Lipid Science and Technology》2012,114(12):1400-1408
The aim of this investigation was to determine the impact of fruit ripening on chemical and sensorial changes in monovarietal olive oils obtained from two important olive cultivars grown in Croatia, Bu?a and ?rna. In Bu?a oils peroxide value, K232 and K270 increased during ripening, while no differences among three ripening stages in ?rna oils were observed. Oils of both cultivars at the later ripening stages had higher free acidity level and lower sensory score followed by mild loss in almost all positive sensory characteristics. Total phenols and antioxidant capacity decreased in Bu?a oils during fruit ripening, while in ?rna oils reached maximum level in purple stage and then progressively decreased in the black ripening stage. Oleic acid level slightly increased during ripening in both cultivar oils. Linoleic acid decreased in Bu?a oils obtained from black fruits while palmitic acid decreased in ?rna oils during ripening. In both monovarietal oils chlorophyll and carotenoids concentrations decreased during ripening. The two cultivars had different course of total aldehydes, total esters and total ketones during ripening, while total alcohols were the highest in oils from purple ripening stage and then decreased as ripening progress. Practical applications: During the ripening, the chemical composition of olive fruit changes influencing the quality grade, oxidative stability, sensory characteristics and nutritional value of the obtained products. The cultivars characterized by a similar trend of ripening process could have different course of chemical and sensorial changes in oil during fruit ripening. Therefore, knowledge about these changes is important for determination of proper harvest time of single cultivar to achieve optimum of its potential regarding desirable characteristics of obtained oil. 相似文献
11.
Frying Quality Characteristics of French Fries Prepared in Refined Olive Oil and Palm Olein 总被引:2,自引:0,他引:2
Elham Tabee Margaretha Jägerstad Paresh C. Dutta 《Journal of the American Oil Chemists' Society》2009,86(9):885-893
The objective of this study was to compare two oils with different polyunsaturated/saturated (P/S) fatty acid ratios, refined
olive oil (P/S 0.75) and palm olein (P/S 0.25), in frying French fries. The chemical qualities of the oil residues extracted
from the French fries were assayed for five consecutive batches fried at 1-h intervals. The levels of total polar compounds,
free fatty acids, p-anisidine value and phytosterol oxidation products (POPs) were elevated in French fries fried in both oils. The level of total
polar compounds increased from 4.6 in fresh refined olive oil to 7.3% in final batches of French fries. The corresponding
figures for palm olein were 9.8–13.8%. The level of free fatty acid in fresh refined olive oil increased from 0.06 to 0.11%
in final products. These figures for palm olein were 0.04–0.13%. The p-anisidine value increased from 3.7 to 32.8 and 2.5 to 53.4 in fresh oils and in final batches of French fries in refined
olive oil and palm olein, respectively. The total amount of POPs in fresh refined olive oil increased from 5.1 to 9.6 μg/g
oil in final products. These figures were 1.9 to 5.3 μg/g oil for palm olein. 相似文献
12.
13.
Pınar Kadiroğlu Figen Korel Figen Tokatlı 《Journal of the American Oil Chemists' Society》2011,88(5):639-645
An electronic nose (e-nose), in combination with chemometrics, has been used to classify the cultivar, harvest year, and geographical
origin of economically important Turkish extra virgin olive oils. The aroma fingerprints of the eight different olive oil
samples [Memecik (M), Erkence (E), Gemlik (G), Ayvalık (A), Domat (D), Nizip (N), Gemlik–Edremit (GE), Ayvalık–Edremit (AE)]
were obtained using an e-nose consisting a surface acoustic wave detector. Data were analyzed by principal component analysis
(PCA) and discriminant function analysis (DFA). Classification of cultivars using PCA revealed that A class model was correctly
discriminated from N in two harvest years. The DFA classified 100 and 97% of the samples correctly according to the cultivar
in the 1st and 2nd harvest years, respectively. Successful separation among the harvest years and geographical origins were
obtained. Sensory analyses were performed for determining the differences in the geographical origin of the olive oils and
the preferences of the panelists. The panelists could not detect the differences among olive oils from two different regions.
The cultivar, harvest year, and geographical origin of extra virgin olive oils could be discriminated successfully by the
e-nose. 相似文献
14.
Fatty Acid Profiling of the Main Tissues of Spanish Olive Fruit: Effect of the Oil Extraction Method
S. Gómez-González J. Ruiz-Jiménez M. D. Luque de Castro 《Journal of the American Oil Chemists' Society》2010,87(12):1413-1423
The aims of the present study were as follows: (1) study of the extraction efficiency of the methods to obtain extra virgin
olive oil and pomace oil, and the fatty oil composition provided by each tissue and the whole fruit using both methods; (2)
characterisation of the oil obtained by each extraction method according to quality parameters; and (3) development of chemometric
models able to explain the differences between the oils obtained from the different extraction procedures, olive varieties
or fruit tissues. With these objectives in mind, eight fruit varieties (i.e. arbequina, frantoio, hojiblanca, lechín from
Sevilla, manzanilla, ocal, picual and picudo) from the same geographical area, harvested when the maturation was complete
and the fatty acids content was at a maximum, were used. Oils from the whole fruit and from each of its main tissues (i.e.
ectocarp, mesocarp, endocarp, and kernel) were sequentially extracted by the two methods based on principles similar to those
used in the oil industry: pressure + centrifugation for extra virgin oil extraction and organic solvents for pomace oil. The
oils thus obtained were weighed to know the oil richness of the fruit and that of each separate tissue, and also to determine
the efficiency of each extraction method. Then, the fatty acids were subject to derivatisation, individual separation of the
products by gas chromatography and identification–quantitation by tandem-mass-spectrometry. The results thus obtained (fatty-acid
profile of the oil from each tissue obtained with each oil-extraction method and from each olive-fruit variety) were subject
to statistical studies to fulfill the aims of the research. 相似文献
15.
Alfonso Ranalli Donato Marchegiani Stefania Contento Fabio Girardi Maria Paola Nicolosi Marco Desiderio Brullo 《European Journal of Lipid Science and Technology》2009,111(7):678-687
This research paper reports on the concentrations of oleuropein in fruits of seven Italian olive cultivars. These oleuropein levels, during fruit growth and maturation, were monitored by taking olive samples from the same olive trees grown in Middle Italy. A novel high‐resolution gas chromatography (HRGC) oleuropein quantification method and a new high‐performance liquid chromatography (HPLC) method were developed. The olive fruits showed high contents of oleuropein, which were greatly influenced by the olive cultivar (genetic store) factor. The stage of fruit growth and maturation was another factor strongly affecting the contents of iridoid oleuropein in olive drupes, whatever the olive cultivar considered. Green olives had much higher concentrations of this biofunctional glucoside, which decreased regularly during fruit growth and ripeness. No differences were observed between the two developed oleuropein quantification methods, which gave, for all the olive cultivars, average values of fruit oleuropein contents that were not statistically different. These two reliable repetitive methods, noticeably the HPLC one (which also showed a lower running time), could be used for routine determination of oleuropein in olive drupes. We observed that, in general, olive cultivars having high oleuropein concentrations in the fruits were also characterized by marked oleuropein contents in the leaves. 相似文献
16.
V. M. Kapoulas S. Passaloglou-Emmanouilidou 《Journal of the American Oil Chemists' Society》1981,58(6):694-697
Samples of virgin olive oil and refined seed oils, as well as mixtures of olive oil with 10 and 5% seed oils were fractionated
by column chromatography on silicic acid impregnated with ammoniacal silver nitrate. It was possible to isolate a characteristic
fraction enriched in polyunsaturated triglycerides. Its linoleic acid content in pure olive oil never exceeds 9.3%, whereas
in pure seed oils, it varies between 38.1 and 70.1%; in mixtures of olive oil with 10 and 5% of seed oils, the respective
values are 22.3–38.2% and 15.6–32.1%. The oleic-to-linoleic acid ratios of the same fraction are more than 7.6 (olive oil),
0.2–0.8 (seed oils), 1.1–2.0 (olive oil with 10% seed oils) and 1.4–3.6 (olive oil with 5% seed oils). These analytical values
may be used as a safe criterion for the eventual adulteration of olive oil with seed oils.
This work was taken in part from the doctoral dissertation of S. Passaloglou-Emmanouilidou. 相似文献
17.
Samia Dabbou Faten Brahmi Ameni Taamali Manel Issaoui Youssef Ouni Mohamed Braham Mokhtar Zarrouk Mohamed Hammami 《Journal of the American Oil Chemists' Society》2010,87(10):1199-1209
The effects of the contents of lipids, pigments, α-tocopherol and phenols were studied in relation to the antioxidant capacity
of five virgin olive oils obtained from five olive cultivars planted in Tunisia (Arbequina, Koroneiki, Leccino, Oueslati and
Chemchali). The antioxidant capacities were evaluated by two different radical scavenging activities: radical scavenging activity
by the DPPH assay (RSA-DPPH) and total antioxidant status by the ABTS test (TAA-ABTS). The highest contents of antioxidant
compounds (75.96, 10.34, 6.32, 15.39 and 241.52 mg kg−1 for oleic acid, O/L ratio, carotenes, chlorophylls and total phenols, respectively) were found for the Koroneiki cultivar
except for α-tocopherol and o-diphenols, which had the highest contents (369 and 160.7 mg kg−1, respectively) in the Leccino and Chemchali cultivars (cvs). Furthermore, the highest antioxidant capacity in virgin olive
oil was observed in the Koroneiki cultivar (0.24 mmol TE kg−1) followed by the Chemchali and Leccino cvs (0.22 and 0.13 mmol TE kg−1) for the TAA-ABTS test. However, the RSA-DPPH activity was higher for the Chemchali cultivar (19.9%) than for the Koroneiki
and Leccino cvs (18.4 and 13.5%, respectively). Correlation between these capacities and the oil composition revealed that
they were mainly influenced by the carotene content, followed by chlorophyll and phenolic contents where the ABTS test was
more pronounced. Then, the antioxidant capacity of the virgin olive oils was correlated with polar components and the lipid
profile which are important for its shelf life. 相似文献
18.
Use of high-resolution 13C nuclear magnetic resonance spectroscopy for the screening of virgin olive oils 总被引:2,自引:0,他引:2
Rosario Zamora Virginia Alba Francisco J. Hidalgo 《Journal of the American Oil Chemists' Society》2001,78(1):89-94
13C Nuclear magnetic resonance (NMR) spectra of 104 oil samples were obtained and analyzed in order to study the use of this
technique for routine screening of virgin olive oils. The oils studied included the following: virgin olive oils from different
cultivars and regions of Europe and north Africa, and refined olive, “lampante” olive, refined olive pomace, high-oleic sunflower,
hazelnut, sunflower, corn, soybean, rapeseed, grapeseed, and peanut oils, as well as mixtures of virgin olive oils from different
geographical origins and mixtures of 5–50% hazelnut oil in virgin olive oil. The analysis of the spectra allowed us to distinguish
among virgin olive oils, oils with a high content of oleic acid, and oils with a high content of linoleic acid, by using stepwise
discriminant analysis. This parametric method gave 97.1% correct validated classifications for the oils. In addition, it classified
correctly all the hazelnut oil samples and the mixtures of hazelnut oil in virgin olive oil assayed. All of these results
suggested that 13C NMR may be used satisfactorily for discriminating some specific groups of oils, but to obtain 100% correct classifications
for the different oils and mixtures, more information than that obtained from the direct spectra of the oils is needed. 相似文献
19.
Barbara Garcia Júlia Magalhães Giuseppe Fregapane María Desamparados Salvador Fátima Paiva‐Martins 《European Journal of Lipid Science and Technology》2012,114(9):1070-1082
The effect of cultivar and ripeness stage on the potential nutritional value of monovarietal extra virgin olive oils (MEVOOs) obtained from Cordovil, Carrasquinha, Verdeal, and Negrinha do Freixo cultivars was investigated. MEVOOs produced were characterized by high oleic acid (72–83%), tocopherol (182–530 mg/kg), and phenolic compounds (326–1110 mg/kg) content and by a similar polyphenolic profile. 1‐Penten‐3‐one was found to be the compound with the highest contribution for the aroma of the four MEVOO, related to bitter, pungent, and leaf attributes. MEVOO from Verdeal cultivar showed the best performance in terms of the composition: the highest yield of oil, the highest content of oleic acid, high tocopherol, polyphenol and sterol content, and the lowest content of linoleic acid. These characteristics give to these MEVOO not only a great oxidative stability but also interesting properties from the health point of view. MEVOO obtained with fruits at the maturity index of around 4 were in general richer in beneficial minor compounds. MEVOO produced were discriminated by variety and ripeness stage, using a stepwise linear discriminant analysis. This discrimination will in the future enable the prevention of adulteration of these monovarietal olive oils with specific nutritional composition with other olive oils. Practical implications: High‐quality MEVOOs have recently been introduced in the market, which for growers is a practical way to differentiate and increase the commercial value of extra virgin olive oil. The quantification of major and minor olive oil compounds in monovarietal olive oils represents an objective way of predicting the sensory characteristics, stability, and potential health benefits of the oils, as well as preventing their adulteration with other olive oils. This study will help in the selection of olive varieties during the maintenance or development of new olive orchards and also to select optimum harvest period for these varieties, in order to obtain MEVOOs with the maximum quality and health benefits for consumers. 相似文献
20.
Olives were collected from various districts of Turkey (North and South Aegean sub-region, Bursa-Akhisar, South East Anatolia
region) harvested over seven (2001–2007) seasons. The aim of this study was to characterize the chemical profiles of the oils
derived from single variety Turkish olives including Ayvalik, Memecik, Gemlik, Erkence, Nizip Yaglik and Uslu. The olive oils
were extracted by super press and three phase centrifugation from early harvest olives. Chosen quality indices included free
fatty acid content (FFA), peroxide value (PV) and spectrophotometric characteristics in the ultraviolet (UV) region. According
to the FFA results, 46% (11 out of 24 samples) were classified as extra virgin olive oils; whereas using the results of PV
and UV, over 83% (over 19 of the 24 samples) had the extra virgin olive oil classification. Other measured parameters included
oil stability (oxidative stability, chlorophyll pigment, pheophytin-α), cis–trans fatty acid composition and color index. Oxidative stability among oils differed whereas the cis–trans fatty acid values were within the national and international averages. Through the application of two multivariate statistical
methods, Principal component and hierarchical analyses, early harvest virgin olive oil samples were classified according to
the geographical locations categorized in terms of fatty acid profiles. Such statistical clustering gave rise to defined groups.
These data provide evidence of the variation in virgin olive oil quality, especially early harvest and cis–trans isomers of fatty acid profiles from the diverse agronomic conditions in the olive growing regions of Turkey. 相似文献