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Ramón Aparicio - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of α-tocopherol in Virgin Olive Oil by a luminiscent method.
Grasas y Aceites, 2009Co-Authors: M. E. Escuderos, Maria T. Morales, Ana Sayago, Ramón AparicioAbstract:Natural fluorophores such as tocopherols are of great importance for the characterization and authentication of Virgin Olive Oil. The band of the luminescent spectrum which is most accurately associated with the presence of α- tocopherol (380-420 nm) at λ exc = 350 nm was detected and its precision was evaluated once the analytical process was optimized. A Virgin Olive Oil, cv. Cornicabra, was spiked with several quantities of α-tocopherol, from 25 mg/Kg to 1200mg/Kg, to build a ridge regression model (adjusted-R 2 = 0.99) based on five wavelengths (370, 371, 378, 414 and 417 nm) which are attributed to the fluorescence of this compound. The tentative model was validated (adjusted-R 2 = 0.87) with 8 samples of a Virgin Olive Oil, cv . Picual, spiked with amounts of -tocopherols ranging from 25 mg/kg to 250mg/kg. Finally, the model was successfully validated with 7 monovarietal Virgin Olive Oils from various Olive producing countries (adjusted - R 2 = 0.92).
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Characterization of Olive paste volatiles to predict the sensory quality of Virgin Olive Oil
European Journal of Lipid Science and Technology, 2007Co-Authors: Diego L. García-gonzález, Noelia Tena, Ramón AparicioAbstract:One of the main challenges that Virgin Olive Oil producers face today is an accurate prediction of the sensory quality of the final product prior to the milling of the Olives. The possibility that Olive paste aroma can be used as a predictive measurement of Virgin Olive Oil quality is studied in this paper. The study was centered on distinguishing the aroma of Olive pastes that produced Virgin Olive Oils without sensory defects from the aroma of Olive pastes the Virgin Olive Oils of which showed sensory defects. Olive pastes were analyzed by solid-phase microextraction-gas chromatography and a sensor system based on metal oxide sensors. Forty-four volatile compounds were identified in Olive pastes, all of them being also present in Virgin Olive Oil. Six volatile compounds - acetic acid, octane, methyl benzene, (E)-2-hexenal, hexyl acetate and 3-methyl-1-butanol - distinguished both kinds of pastes with only five misclassified samples. Five metal oxide sensors were able to classify the Olive pastes with only two erroneous classifications.
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Changes induced by UV radiation during Virgin Olive Oil storage.
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Guadalupe Luna, Maria T. Morales, Ramón AparicioAbstract:The effects of UV radiation on the chemical and sensory characteristics of Virgin Olive Oils (cv. Arbequina and Picual) were assessed. Even small doses of UV radiation induced oxidation of the Virgin Olive Oil samples. Total phenols and fatty acids contents decreased during the process as well as the intensity of the bitter and fruity sensory attributes, while the intensity of the rancid sensory attribute notably increased. Acetaldehyde, 2-butenal, 2-pentenal, octane, octanal, hexanal, nonanal, and 2-decenal were the volatile compounds most affected, showing an important increase during the irradiation process. Nonanal, hexanal, and pentanal showed high correlation with the rancid sensory attribute (90%, 86%, and 86%, respectively). 2-Decenal and nonanal concentrations allowed us to predict the alteration level of the samples by mean of multiple Ridge regression. Keywords: Virgin Olive Oil; UV radiation; oxidation; volatiles; off-flavors
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changes in the volatile composition of Virgin Olive Oil during oxidation flavors and off flavors
Journal of Agricultural and Food Chemistry, 1997Co-Authors: M. T. Morales, Jose Rios, Ramón AparicioAbstract:A thermoxidation process has been applied to extra-Virgin Olive Oil to develop new knowledge on the evolution of the volatile compounds responsible for Virgin Olive Oil flavor during oxidative deterioration. The initial volatiles (a total of 60), many of them responsible for the pleasant sensory characteristics of the Oil and produced mainly through biochemical pathways, disappeared in the first hours, and the formation of off-flavors, produced through oxidative pathways, gradually increased. The main volatile compounds possibly responsible for off-flavors (51) were identified, and their evolution during the oxidative process was studied. The fatty acids content was determined during the process. Unsaturated fatty acids were found to be the main precursors of the volatile compounds found in oxidized samples. The early measurement of nonanal (which was not detected at all, or only at trace levels, in extra-Virgin Olive Oil samples) could be an appropriate method to detect the beginning of the oxidation. Th...
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Detection of Virgin Olive Oil Adulteration by Fourier Transform Raman Spectroscopy
Journal of Agricultural and Food Chemistry, 1996Co-Authors: Vincent Baeten, M. T. Morales, Marc Meurens, Ramón AparicioAbstract:The authenticity of products labeled as Virgin Olive Oil is of great importance from commercial and health aspects. The combination of Fourier transform-Raman (FT-Raman) spectroscopy with multivariate procedures has been used for predicting the level of adulteration in a set of Virgin Olive Oil samples that were adulterated with soybean, corn, and raw Olive residue (Olive pomace) Oils at 1, 5, and 10%, respectively. Six genuine Virgin Olive Oil samples, differing in their chemical composition, were selected from a set of 1428 European samples. The best result in prediction of adulteration was an adjusted R(2) value of 0.964, determined by regression on principal components (PCR), giving 100% correct discrimination between genuine and adulterated samples and 91.3% correct classifications at different adulteration levels.
Constantinos A Georgiou - One of the best experts on this subject based on the ideXlab platform.
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Rapid synchronous fluorescence method for Virgin Olive Oil adulteration assessment
Food Chemistry, 2007Co-Authors: Konstantina I Poulli, George A Mousdis, Constantinos A GeorgiouAbstract:Abstract This paper describes the differentiation of Virgin Olive from Olive-pomace, corn, sunflower, soybean, rapeseed and walnut Oils using total synchronous fluorescence (TSyF) spectra. TSyF spectra are acquired by varying the excitation wavelength in the region 250–720 nm and the wavelength interval (Δλ) in the region from 20 to 120 nm. It is shown that adulterants can be discriminated from Virgin Olive Oil using a wavelength interval of 20 nm and excitation wavelength region 315–400, 315–392, 315–375, 315–365, 315–375 and 315–360 for Olive-pomace, corn, sunflower, soybean, rapeseed and walnut Oils, respectively. Thirty one Virgin Olive Oil mixtures with each potential adulterant were prepared at varying levels with emphasis at low concentrations. The partial least-squares regression model was used to quantify adulteration. This technique is useful for detection of Olive-pomace, corn, sunflower, soybean, rapeseed and walnut Oil in Virgin Olive Oil at levels of 2.6%, 3.8%, 4.3%, 4.2%, 3.6%, and 13.8% (w/w), respectively.
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synchronous fluorescence spectroscopy for quantitative determination of Virgin Olive Oil adulteration with sunflower Oil
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Konstantina I Poulli, George A Mousdis, Constantinos A GeorgiouAbstract:Adulteration of extra Virgin Olive Oil with sunflower Oil is a major issue for the Olive Oil industry. In this paper, the potential of total synchronous fluorescence (TSyF) spectra to differentiate Virgin Olive Oil from sunflower Oil and synchronous fluorescence (SyF) spectra combined with multivariate analysis to assess the adulteration of Virgin Olive Oil are demonstrated. TSyF spectra were acquired by varying the excitation wavelength in the region 270–720 nm and the wavelength interval (Δλ) in the region from 20 to 120 nm. TSyF contour plots for sunflower, in contrast to Virgin Olive Oil, show a fluorescence region in the excitation wavelength range 325–385 nm. Fifteen different Virgin Olive Oil samples were adulterated with sunflower Oil at varying levels (0.5–95%) resulting in one hundred and thirty six mixtures. The partial least-squares regression model was used for quantification of the adulteration using wavelength intervals of 20 and 80 nm. This technique is useful for detection of sunflower Oil in Virgin Olive Oil at levels down to 3.4% (w/v) in just two and a half minutes using an 80-nm wavelength interval.
Antonietta Baiano - One of the best experts on this subject based on the ideXlab platform.
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partial substitution of pork backfat with extra Virgin Olive Oil in salami products effects on chemical physical and sensorial quality
Meat Science, 2003Co-Authors: C Severini, Teresa De Pilli, Antonietta BaianoAbstract:The effects on chemical, physical and sensory quality of the partial substitution of pork backfat with extra-Virgin Olive Oil were studied in 'salami' products. Four 'salami' formulations, with 15% total fat, were prepared, in which 0, 33.5, 50 and 66.5% of pork backfat was substituted with extra-Virgin Olive Oil. The partial pork backfat substitution with extra-Virgin Olive Oil did not substantially affect the chemical, physical and sensorial characteristics of products, with the exception of water activity and texture. With regard to both oxidation and loss of organoleptic quality, the addition of extra-Virgin Olive Oil, rich in mono-unsaturated fatty acids, did not decrease the shelf-life. The difference between samples with and without extra-Virgin Olive Oil was a piquant note detected in the Oil-added 'salami'. The formulation with 5% Olive Oil, corresponding to 33.3% substitution of pork backfat with Olive Oil, was judged best of all formulations. The results show that it is possible to produce this type of product, of good taste, similar to the traditional one, but with healthier features.
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Partial substitution of pork backfat with extra-Virgin Olive Oil in ‘salami’ products: effects on chemical, physical and sensorial quality
Meat science, 2003Co-Authors: C Severini, Teresa De Pilli, Antonietta BaianoAbstract:The effects on chemical, physical and sensory quality of the partial substitution of pork backfat with extra-Virgin Olive Oil were studied in 'salami' products. Four 'salami' formulations, with 15% total fat, were prepared, in which 0, 33.5, 50 and 66.5% of pork backfat was substituted with extra-Virgin Olive Oil. The partial pork backfat substitution with extra-Virgin Olive Oil did not substantially affect the chemical, physical and sensorial characteristics of products, with the exception of water activity and texture. With regard to both oxidation and loss of organoleptic quality, the addition of extra-Virgin Olive Oil, rich in mono-unsaturated fatty acids, did not decrease the shelf-life. The difference between samples with and without extra-Virgin Olive Oil was a piquant note detected in the Oil-added 'salami'. The formulation with 5% Olive Oil, corresponding to 33.3% substitution of pork backfat with Olive Oil, was judged best of all formulations. The results show that it is possible to produce this type of product, of good taste, similar to the traditional one, but with healthier features.
Konstantina I Poulli - One of the best experts on this subject based on the ideXlab platform.
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Rapid synchronous fluorescence method for Virgin Olive Oil adulteration assessment
Food Chemistry, 2007Co-Authors: Konstantina I Poulli, George A Mousdis, Constantinos A GeorgiouAbstract:Abstract This paper describes the differentiation of Virgin Olive from Olive-pomace, corn, sunflower, soybean, rapeseed and walnut Oils using total synchronous fluorescence (TSyF) spectra. TSyF spectra are acquired by varying the excitation wavelength in the region 250–720 nm and the wavelength interval (Δλ) in the region from 20 to 120 nm. It is shown that adulterants can be discriminated from Virgin Olive Oil using a wavelength interval of 20 nm and excitation wavelength region 315–400, 315–392, 315–375, 315–365, 315–375 and 315–360 for Olive-pomace, corn, sunflower, soybean, rapeseed and walnut Oils, respectively. Thirty one Virgin Olive Oil mixtures with each potential adulterant were prepared at varying levels with emphasis at low concentrations. The partial least-squares regression model was used to quantify adulteration. This technique is useful for detection of Olive-pomace, corn, sunflower, soybean, rapeseed and walnut Oil in Virgin Olive Oil at levels of 2.6%, 3.8%, 4.3%, 4.2%, 3.6%, and 13.8% (w/w), respectively.
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synchronous fluorescence spectroscopy for quantitative determination of Virgin Olive Oil adulteration with sunflower Oil
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Konstantina I Poulli, George A Mousdis, Constantinos A GeorgiouAbstract:Adulteration of extra Virgin Olive Oil with sunflower Oil is a major issue for the Olive Oil industry. In this paper, the potential of total synchronous fluorescence (TSyF) spectra to differentiate Virgin Olive Oil from sunflower Oil and synchronous fluorescence (SyF) spectra combined with multivariate analysis to assess the adulteration of Virgin Olive Oil are demonstrated. TSyF spectra were acquired by varying the excitation wavelength in the region 270–720 nm and the wavelength interval (Δλ) in the region from 20 to 120 nm. TSyF contour plots for sunflower, in contrast to Virgin Olive Oil, show a fluorescence region in the excitation wavelength range 325–385 nm. Fifteen different Virgin Olive Oil samples were adulterated with sunflower Oil at varying levels (0.5–95%) resulting in one hundred and thirty six mixtures. The partial least-squares regression model was used for quantification of the adulteration using wavelength intervals of 20 and 80 nm. This technique is useful for detection of sunflower Oil in Virgin Olive Oil at levels down to 3.4% (w/v) in just two and a half minutes using an 80-nm wavelength interval.
R De La Torre - One of the best experts on this subject based on the ideXlab platform.
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Tyrosol and hydroxytyrosol are absorbed from moderate and sustained doses of Virgin Olive Oil in humans.
European journal of clinical nutrition, 2003Co-Authors: Elisabet Miro-casas, Montse Fito, María-isabel Covas, M Farré-albadalejo, J. Marrugat, R De La TorreAbstract:Objective: To investigate the absorption of tyrosol and hydroxytyrosol from moderate and sustained doses of Virgin Olive Oil consumption. The study also aimed to investigate whether these phenolic compounds could be used as biomarkers of Virgin Olive Oil intake. Design and interventions: Ingestion of a single dose of Virgin Olive Oil (50 ml). Thereafter, for a week, participants followed their usual diet which included 25 ml/day of the same Virgin Olive Oil as the source of raw fat. Setting: Unitat de Recerca en Farmacologia. Institut Municipal d'Investigacio Medica (IMIM). Subjects: Seven healthy volunteers. Results: An increase in 24 h urine of tyrosol and hydroxytyrosol, after both a single-dose ingestion (50 ml) and short-term consumption (one week, 25 ml/day) of Virgin Olive Oil (P
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tyrosol and hydroxytyrosol are absorbed from moderate and sustained doses of Virgin Olive Oil in humans
European Journal of Clinical Nutrition, 2003Co-Authors: Elisabe Mirocasas, Montse Fito, M Farrealbadalejo, J Marruga, María-isabel Covas, R De La TorreAbstract:Objective: To investigate the absorption of tyrosol and hydroxytyrosol from moderate and sustained doses of Virgin Olive Oil consumption. The study also aimed to investigate whether these phenolic compounds could be used as biomarkers of Virgin Olive Oil intake. Design and interventions: Ingestion of a single dose of Virgin Olive Oil (50 ml). Thereafter, for a week, participants followed their usual diet which included 25 ml/day of the same Virgin Olive Oil as the source of raw fat. Setting: Unitat de Recerca en Farmacologia. Institut Municipal d'Investigacio Medica (IMIM). Subjects: Seven healthy volunteers. Results: An increase in 24 h urine of tyrosol and hydroxytyrosol, after both a single-dose ingestion (50 ml) and short-term consumption (one week, 25 ml/day) of Virgin Olive Oil (P<0.05) was observed. Urinary recoveries for tyrosol were similar after a single dose and after sustained doses of Virgin Olive Oil. Mean recovery values for hydroxytyrosol after sustained doses were 1.5-fold those obtained after a single 50 ml dose. Conclusion: Tyrosol and hydroxytyrosol are absorbed from realistic doses of Virgin Olive Oil. With regard to the dose–effect relationship, 24 h urinary tyrosol seems to be a better biomarker of sustained and moderate doses of Virgin Olive Oil consumption than hydroxytyrosol. Sponsorship: This work was supported by grants ALI97-1607-CO2-01 from CICYT, 98/9562 FPI from FIS and by Federacio de Cooperatives Agraries de Catalunya.
