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Olive Oil (olive + oil)
Kinds of Olive Oil Terms modified by Olive Oil Selected AbstractsBIOACTIVE POLAR LIPIDS IN OLIVE OIL, POMACE AND WASTE BYPRODUCTSJOURNAL OF FOOD BIOCHEMISTRY, Issue 4 2008HARALABOS C. KARANTONIS ABSTRACT Olive oil protects against atherosclerosis because of biologically active microconstituents. In this study, total polar lipids from olive oil, pomace, pomace oil and waste byproducts were extracted, fractionated by thin layer chromatography and tested for their bioactivity. The most active ones were further purified on high-performance liquid chromatography, and the resulting lipid fractions were tested for their bioactivity. Bioactive compounds were determined in all samples with the exception of olive pomace oil. These lipids inhibited platelet-activating factor (PAF)-induced platelet aggregation and also induced platelet aggregation. The bioactive compound from olive pomace has been chemically characterized as a glycerylether-sn-2-acetyl glycolipid based on mass spectra. Chemical determinations and mass spectrometry data reinforce the assumption that these active microconstituents share both similar bioactivity and common structural features. The existence of PAF antagonists in polar lipid extracts from olive oil waste by-products render them biologically valuable materials for the food industry that could be used for the production of functional foods. PRACTICAL APPLICATIONS Isolated bioactive polar lipids from waste by-products of the olive oil industry that act as inhibitors of platelet-activating factor (PAF) may be used for enrichment and production of foods with higher nutritional value, as PAF plays a major role in inflammatory disorders, including atherosclerosis development. [source] LOCATION EFFECTS ON OXIDATIVE STABILITY OF CHÉTOUI VIRGIN OLIVE OILJOURNAL OF FOOD BIOCHEMISTRY, Issue 6 2006SONIA BEN TEMIME ABSTRACT The effect of growing area on the natural antioxidant and oxidative stability of Chétoui virgin olive oil was studied. Total phenolic content, tocopherol composition, fatty acid composition and oxidative stability were analyzed. The results obtained in this study showed that Chétoui virgin olive oil composition is greatly influenced by growing environment, i.e., mainly by the climatic and pedologic factors. The cumulative rainfall appears to have a major influence on phenolic and o -diphenol content. Among studied samples, Amdoun oil had the highest total phenolic content, which exceeded 700 mg/kg. Moreover, it contained the highest amounts of o -diphenols 286.08 ± 6.74 mg/kg and total tocopherols 405.65 ± 4.17 mg/kg. The amounts of total phenols and o -diphenols showed a good correlation (P , 0.001) with stability while tocopherols showed a very low relation to oxidative stability. [source] EFFECT OF OLIVE OIL AND GLYCEROL ON PHYSICAL PROPERTIES OF WHEY PROTEIN CONCENTRATE FILMSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2008MAJID JAVANMARD ABSTRACT Olive oil was incorporated into whey protein through emulsification to produce films. Whey protein films were prepared by dispersing 10% protein in distilled water; and plasticized with different levels of glycerol (glycerol : protein [Gly : pro ] = 0.5 and 0.6). Olive oil was added at different levels (oil : pro = 0.0, 0.2, 0.3 and 0.4). The emulsion films were evaluated for mechanical properties, water vapor permeability (WVP) and opacity. Increasing the levels of Gly or olive oil in the films led to decreases in modulus and tensile strength. Increasing Gly content of films at oil/pro ratios of 0.2, 0.4 led to slight increases in elongation (EL). Increasing the oil : pro ratio further resulted in a decrease in EL for all films. No significant difference in WVP and opacity was observed between films made from mixtures of various proportions of whey protein concentrate,Gly with increasing olive oil (addition) at all levels of the plasticizer. PRACTICAL APPLICATIONS The main advantages of using edible films are extending food shelf life, improving food quality, adding value to the edible film-forming polymer and reducing synthetic packaging materials. Whey, obtained as a by-product in cheese, is produced in large quantities and has excellent functional properties and could potentially be used for edible films. [source] EFFECT OF STORAGE PERIOD AND EXPOSURE CONDITIONS ON THE QUALITY OF BOSANA EXTRA-VIRGIN OLIVE OILJOURNAL OF FOOD QUALITY, Issue 2 2006VINCENZO VACCA ABSTRACT Changes in quality parameters, antioxidant compounds, oxidative stability and antioxidant activity during 18 months of storage of a monovarietal extra-virgin olive oil from Bosana cultivar, and exposed to light and dark, were studied. Analysis of data showed that all the parameters underwent significant changes during storage: free acidity, peroxide and ultraviolet (UV) spectrophotometric indexes remained below the limits reported in the EEC Regulations 2568/91 and 1989/03, and these are: ,0.8% for acidity, ,20 meq O2/kg for peroxide and ,2.50 and ,0.22 for K232 and K270, respectively. Phenol and, -tocopherol content decreased during storage (42.0 and 29.6%, respectively) while chlorophylls and carotenoids underwent a decrease until 8 months of storage (49% and 30%, respectively); after that, the values remained constant. Oxidative stability and antioxidant activity had not changed dramatically during 18 months. Phenols were significantly correlated to the antioxidant activity of the oil, while oxidative stability measured by Rancimat did not show any correlation with carotenoids, chlorophylls, phenols and, -tocopherol. Regarding exposure conditions, storage in the dark was better in retaining the quality of the oil, as expected. [source] PHENOLIC COMPOUNDS, TOCOPHEROLS AND OTHER MINOR COMPONENTS IN VIRGIN OLIVE OILS OF SOME TUNISIAN VARIETIESJOURNAL OF FOOD BIOCHEMISTRY, Issue 2 2007D. KRICHENE ABSTRACT The phenols, ,-tocopherols, fatty acids and oxidative stability of six monovarietal virgin olive oils (VOOs) were determined. Fourteen phenolic compounds were detected and quantified by solid phase extraction and reversed phase-high performance liquid chromatography. Dialdehydic form of elenolic acid linked to tyrosol and hydroxytyrosol, oleuropein and ligstroside aglycones were the main components in all samples. Pinoresinol was the most abundant component in lignan fraction. The total phenol content of these monovarietal oils varied from 66.82 mg/kg in "Neb Jmel" oil to 662.74 mg/kg in "El Hor" oil. A wide range of ,-tocopherol contents was also noticed; it varied from 141.94 mg/kg in "Semni" variety to 364.23 mg/kg in "Jdallou" variety. With regard to pigments, chlorophylls and carotenoids were found at variable concentrations: with median values of 11.33 and 3.10 mg/kg, respectively. Among the studied varieties, "Oueslati" and El Hor were characterized by the lowest levels of palmitic and linoleic acids and the highest values of oleic acid. [source] PRELIMINARY EVALUATION OF THE APPLICATION OF THE FTIR SPECTROSCOPY TO CONTROL THE GEOGRAPHIC ORIGIN AND QUALITY OF VIRGIN OLIVE OILSJOURNAL OF FOOD QUALITY, Issue 4 2007ALESSANDRA BENDINI ABSTRACT A rapid Fourier transform infrared (FTIR) attenuated total reflectance spectroscopic method was applied to determine qualitative parameters such as free fatty acid (FFA) content and the peroxide value (POV) in virgin olive oils. Calibration models were constructed using partial least squares regression on a large number of virgin olive oil samples. The best results (R2 = 0.955, root mean square error in cross validation [RMSECV] = 0.15) to evaluate FFA content expressed in oleic acid % (w/w) were obtained considering a calibration range from 0.2 to 9.2% of FFA relative to 190 samples. For POV determination, the result obtained, built on 80 olive oil samples with a calibration range from 11.1 to 49.7 meq O2/kg of oil, was not satisfactory (R2 = 0.855, RMSECV = 3.96). We also investigated the capability of FTIR spectroscopy, in combination with multivariate analysis, to distinguish virgin olive oils based on geographic origin. The spectra of 84 monovarietal virgin olive oil samples from eight Italian regions were collected and elaborated by principal component analysis (PCA), considering the fingerprint region. The results were satisfactory and could successfully discriminate the majority of samples coming from the Emilia Romagna, Sardinian and Sicilian regions. Moreover, the explained variance from this PCA was higher than 96%. PRACTICAL APPLICATIONS The verification of the declared origin or the determination of the origin of an unidentified virgin olive oil is a challenging problem. In this work, we have studied the applicability of Fourier transform infrared coupled with multivariate statistical analysis to discriminate the geographic origin of virgin olive oil samples from different Italian regions. [source] COMPARISON OF THE VIRGIN OLIVE OILS PRODUCED IN DIFFERENT REGIONS OF TURKEYJOURNAL OF SENSORY STUDIES, Issue 3 2009MUSTAFA Ö ABSTRACT Virgin olive oils from different regions of Turkey were collected and analyzed. The total phenolics and antioxidant capacity of the samples ranged from 30.26 to 208.61 mg gallic acid/kg and 0.60 to 5.61 Trolox equivalents/kg, respectively. Free acidity (0.44,7.31% oleic acid), peroxide value (6.83,39.60 meq O2/kg), total volatiles (0.11,0.37%), viscosity (65.50,85.40 cP), K232 value (1.30,2.54), K270 value (0.08,0.30), refractive index (1.470) and descriptive sensory properties of the samples were also measured. The multidimensional scaling (MDS) analysis indicated that positive and negative attributes classification of the olive oil sensory defining terms were mostly the case, and total phenolics content by itself may be a useful classification index. Also, MDS maps showed that the samples from Southeastern and Aegean regions are closer, while others are separate from each other. PRACTICAL APPLICATIONS Data for the physicochemical and sensory descriptive properties of virgin olive oils from Turkey are provided for the scientific community, olive oil consumers and traders. Also, utilization of sensory data by multidimensional scaling technique for geographical origin groupings provides a unique insight for researchers for similar objectives. In addition, some findings (i.e., the eligibility of phenolics content by itself for olive oil classification) of this article produce new results for fast and practical application purposes yet confirmed by other researchers. [source] DNA Extraction from Olive Oil and PCR Amplification of Microsatellite MarkersJOURNAL OF FOOD SCIENCE, Issue 1 2005Raffaele Testolin And ABSTRACT: DNA was extracted from single-cultivar of cold-pressed (virgin) unfiltered and cotton-filtered olive oils that were stored at 4 °C for up to a year using different DNA extraction kits and protocols. DNA was amplified using original and nested primers designed on 6 microsatellites loci of the UDO series. The most consistent results in terms of successful single sequence repeat amplifications were achieved using the Qiagen QIAamp DNA stool extraction kit, slightly modified and applied to oil sample amounts as small as 200 ,L without any pretreatment. The kit allowed getting polymerase chain reaction (PCR) amplicons visible on gel and scorable peaks at the automatic sequencer for all 6 markers analyzed. Less consistent results were achieved with other kits, such as the Promega Wizard Magnetic DNA Purification System for Food, the LB Link-Biotech ExtMan 50,100 Evolution, the Qiagen Plant Mini kit, and the standard cetyltrimethyl-ammonium bromide-based DNA extraction protocol. The integration in the protocols of further tools, such as the hexane-based phase separation, the addition of water or NaCl solutions to the oil, the precipitation and the use of the pellet, and others, did not result in any substantial use. PCR amplifications that gave low DNA yields were improved by adopting the nested PCR technique, which uses the product of the 1st PCR as a template for a 2nd PCR carried out by means of internal primers. Conclusions are drawn as to the applicability of the method to trace the identity of single-cultivar virgin olive oils. Further work is required to check the sensitivity of the method in determining the varietal composition of blended oils, especially in detecting alleles from cultivars present in only small amounts. [source] Components of Olive Oil and Chemoprevention of Colorectal CancerNUTRITION REVIEWS, Issue 11 2005Yumi Z.H.Y. Hashim Olive oil contains a vast range of substances such as monounsaturated free fatty acids (e.g., oleic acid), hydrocarbon squalene, tocopherols, aroma components, and phenolic compounds. Higher consumption of olive oil is considered the hallmark of the traditional Mediterranean diet, which has been associated with low incidence and prevalence of cancer, including colorectal cancer. The anticancer properties of olive oil have been attributed to its high levels of monounsaturated fatty acids, squalene, tocopherols, and phenolic compounds. Nevertheless, there is a growing interest in studying the role of olive oil phenolics in carcinogenesis. This review aims to provide an overview of the relationship between olive oil phenolics and colorectal cancer, in particular summarizing the epidemiologic, in vitro, cellular, and animal studies on antioxidant and anticarcinogenic effects of olive oil phenolics. [source] Olive Oil as a Functional Food: Epidemiology and Nutritional ApproachesNUTRITION REVIEWS, Issue 6 2002Aliza H. Stark Ph.D. Olive oil is an integral ingredient of the Mediterranean diet and accumulating evidence suggests that it may have health benefits that include reduction of risk factors of coronary heart disease, prevention of several varieties of cancers, and modification of immune and inflammatory responses. Olive oil appears to be an example of a functional food, with varied components that may contribute to its overall therapeutic characteristics. Olive oil is known for its high levels of monounsaturated fatty acids and is also a good source of phytochemicals including polyphenolic compounds, squalene, and ,-tocopherol. [source] Nonisothermal Bioreactors in the Treatment of Vegetation Waters from Olive Oil: Laccase versus Syringic Acid as Bioremediation ModelBIOTECHNOLOGY PROGRESS, Issue 3 2005Angelina Attanasio Laccase from Trametes versicolor was immobilized by diazotization on a nylon membrane grafted with glycidil methacrylate, using phenylenediamine as spacer and coupling agent. The behavior of these enzyme derivatives was studied under isothermal and nonisothermal conditions by using syringic acid as substrate, in view of the employment of these membranes in processes of detoxification of vegetation waters from olive oil mills. The pH and temperature dependence of catalytic activity under isothermal conditions has shown that these membranes can be usefully employed under extreme pH and temperatures. When employed under nonisothermal conditions, the membranes exhibited an increase of catalytic activity linearly proportional to the applied transmembrane temperature difference. Percentage activity increases ranging from 62% to 18% were found in the range of syringic acid concentration from 0.02 to 0.8 mM, when a difference of 1°C was applied across the catalytic membrane. Because the percentage activity increase is strictly related to the reduction of the production times, the technology of nonisothermal bioreactors has been demonstrated to be an useful tool also in the treatment of vegetation waters from olive oil mills. [source] BIOACTIVE POLAR LIPIDS IN OLIVE OIL, POMACE AND WASTE BYPRODUCTSJOURNAL OF FOOD BIOCHEMISTRY, Issue 4 2008HARALABOS C. KARANTONIS ABSTRACT Olive oil protects against atherosclerosis because of biologically active microconstituents. In this study, total polar lipids from olive oil, pomace, pomace oil and waste byproducts were extracted, fractionated by thin layer chromatography and tested for their bioactivity. The most active ones were further purified on high-performance liquid chromatography, and the resulting lipid fractions were tested for their bioactivity. Bioactive compounds were determined in all samples with the exception of olive pomace oil. These lipids inhibited platelet-activating factor (PAF)-induced platelet aggregation and also induced platelet aggregation. The bioactive compound from olive pomace has been chemically characterized as a glycerylether-sn-2-acetyl glycolipid based on mass spectra. Chemical determinations and mass spectrometry data reinforce the assumption that these active microconstituents share both similar bioactivity and common structural features. The existence of PAF antagonists in polar lipid extracts from olive oil waste by-products render them biologically valuable materials for the food industry that could be used for the production of functional foods. PRACTICAL APPLICATIONS Isolated bioactive polar lipids from waste by-products of the olive oil industry that act as inhibitors of platelet-activating factor (PAF) may be used for enrichment and production of foods with higher nutritional value, as PAF plays a major role in inflammatory disorders, including atherosclerosis development. [source] EFFECT OF OLIVE OIL AND GLYCEROL ON PHYSICAL PROPERTIES OF WHEY PROTEIN CONCENTRATE FILMSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2008MAJID JAVANMARD ABSTRACT Olive oil was incorporated into whey protein through emulsification to produce films. Whey protein films were prepared by dispersing 10% protein in distilled water; and plasticized with different levels of glycerol (glycerol : protein [Gly : pro ] = 0.5 and 0.6). Olive oil was added at different levels (oil : pro = 0.0, 0.2, 0.3 and 0.4). The emulsion films were evaluated for mechanical properties, water vapor permeability (WVP) and opacity. Increasing the levels of Gly or olive oil in the films led to decreases in modulus and tensile strength. Increasing Gly content of films at oil/pro ratios of 0.2, 0.4 led to slight increases in elongation (EL). Increasing the oil : pro ratio further resulted in a decrease in EL for all films. No significant difference in WVP and opacity was observed between films made from mixtures of various proportions of whey protein concentrate,Gly with increasing olive oil (addition) at all levels of the plasticizer. PRACTICAL APPLICATIONS The main advantages of using edible films are extending food shelf life, improving food quality, adding value to the edible film-forming polymer and reducing synthetic packaging materials. Whey, obtained as a by-product in cheese, is produced in large quantities and has excellent functional properties and could potentially be used for edible films. [source] Antioxidant and other biological activities of phenols from olives and olive oilMEDICINAL RESEARCH REVIEWS, Issue 1 2002Francesco Visioli Abstract Olive oil is the principal source of fats in the Mediterranean diet, which has been associated with a lower incidence of coronary heart disease and certain cancers. Phenolic compounds, e.g., hydroxytyrosol and oleuropein, in extra-virgin olive oil are responsible for its peculiar pungent taste and for its high stability. Recent findings demonstrate that olive oil phenolics are powerful antioxidants, both in vitro and in vivo, and possess other potent biological activities that could partially account for the observed healthful effects of the Mediterranean diet. © 2001 John Wiley & Sons, Inc. Med Res Rev, 22, No. 1, 65,75, 2002 [source] Components of Olive Oil and Chemoprevention of Colorectal CancerNUTRITION REVIEWS, Issue 11 2005Yumi Z.H.Y. Hashim Olive oil contains a vast range of substances such as monounsaturated free fatty acids (e.g., oleic acid), hydrocarbon squalene, tocopherols, aroma components, and phenolic compounds. Higher consumption of olive oil is considered the hallmark of the traditional Mediterranean diet, which has been associated with low incidence and prevalence of cancer, including colorectal cancer. The anticancer properties of olive oil have been attributed to its high levels of monounsaturated fatty acids, squalene, tocopherols, and phenolic compounds. Nevertheless, there is a growing interest in studying the role of olive oil phenolics in carcinogenesis. This review aims to provide an overview of the relationship between olive oil phenolics and colorectal cancer, in particular summarizing the epidemiologic, in vitro, cellular, and animal studies on antioxidant and anticarcinogenic effects of olive oil phenolics. [source] Olive Oil as a Functional Food: Epidemiology and Nutritional ApproachesNUTRITION REVIEWS, Issue 6 2002Aliza H. Stark Ph.D. Olive oil is an integral ingredient of the Mediterranean diet and accumulating evidence suggests that it may have health benefits that include reduction of risk factors of coronary heart disease, prevention of several varieties of cancers, and modification of immune and inflammatory responses. Olive oil appears to be an example of a functional food, with varied components that may contribute to its overall therapeutic characteristics. Olive oil is known for its high levels of monounsaturated fatty acids and is also a good source of phytochemicals including polyphenolic compounds, squalene, and ,-tocopherol. [source] Olive oil production on bronze age Crete: nutritional properties, processing methods and storage life of Minoan olive oilOXFORD JOURNAL OF ARCHAEOLOGY, Issue 1 2002F.R. Riley Archaeological studies on olive oil produced in Crete in the Bronze Age focus primarily on aspects such as the period when olive cultivation became widespread, the number of olive trees cultivated, or the quantity of oil stored in the Minoan palaces. Olive oil is however an organic substance, a perishable product, the nutritional and storage properties of which are determined by environmental, agronomic, processing and storage conditions. In this paper archaeological, environmental and biochemical evidence is combined to present a comprehensive picture of the potential quality, nutritional and storage properties of Minoan olive oil. The comparative evidence presented suggests that Minoan olive oil was equal in quality to the cold-pressed virgin olive oils produced today, and as such, the oil was nutritionally important in the Bronze Age and a valuable trade commodity. [source] Morphological and immunohistochemical studies on cleft palates induced by 2,3,7,8-tetrachlorodibenzo- p -dioxin in miceCONGENITAL ANOMALIES, Issue 2 2008Kumiko Fujiwara ABSTRACT Morphological and immunohistological examinations were performed to reveal the mechanisms of cleft palate induction by 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD). ICR strain mice 8,10 weeks of age were used in the study. TCDD was administered in olive oil on gestation day (GD) 12.5 with gastric tubes at 40 ,g/kg. From GD 13.5 to 16.5, palates were examined by scanning electron microscopy (SEM), hematoxyline,eosin (HE) staining, and immunohistochemical staining of FGFR1/2, TGF-,3, MSX1 and LHX8. In the control group, both of the palatal shelves began elevating on GD 14.0 and finished within 6 h. After the elevation, all of the shelves had completely fused with each other on GD 14.5. In the TCDD-treated group, palatal shelves elevated 1 day later than in the control group. However, all palates had elevated by GD 15.0. After the elevation, the shelves contacted each other and fused; however, they were separated on GD16.0. HE staining showed that medial edge epithelium (MEE) was thinner in the TCDD group than in the control group. MEE observed under a high magnification (×2500) exhibited filopodia-like filaments and the cells were bulged in the control group. In contrast, in the TCDD group, no filaments were observed and the cells were flat with unclear boundaries. Immunohistologically, there were no characteristic findings except for FGFR1. FGFR1 was not expressed in the TCDD group after the fusion phase (GD 14.5). TCDD induces many morphological and molecular changes to MEE cells and causes cleft palates. [source] Occupational allergic contact dermatitis from olive oil in pizza makingCONTACT DERMATITIS, Issue 2 2004G. A. E. Wong No abstract is available for this article. [source] CE- and HPLC-TOF-MS for the characterization of phenolic compounds in olive oilELECTROPHORESIS, Issue 5 2007Alegría Carrasco-Pancorbo Abstract We present an easy and rapid method for the analysis of phenolic compounds in extra-virgin olive oil by CZE coupled with ESI-TOF-MS. Optimum electrophoretic separation was obtained using a basic carbonate electrolyte. We thus achieved the determination of several important families (phenyl alcohols, phenyl acids, lignans, flavonoids, and secoiridoids) of the polar fraction of the olive oil. Furthermore, other "unknown" compounds were also identified. In addition to the CZE method, HPLC analyses were made, separating compounds belonging to the main families present in this polyphenolic fraction, as well as other new compounds. We compared the results obtained with both techniques and found it was possible to determine more than 45 compounds with both methods. The sensitivity, together with mass accuracy and true isotopic pattern of the TOF-MS, allowed the identification of a broad series of known and so far not described phenolic compounds present in extra-virgin olive oil. [source] International conference on the healthy effect of virgin olive oilEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 7 2005Summary 1Ageing represents a great concern in developed countries because the number of people involved and the pathologies related with it, like atherosclerosis, morbus Parkinson, Alzheime's disease, vascular dementia, cognitive decline, diabetes and cancer. 2Epidemiological studies suggest that a Mediterranean diet (which is rich in virgin olive oil) decreases the risk of cardiovascular disease. 3The Mediterranean diet, rich in virgin olive oil, improves the major risk factors for cardiovascular disease, such as the lipoprotein profile, blood pressure, glucose metabolism and antithrombotic profile. Endothelial function, inflammation and oxidative stress are also positively modulated. Some of these effects are attributed to minor components of virgin olive oil. Therefore, the definition of the Mediterranean diet should include virgin olive oil. 4Different observational studies conducted in humans have shown that the intake of monounsaturated fat may be protective against age-related cognitive decline and Alzheimer's disease. 5Microconstituents from virgin olive oil are bioavailable in humans and have shown antioxidant properties and capacity to improve endothelial function. Furthermore they are also able to modify the haemostasis, showing antithrombotic properties. 6In countries where the populations fulfilled a typical Mediterranean diet, such as Spain, Greece and Italy, where virgin olive oil is the principal source of fat, cancer incidence rates are lower than in northern European countries. 7The protective effect of virgin olive oil can be most important in the first decades of life, which suggests that the dietetic benefit of virgin olive oil intake should be initiated before puberty, and maintained through life. 8The more recent studies consistently support that the Mediterranean diet, based in virgin olive oil, is compatible with a healthier ageing and increased longevity. However, despite the significant advances of the recent years, the final proof about the specific mechanisms and contributing role of the different components of virgin olive oil to its beneficial effects requires further investigations. [source] Postprandial lipemic response to alpha-linolenic acid rich oil, butter, and olive oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 9 2010Julia Svensson Abstract Postprandial lipemia varies with composition of dietary fat due to partitioning of fatty acids between ,-oxidation, incorporation into TAG, and tissue lipids. Effects of alpha-linolenic acid (ALA) are poorly characterized. Lipase-catalyzed transesterification was used to produce a novel ALA-oil (35% ALA) from rapeseed and linseed oil. We hypothesized a lower postprandial lipemic response with ALA-oil than with olive oil and butter due to higher ,-oxidation of ALA. A randomized crossover study with 26 healthy men compared the effects on plasma lipids 7,h after a breakfast containing 35,g ALA-rich oil, butter fat, or olive oil. The incremental area under curve for plasma TAG was lower with butter than with olive oil (34%, p<0.05) and ALA-oil (25%, ns). After ALA-oil percentage ALA increased, in TAG to a constant level of 7,mol% and in NEFA to 6% after 7,h. Since total NEFA increased with time the amount of exogenous ALA in NEFA also increased. Butter resulted in lower postprandial lipemia than the oils, the difference exceeding what is expected from the presence of short and medium chain fatty acids in butter. There was a considerable recirculation of ALA into the NEFA pool available for oxidation. Practical application: Enzymatic transesterification was used to produce a dietary oil rich in ALA. By randomizing the partitioning of ALA more evenly between the TAG molecules the risk of oxidation could be reduced. Analyses showed that the ALA-oil was stable during storage for at least 3 months. Enzymatic transesterification could be used as an advantageous method to design an ALA rich dietary oil with new properties regarding fatty acid composition, susceptibility to oxidation, and effects on blood lipids. [source] Effect of location on virgin olive oils of the two main Tunisian olive cultivarsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 9 2009Mokhtar Guerfel Abstract The olive oil content in phenolic compounds depends on the variety of the fruit used for its extraction as well as on the predominant climate conditions in the tree cultivation area. Here, we report on the characterization of virgin olive oil samples obtained from fruits of the main Tunisian olive cultivars Chemlali and Chétoui, grown in three different Tunisian locations, Zaghouan (North), Sousse (Center) and Sfax (South). Chétoui olive oil samples obtained from fruits of olive trees cultivated in Zaghouan and Chemlali olive oil samples obtained from fruits of olive trees cultivated in Sousse were found to have a higher mean total phenol content (1004 and 330,mg/kg, respectively). Olive oil samples obtained from fruits of both cultivars had different phenolic profiles and a higher content in 3,4-DHPEA-EDA when the olive trees were cultivated in Zaghouan. Both olive cultivars were found to have different responses to environmental conditions. Chétoui olive oil showed decreased oxidative stability when the fruits were obtained from olive trees cultivated in the center of Tunisia (34.8,h) and in Sfax (16.17,h). Furthermore, statistical data showed that the phenolic composition and oxidative stability of Chétoui olive oil varied more by location than those of Chemlali olive oils. [source] Enrichment of pomace olive oil in triterpenic acids during storage of "Alpeorujo" olive pasteEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 12 2008Aranzazu García Abstract Triterpenic acids are natural compounds present in plants and foods with beneficial properties for human health and thus they are desirable in the food, cosmetics and pharmaceutical industries. Pomace olive is considered a good source of these substances. In this study, oleanolic and maslinic acids were found to be the main triterpenic acids identified in pomace olive oil obtained from stored "Alpeorujo". Determination of the two acids was achieved by a new procedure that consists of extracting the acids from the oil with a mixture of methanol/ethanol, and then separating and quantifying them by HPLC. Results showed that their concentration increased up to 16,g/kg of oil during storage of the pomace in large ponds for 7,months. The concentration of both triterpenic acids was similar in the pomace olive oil obtained by using the centrifugation system. By contrast, a much lower concentration of maslinic than oleanolic acid was detected in pomace olive oils obtained by solvent extraction from the previously centrifugated "Alpeorujo" paste. These triterpenic acids also contributed to the acidity of the crude oil. Likewise, the oil of the pomace paste was enriched in other substances such as 4-ethylphenol and aliphatic alcohols during the storage of the paste in large ponds. Consequently, crude pomace olive oil can be considered a good source of triterpenic acids when obtained from a stored olive paste. [source] A simplified method for HPLC-MS analysis of sterols in vegetable oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 12 2008Antonio Segura Carretero Abstract We have developed a liquid-chromatographic method using atmospheric pressure chemical ionization (APCI)-mass spectrometry (MS) detection in positive mode. This method was used to separate and identify 15,sterols and 2,dihydroxy triterpenes in saponified oils, enabling the analysis of these compounds directly from saponified samples without recourse to thin-layer chromatography; this fact thus significantly simplifies the process. The analyses were made using a Waters Atlantis 5,µm dC18 150×2.1,mm column with a gradient of acetonitrile/water (0.01% acetic acid) at a flow rate of 0.5,mL/min and a column temperature of 30,°C. The quantification of several of these compounds in soybean oil, palm oil, seed oil, sunflower oil, olive-pomace oil and virgin olive oil was carried out using their commercial standards, and the results were compared satisfactorily with the official method. [source] Characterization and chemometric study of crude and refined oils from table olive by-productsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 6 2008M. Victoria Ruiz-Méndez Abstract Table olive processing produces defective fruits and the conditioning operations give rise to solid by-products which are processed to obtain oil. In this study, the most relevant characteristics of crude oils extracted from table olive by-products were high average acidity values (4.5%, green olives; 8.1%, ripe olives), ECN42 values of 0.34 (green olives) and 0.10 (ripe olives), while 2-mono-palmitin averaged 0.92%. The overall content of sterols was 2257,mg/kg (green olives) and 1746,mg/kg (ripe olives), while the concentration of cholesterol was 36,mg/kg (green olives) and 19,mg/kg (ripe olives). The effect of refining was mainly reflected by a decrease in acidity and sterols. Although most characteristics were in agreement with the established regulation for olive oil, the overall trans fatty acid content, the low apparent ,-sitosterol content, and the relatively high cholesterol content prevented their inclusion into classes of crude or refined lampante or pomace olive oils, not even into the vegetable oil category. Therefore, the oils analyzed should be considered for non-edible purposes. The physicochemical characteristics used for chemometric discrimination permitted discrimination among types of oils (crude, 100%; physically refined, 90%; chemically refined, 100%), elaboration styles (green and ripe olives, 100%) and cultivars (Gordal, Manzanilla, Hojiblanca and Cacereña, 100%), with the sterol composition being the most useful parameter for discrimination. [source] Endogenous microflora in turbid virgin olive oils and the physicochemical characteristics of these oilsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 2 2008Anastasios Koidis Abstract Cloudy olive oil, the fresh olive juice, is an intermediate form before full precipitation of freshly produced olive oil. Some consumers prefer it because they consider it as more natural and less processed. The cloudy form can persist for several months. The oil is a sort of dispersion/suspension system which can be also described as a micro-emulsion/suspension. Water micro-droplets were found to have a size ranging from 1 to 5,µm. Cloudiness is due to the low water content and the presence of natural emulsifiers in the oil. The suspension is formed by solid particles (5,60,µm) deriving from the olive fruit. They are present in small amounts (12,460,mg/kg oil). In the newly produced olive oil, containing 0.17,0.49% water, a number of microorganisms of different types (bacteria, yeasts, moulds) were found to survive, but at very low concentrations (<3,log,cfu/mL oil). They originate from the exterior of the fruit (epiphytic microflora) and their presence is considered natural. Their enzyme activities do not seem to affect the quality of the final product. [source] Formation and distribution of oxidized fatty acids during deep- and pan-frying of potatoesEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 11 2007Nick Kalogeropoulos Abstract The formation of cis- 9,10-epoxystearate, trans- 9,10-epoxystearate, cis -9,10-epoxyoleate, cis -12,13-epoxyoleate, trans -9,10-epoxyoleate, trans -12,13-epoxyoleate and the co-eluting 9- and 10-ketostearates during eight successive pan- and deep-frying sessions of pre-fried potatoes in five different types of vegetable oils , namely cottonseed oil, sunflower oil, vegetable shortening, palm oil and virgin olive oil , was followed and quantified both in fried oils and in fried potatoes by GC/MS after derivatization to methyl esters. These oxidized fatty acids were present at relatively low concentrations in the fresh oils and pre-fried potatoes while they increased linearly with frying time, reaching up to 1140.8,µg/g in virgin olive oil (VOO) and 186.9,µg/g in potatoes pan-fried in VOO after eight pan-frying sessions, with trans -9,10-epoxystearate predominating in all cases. The formation of polymerized triacylglycerols (PTG) was also quantified in frying oils by size exclusion HPLC. Pan-frying caused higher oxidized fatty acid and PTG formation compared to deep-frying. Epoxyoleates and PTG concentrations were increased after frying in polyunsaturated oils, while epoxystearate and 9- and 10-ketostearate concentrations were increased after frying in monounsaturated oils. No specific absorption of the oxidized fatty acids by the fried potatoes seems to occur. The dietary intake of oxidized fatty acids and PTG by the consumption of fried potatoes was discussed. [source] Automated ultrasound-assisted method for the determination of the oxidative stability of virgin olive oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 2 2007José Platero-López Abstract A fast and automated method is proposed for determining the oxidative stability of virgin olive oil by using ultrasound. The ultrasound microprobe (3,mm in diameter) was directly immersed into the olive oil sample contained in a test tube. The most influential variables in the oxidation process, namely pulse amplitude, duty cycle, irradiation time, and sample amount, were optimized. The oil absorbance at 270,nm was continuously monitored by oil recirculation through a 0.1-mm path length flow cell connected to a fiber optic microspectrometer. This short path length allowed the direct monitoring of absorbance without needing any sample dilution. The ultrasound energy was applied during 35,min, and the resulting increase in absorbance was continuously monitored. The difference between the final and the initial absorbance at 270,nm of a set of virgin olive oil samples was closely correlated with their oxidative stability calculated by the Rancimat method (R2,=,0.9915). The resulting equation enabled the prediction of the oxidative stability of virgin olive oil in a short period of time (35,min), by using a simple, inexpensive, automatic and easy-to-use system. [source] Dietary patterns and risk for Crohn's disease in childrenINFLAMMATORY BOWEL DISEASES, Issue 3 2008Savio D'Souza MBBS Abstract Background: Some dietary foods are considered protective (vegetables and fruits), whereas others (fatty foods) are thought to enhance the risk for Crohn's disease (CD). The evidence, however, is inconsistent. Methods: We postulated that specific dietary patterns may influence the risk for CD. A case-control study was carried out. Newly diagnosed CD cases with population and/or hospital-based controls ,20 years were selected from 3 tertiary hospitals across Canada. Predisease diet was assessed using a validated food frequency questionnaire (FFQ) administered within 1 month of diagnosis. Factor analyses and unconditional logistic regression (adjusted) was used to determine gender-specific dietary patterns and assess associated risks for CD. Odds ratios (ORs) and corresponding 95% confidence intervals (95% CIs) were estimated. Results: A total of 149 cases and 251 controls were included. The mean age (range) of the cases was 13.3 (2.6-20 years). There were more boys (61.1%). Four dietary patterns each were observed among both boys and girls. Pattern 1 in girls, characterized by meats, fatty foods, and desserts, was positively associated with CD (OR 4.7, 95% CI 1.6,14.2). Pattern 2, common to both boys and girls, was characterized by vegetables, fruits, olive oil, fish, grains, and nuts and was inversely associated with CD in both genders (girls: OR 0.3, 95% CI 0.1,0.9; boys: OR 0.2, 95% CI 0.1,0.5). Conclusions: Our results suggest that specific dietary patterns could be associated with higher or lower risks for CD in children. Larger prospective studies are required to confirm these findings. (Inflamm Bowel Dis 2007) [source] | |||||||||||||||||||||||||||||||||||||