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Tocopherol Content (tocopherol + content)
Selected AbstractsEFFECTS OF PRESTORAGE DRY AND HUMID HOT AIR TREATMENTS ON THE QUALITY, TRIGLYCERIDES AND TOCOPHEROL CONTENTS IN ,HASS' AVOCADO FRUITJOURNAL OF FOOD QUALITY, Issue 2 2004J. DE JESUS ORNELAS P. ABSTRACT ,Hass' avocado fruit were heated with dry (50% RH) or moist (95% RH) forced air at 38Cfor 6 h and then stored at 5C and 85% RHfor up to 8 weeks. Fruit were evaluated weekly for quality and for the content of three triglycerides and three tocopherols. Heated fruit had higher weight loss. The nonheated fruit and those heated with dry air displayed the best external quality. Fruit heated with dry air exhibited the best internal quality and the lowest chilling injury incidence. The respiration rate was more intense in fruit heated with moist air. Fruit firmness immediately after harvest was 51N, but decreased to less than 20 N at the end of the storage period in the three treatments. The analysis of triglycerides and tocopherols showed that the 1,2-Dilinoleil-3-Oleil-Glycerol and ,-tocopherol were the most abundant compounds. Therefore, postharvest treatment with dry forced hot air before storage or transport reduces the incidence of chilling injury, and decreases quality deterioration in ,Hass' avocado fruit. [source] Volatiles and Oxidative Changes in Irradiated Pork Sausage with Different Fatty Acid Composition and Tocopherol ContentJOURNAL OF FOOD SCIENCE, Issue 2 2000C. Jo ABSTRACT: Aerobic-packaged sausage irradiated at 4.5 kGy had higher (P < 0.05) 2-thiobarbituric acid reactive substances (TBARS) than those irradiated at 0 or 2.5 kGy at 0-d storage. Generally, TBARS of aerobic- or vacuum-packaged sausage prepared with lard were higher (P < 0.05) than those of sausage prepared with flaxseed oil or corn oil. The amount of 1-heptene and 1-nonene increased (P < 0.05) with increased irradiation doses. Aldehydes, ketones, and alcohols were not influenced by irradiation at 0-d storage. However, irradiation accelerated lipid oxidation and increased the amount of aldehydes, ketones, and alcohols in aerobic-packaged sausage during storage. The tocopherol content in the sausage influenced (P < 0.05) production of volatiles at different levels of unsaturated fatty acids. [source] Influence of Vitamin E Source and Dietary Supplementation Level on Production Performance of Sunshine Bass, Morone chrysops , × Morone saxatilis ,, Fillet Tocopherol Content, and Immunocompetency during Stress and Bacterial ChallengeJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 4 2008Jesse T. Trushenski We evaluated the effects of dietary vitamin E concentration and source on production performance and immunocompetency of sunshine bass, Morone chrysops × Morone saxatilis, following stress and disease challenge. Four diets were formulated to contain requisite levels (1×) or five times (5×) the vitamin E requirement of sunshine bass as met by synthetic vitamin E (SYNE) or natural source vitamin E (NSVE). Each diet was fed to juvenile sunshine bass for 8 wk prior to experimental challenges. Replicate tanks within each dietary treatment were challenged with stressor exposure (chasing with dip net), incidental Flavobacterium columnare exposure, or both; control groups were not challenged. Pathogen and/or stressor exposure largely resulted in significant reductions in immunological performance. Although significant independent dietary effects were not observed among immunological parameters, suppression of complement and macrophage respiratory burst activities was numerically lower within the 5× NSVE treatment. Production performance was largely unaffected by dietary vitamin E source or level. Fillet ,-tocopherol concentration was significantly higher among fish fed the 5× diets (40.7/41.6 vs. 12.2/14.5 ,g/g dry tissue for 1× diets); however, the dietary concentration required to achieve these levels was lower for NSVE. Although super-requirement levels of either source of vitamin E were apparently beneficial, NSVE was effective at ,50% lower supplementation levels. [source] FACTORS AFFECTING LIPID OXIDATION IN BREAST AND THIGH MUSCLE FROM CHICKEN, TURKEY AND DUCKJOURNAL OF FOOD BIOCHEMISTRY, Issue 4 2010Y. GONG ABSTRACT Lipid oxidation occurred rapidly in turkey muscle, intermediate in duck and slowest in chicken. pH was lowest in turkey muscle. Chicken muscle had a lower content of polyunsaturated fatty acids compared with turkey and duck muscles. The aqueous fraction of duck breast inhibited hemoglobin-mediated lipid oxidation in washed muscle more effectively than aqueous fractions from turkey and chicken muscle. ,-Tocopherol content was highest in duck muscle, intermediate in chicken and lowest in turkey. Depletion of tocopherols during frozen storage was more rapid in turkey and duck compared with chicken. It was thought that the elevated tocopherol level in chicken muscle may be caused by less efficient catabolism via the omega hydroxylation pathway. However, tocopherol hydroxylase activity was similar in chicken compared with turkey liver microsomes. Heme pigment content was around sixfold higher in duck breast compared with chicken and turkey breast. Duck thigh had especially elevated pH. PRACTICAL APPLICATIONS This work describes a number of factors that explain the wide variation in oxidative stability (chicken > duck > turkey) when comparing muscle tissues from the three avian species. These factors include muscle pH, concentration of heme pigments, fatty acid unsaturation, inhibitors of lipid oxidation in the aqueous fraction of the muscle, tocopherol content in lipid phases and depletion rates of tocopherol. These factors should be considered when developing strategies to inhibit lipid oxidation in muscle foods. The relatively high content of ,-tocopherol in chicken muscle compared with turkey should be a subject of further research to better understand the mechanisms by which certain animal species preferentially deposit the molecule into muscle. [source] Seed roasting improves the oxidative stability of canola (B.,napus) and mustard (B.,juncea) seed oilsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 4 2008Chakra Wijesundera Abstract Animal fats and partially hydrogenated vegetable oils (PHVO) have preferentially been used for deep-frying of food because of their relatively high oxidative stability compared to natural vegetable oils. However, animal fats and PHVO are abundant sources of saturated fatty acids and trans fatty acids, respectively, both of which are detrimental to human health. Canola (Brassica napus) is the primary oilseed crop currently grown in Australia. Canola quality Indian mustard (Brassica juncea) is also being developed for cultivation in hot and low-rainfall areas of the country where canola does not perform well. A major impediment to using these oils for deep-frying is their relatively high susceptibility to oxidation, and so any processing interventions that would improve the oxidative stability would increase their prospects of use in commercial deep-frying. The oxidative stability of both B.,napus and B.,juncea crude oils can be improved dramatically by roasting the seeds (165,°C, 5,min) prior to oil extraction. Roasting did not alter the fatty acid composition or the tocopherol content of the oils. The enhanced oxidative stability of the oil, solvent-extracted from roasted seeds, is probably due to 2,6-dimethoxy-4-vinylphenol produced by thermal decarboxylation of the sinapic acid naturally occurring in the canola seed. [source] Determination of tocopherols and phytosterols in sunflower seeds by NIR spectrometryEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 5 2007Alicia Ayerdi Gotor Abstract The objective of this work was to develop a near-infrared reflectance spectrometry (NIRS) calibration estimating the tocopherol and phytosterol contents in sunflower seeds. Approximately 1000 samples of grinded sunflower kernels were scanned by NIRS at 2-nm intervals from 400 to 2500,nm. For each sample, standard measurements of tocopherol and phytosterol contents were performed. The total tocopherol content was obtained by high-performance liquid chromatography coupled with a fluorescence detector, while the total phytosterol content was assessed by gas chromatography. For tocopherol, the calibration data set ranged from 175 to 1005,mg/kg oil (mean value around 510,±,140,mg/kg oil), whereas for the phytosterol content, the calibration data set ranged from 180 to 470,mg/100,g oil (mean value of 320,±,50,mg/100,g oil). The NIRS calibration showed a relatively good correlation (R2,=,0.64) between predicted by NIRS and real values for the total tocopherol content but a poor correlation for the total phytosterol content (R2,=,0.27). These results indicate that NIRS could be useful to classify samples with high and low tocopherol content. In contrast, the estimation of phytosterol contents by NIRS needs further investigation. Moreover, in this study, calibration was obtained by a modified partial least-squares method; the use of other mathematical treatments can be suitable, particularly for total phytosterol content estimation. [source] Fatty acid composition, antioxidants and lipid oxidation in chicken breasts from different production regimesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2004Kishowar Jahan Summary Chicken breast from nine products and from the following production regimes: conventional (chilled and frozen), organic and free range, were analysed for fatty acid composition of total lipids, preventative and chain breaking antioxidant contents and lipid oxidation during 5 days of sub-ambient storage following purchase. Total lipids were extracted with an optimal amount of a cold chloroform methanol solvent. Lipid compositions varied, but there were differences between conventional and organic products in their contents of total polyunsaturated fatty acids and n-3 and n-6 fatty acids and n-6:n-3 ratio. Of the antioxidants, , -tocopherol content was inversely correlated with lipid oxidation. The antioxidant enzyme activities of catalase, glutathione peroxidase and glutathione reductase varied between products. Modelling with partial least squares regression showed no overall relationship between total antioxidants and lipid data, but certain individual antioxidants showed a relationship with specific lipid fractions. [source] Effect of dietary copper and vitamin E supplementation, and extensive feeding with acorn and grass on longissimus muscle composition and susceptibility to oxidation in Iberian pigsJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 9-10 2001A. I. Rey The objective of this study was to assess the effect of dietary copper and/or vitamin E supplementation on composition and oxidation of M. longissimus in Iberian pigs and to compare it with meat samples from pigs produced extensively and fed with acorn and grass. Grass had the highest ,-tocopherol content (> 150 mg/kg DM), while acorns had the highest copper concentration (78.1 mg/kg DM). Dietary treatment did not affect copper composition in muscle and no interactions were detected between copper and ,-tocopherol. The ,-tocopherol content in muscle from pigs fed diets supplemented with ,-tocopheryl acetate (100 mg/kg feed) was 1.5 times greater (p < 0.0001) than those from pigs receiving a basel diet. M. longisssimus dorsi from pigs fed extensively had a higher concentration of ,-tocopherol than those fed in confinement with the basel level of ,-tocopheryl acetate, but lower values than pigs fed supplemented levels. Total n -3 fatty acids (p < 0.02) and hematin (p < 0.0001) concentrations were significantly higher in muscle from pigs fed extensively than when fed in confinement. Muscle homogenates from Iberian pigs fed in extensive conditions showed significantly (p < 0.02) higher susceptibility to oxidation than those from pigs fed mixed diets. Dietary ,-tocopheryl acetate supplementation (100 mg/kg feed) significantly (p < 0.05) reduced lipid oxidation of muscle, while dietary copper concentration did not modify susceptibility to lipid oxidation. Das Ziel dieses Studiums war die Wirkung von Kupfer und Vitamin E Ergänzung im Futter auf die Zusammenstellung und Oxydation von M. longissimus in Iberischen Schweinen zu erforschen und es mit Fleisch-Beispielen von freilaufenden Schweinen zu vergleichen, die mit Eicheln und Gras gefüttert wurden. Gras hatte den höchsten ,-Tocopherolgehalt (> 150 mg/kg), während Eicheln die höchste Kupferkonzentration hatten (78.1 mg/kg). Diätgemäße Behandlung von Kupfer beeinflußte keine kupferne Zusammenstellung im Muskel. Es wurden auch keine Wechselwirkungen zwischen Kupfer und ,-Tocopherol entdeckt. Der ,-Tocopherolgehalt im Muskel von Schweinen, gefüttert mit ,-Tocopherolacetat-Ergänzung (100 mg/kg füttern), war bedeutend größer (p < 0.0001) als jener von Schweinen, die eine fundamentale Nahrung bekamen. Der M. longisssimus dorsi von in Freilauf ernährten Schweinen hatte eine höhere ,-Tocopherol-Konzentration, als der von Schweinen, die mit einem fundamentalen Gehalt an ,-Tocopherolacetat gefüttert wurden (p < 0.0001), aber geringer als der von mit ,-Tocopherol-Ergänzung gefütterten Schweine. Der Gehalt von n -3 Fettsäuren (p < 0.02) und Hematin (p < 0.0001) war beträchtlich höher im Muskel von im Freilauf gefütterten Schweinen, als der von mit konzentrierter Nahrung gefütterten Schweinen. Muskel-Homogenate von freilaufenden Iberischen Schweinen zeigten bedeutend (p < 0.02) höhere Anfälligkeit zu Oxydation, als jene von Schweinen, die mit gemischter Nahrungen gefüttert wurden. Diätgemäße ,-Tocopherolazetat-Ergänzung (100 mg/kg füttern) zeigte bedeutend (p < 0.05) reduzierte lipoide Oxydation des Muskels, während diätgemäße kupferne Konzentration die Anfälligkeit zu lipoider Oxydation nicht modifizierte. [source] FACTORS AFFECTING LIPID OXIDATION IN BREAST AND THIGH MUSCLE FROM CHICKEN, TURKEY AND DUCKJOURNAL OF FOOD BIOCHEMISTRY, Issue 4 2010Y. GONG ABSTRACT Lipid oxidation occurred rapidly in turkey muscle, intermediate in duck and slowest in chicken. pH was lowest in turkey muscle. Chicken muscle had a lower content of polyunsaturated fatty acids compared with turkey and duck muscles. The aqueous fraction of duck breast inhibited hemoglobin-mediated lipid oxidation in washed muscle more effectively than aqueous fractions from turkey and chicken muscle. ,-Tocopherol content was highest in duck muscle, intermediate in chicken and lowest in turkey. Depletion of tocopherols during frozen storage was more rapid in turkey and duck compared with chicken. It was thought that the elevated tocopherol level in chicken muscle may be caused by less efficient catabolism via the omega hydroxylation pathway. However, tocopherol hydroxylase activity was similar in chicken compared with turkey liver microsomes. Heme pigment content was around sixfold higher in duck breast compared with chicken and turkey breast. Duck thigh had especially elevated pH. PRACTICAL APPLICATIONS This work describes a number of factors that explain the wide variation in oxidative stability (chicken > duck > turkey) when comparing muscle tissues from the three avian species. These factors include muscle pH, concentration of heme pigments, fatty acid unsaturation, inhibitors of lipid oxidation in the aqueous fraction of the muscle, tocopherol content in lipid phases and depletion rates of tocopherol. These factors should be considered when developing strategies to inhibit lipid oxidation in muscle foods. The relatively high content of ,-tocopherol in chicken muscle compared with turkey should be a subject of further research to better understand the mechanisms by which certain animal species preferentially deposit the molecule into muscle. [source] SIMULATION OF THIN-FILM DEODORIZERS IN PALM OIL REFININGJOURNAL OF FOOD PROCESS ENGINEERING, Issue 2010ROBERTA CERIANI ABSTRACT As the need for healthier fats and oils (natural vitamin and trans fat contents) and interest in biofuels are growing, many changes in the world's vegetable oil market are driving the oil industry to developing new technologies and recycling traditional ones. Computational simulation is widely used in the chemical and petrochemical industries as a tool for optimization and design of (new) processes, but that is not the case for the edible oil industry. Thin-film deodorizers are novel equipment developed for steam deacidification of vegetable oils, and no work on the simulation of this type of equipment could be found in the open literature. This paper tries to fill this gap by presenting results from the study of the effect of processing variables, such as temperature, pressure and percentage of stripping steam, in the final quality of product (deacidified palm oil) in terms of final oil acidity, the tocopherol content and neutral oil loss. The simulation results have been evaluated by using the response surface methodology. The model generated by the statistical analysis for tocopherol retention has been validated by matching its results with industrial data published in the open literature. PRACTICAL APPLICATIONS This work is a continuation of our previous works (Ceriani and Meirelles 2004a, 2006; Ceriani et al. 2008), dealing with the simulation of continuous deodorization and/or steam deacidification for a variety of vegetable oils using stage-wised columns, and analyzing both the countercurrent and the cross-flow patterns. In this work, we have studied thin-film deodorizers, which are novel equipment developed for steam deacidification of vegetable oils. Here, we highlight issues related to final oil product quality and the corresponding process variables. [source] ,-Carotene-Loaded Nanostructured Lipid CarriersJOURNAL OF FOOD SCIENCE, Issue 2 2008A. Hentschel ABSTRACT:, Nanostructured lipid carriers (NLC) technology was used to disperse hydrophobic ,-carotene in an aqueous phase. NLC are lipid nanoparticles with a particle matrix consisting of a blend of a liquid and solid lipid. They were produced by melting the lipid blend at 80 °C and dispersing it into a hot emulsifier solution. The aim of this study was to extend the limited knowledge of melt-emulsified lipidic colloids in food systems and to evaluate the feasibility for further applications as functional ingredient in beverages. Physical stability of the NLC suspension was examined at 2 different storage temperatures by measuring the particle size with photon correlation spectroscopy (PCS) and laser diffractometry (LD). All particles containing sufficient amounts of emulsifier were smaller than 1 ,m (LD diameter 100%) at a mean particle size of around 0.3 ,m (LD) for 9 wk at 20 °C and at least 30 wk at 4 to 8 ° C. Differential scanning calorimetry (DSC) was used to study the solid state of the lipids both in the ,-carotene loaded PGMS and in the NLC particles. Propylene glycol monostearate (PGMS) when dispersed as NLC recrystallized up to 98% during storage time. Within the regarded period of 7 mo no polymorph transitions were observed. Furthermore, stability of the ,-carotene in water dependent on NLC concentration and tocopherol content was measured photospectrometrically to get an estimation of the behavior of NLC in beverages. [source] Stability of Crude Herring Oil Produced from Fresh Byproducts: Influence of Temperature during StorageJOURNAL OF FOOD SCIENCE, Issue 9 2002I. Aidos ABSTRACT: Crude herring oil, extracted from fresh byproducts, was stored at 0, 20, and 50°C in order to study the effect of temperature on lipid oxidation. The oil had an initial peroxide value (PV), anisidine value (AV), and free fatty acids of 0.7 meq peroxides/kg of lipid, 0.4, and 0.6%, respectively. During storage, the oil reached the secondary oxidation stage for all 3 temperatures. The formation of fluorescent compounds was inhibited at 0°C. Significant decrease of the ,-tocopherol content was found after storage at 0 and 20°C, but no consumption occurred at 50°C. The development of oxidation products over time exhibited a temperature-dependency with a very good correlation. [source] Stability of Tocopherols and Retinyl Palmitate in Snack ExtrudatesJOURNAL OF FOOD SCIENCE, Issue 6 2001K. Suknark ABSTRACT: Fish- and peanut-containing half-products were obtained by extruding and drying tocopherol- and retinyl palmitate-fortified mixtures of tapioca starch and minced fish or partially defatted peanut flour (PDPF 60:40, wet basis). Half-products were puffed by deep-fat frying. Vitamins were determined simultaneously at each step of snack production using a direct solvent extraction method. Extrusion significantly reduced the content of tocopherols and retinyl palmitate in both products. Reduction of retinyl palmitate in fish and peanut extrudates during snack production was 48% and 27%, respectively. Final products contained more tocopherol than intermediates because of the high tocopherol content in the frying oil and its uptake. [source] Physicochemical properties, total phenol and tocopherol of some Acacia seed oilsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2008Olumuyiwa S Falade Abstract BACKGROUND: Recently, there has been an increase in the number of investigations into the possible use of vegetable oils as a source of oleochemicals to supplement petrochemicals. We have therefore determined the physicochemical properties of Acacia oils and compared them with groundnut oil as a first step toward their possible industrial utilization. RESULTS: The chemical properties of Acacia oils compared well and surpassed those of groundnut oil in iodine value (1549.3, 1783.3 and 1093.1 g iodine kg,1 oil for A. colei, A. tumida and groundnut oils, respectively), saponification value (201.74, 202.15 and 198.01 g KOH kg,1 oil for A. colei, A. tumida and groundnut oils, respectively). Total phenol and tocopherol content of Acacia oils were also higher compared with groundnut oil. Refractive index, specific gravity and viscosity were higher in Acacia seed oils than in groundnut oil but the smoke point of Acacia oil was lower than that of groundnut oil. Acacia oils were higher in some essential elements (Mg, Ca, Fe, Zn and Cu) when compare with groundnut oil. CONCLUSION: The properties of Acacia oils revealed that they could be useful as drying oils, in soap making and as lubricants at low temperatures. They could also be dietary sources of natural antioxidants and essential elements. Copyright © 2007 Society of Chemical Industry [source] A survey of sesamin and composition of tocopherol variability from seeds of eleven diverse sesame (Sesamum indicum L.) genotypes using HPLC-PAD-ECDPHYTOCHEMICAL ANALYSIS, Issue 4 2008Kelly S. Williamson Abstract The objective of this study was to determine the composition and content of sesamin and desmethyl tocopherols such as , -tocopherol (,T), , -tocopherol (,T) and , -tocopherol (,T) in seeds of sesame (Sesamum indicum L.) for 11 genotypes conserved in the United States Department of Agriculture (USDA), Agricultural Research Service (ARS) and Plant Genetic Resources Conservation Unit (PGRCU) in Griffin, Georgia, USA. Seed accessions studied were collections from eight countries worldwide, including one landrace from Thailand and two cultivars from Texas, USA. Novel methodologies and analytical techniques described herein consisted of reverse-phase high-performance liquid chromatography (HPLC) connected in series with two detection systems specific for each analyte class. Photodiode array detection was employed for sesamin analysis and electrochemical array detection was used in the determination of tocopherols. A preliminary study was conducted to assess sesamin levels in 2003 and tocopherol levels in 2004 from sesame seed samples conserved at the USDA, ARS and PGRCU. In 2005, sesame seed samples were grown, harvested and evaluated for sesamin as well as tocopherol levels. The overall results (n = 3) showed that sesamin, ,T, ,T and ,T levels were 0.67,6.35 mg/g, 0.034,0.175 µg/g, 0.44,3.05 µg/g and 56.9,99.3 µg/g respectively, indicating that the sesame seed accessions contained higher levels of sesamin and ,T compared with ,T and ,T. Statistical analysis was conducted and significant differences were observed among the 11 different sesame genotypes. This suggests that genetic, environmental and geographical factors influence sesamin and desmethyl tocopherol content. Copyright © 2007 John Wiley & Sons, Ltd. [source] Genetic analysis of tocopherol content and composition in winter rapeseedPLANT BREEDING, Issue 2 2001F. D. Goffman Abstract The improvement of the nutritional value and the stability properties of rapeseed oil is partly hindered by the lack of information on the genetic control of tocopherols. The objectives of this investigation were to characterize the inheritance of tocopherols by using two factorial mating designs (North Carolina Design II, NCII). The first (NCII -A) was produced with two sets of nine parents each, one selected for high and the other for low total tocopherol contents. In the second (NCII -B), each set consisted of six parents, which were either high or low for the ,/,-tocopherol ratio. Parents and F1 hybrids from both experiments were tested under field conditions in 1998 and 1999 using a completely randomized design with two replications. Only small differences were detected between mean values of parents and F1 hybrids. General combining ability (GCA) variation in both experiments was highly significant (P < 0.01) for all tocopherol traits. Significant specific combining ability (SCA) effects were only detected for a-tocopherol in NCIIA and therefore for the ,-/,-tocopherol ratio. These results indicate that tocopherol contents and composition are controlled mainly by genes with additive effects. Interactions of F1 hybrids and GCA effects with the environment were significant for only tocopherol contents and not for tocopherol composition. [source] Distribution of ,-tocopherol in fillets of turbot (Scophthalmus maximus) and Atlantic halibut (Hippoglossus hippoglossus), following dietary ,-tocopheryl acetate supplementationAQUACULTURE NUTRITION, Issue 2 2004N. Ruff Abstract The present study investigated the distribution of , -tocopherol (vitamin E) in fillets of turbot (Scophthalmus maximus) and Atlantic halibut (Hippoglossus hippoglossus). Turbot and Atlantic halibut were fed commercial diets, supplemented with different levels of , -tocopheryl acetate at the dietary target levels of 100, 500 and 1000 mg , -tocopheryl acetate kg,1 diet. The actual levels were 72, 547 and 969 for turbot, while halibut received 189, 613 and 875 mg , -tocopheryl acetate kg,1 diet. Turbot were fed the diets for 24 weeks, while Atlantic halibut were fed for 20 weeks prior to slaughter. At the end of the feeding periods fish had reached a final weight of around 1 kg. Fish were slaughtered and filleted. From the four fillets obtained per fish, 22 samples were taken from designated areas and analysed for their , -tocopherol content. The average concentrations of , -tocopherol incorporated in turbot and Atlantic halibut increased with increasing levels of , -tocopheryl acetate in the diet. Atlantic halibut had significantly (P < 0.05) more , -tocopherol in positions 2/II and 1/I than in position 9/IX. Turbot had significantly (P < 0.05) more , -tocopherol in position 2/II than in positions 1/I, 4/IV and 11/XI. By mapping , -tocopherol concentrations in fish fillets, a high degree of quality prediction may be established. Moreover, this study may help scientists in their choice of sampling position, when investigating if , -tocopheryl acetate supplementation resulted in successful , -tocopherol incorporation. [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] Effects of Bleaching on the Properties of Roasted Sesame OilJOURNAL OF FOOD SCIENCE, Issue 1 2005Inhwan Kim ABSTRACT: Improvement in quality of roasted sesame oil was studied. Roasted sesame oil was bleached at 70 °C, 85 °C, or 100 °C for 20 min with acid-activated clay at 0.5%, 1.0%, or 3.0% (w/w) and then centrifuging at 12096 × g at 4 °C for 10 min. The color of the roasted sesame oil became lighter and the viscosity of oil decreased by bleaching. Bleaching caused a significant increase in the smoke point of the oil, from 170 °C to a range of 183 °C to 191 °C. Bleaching increased palmitic acid and decreased linoleic acid contents of roasted sesame oil. Bleaching decreased free fatty acid (FFA) and conjugated dienoic acid (CDA) contents and carbonyl values (CV) of roasted sesame oil. The more the acid clay was used, the lower were the FFA and CDA contents and CV of the oil. Amount of acid clay in bleaching of roasted sesame oil had higher effects on the color, viscosity, smoke point, FFA and CDA contents, and CV of roasted sesame oil than the bleaching temperature. Bleaching did not show a significant effect on tocopherol contents of the sesame oil. Bleaching tended to decrease sesamolin contents and increase sesamol contents in the roasted sesame oil. As the amount of acid clay and the bleaching temperature increased, the contents of sesamin and sesamolin in the oil decreased while sesamol contents increased. [source] Genetic analysis of tocopherol content and composition in winter rapeseedPLANT BREEDING, Issue 2 2001F. D. Goffman Abstract The improvement of the nutritional value and the stability properties of rapeseed oil is partly hindered by the lack of information on the genetic control of tocopherols. The objectives of this investigation were to characterize the inheritance of tocopherols by using two factorial mating designs (North Carolina Design II, NCII). The first (NCII -A) was produced with two sets of nine parents each, one selected for high and the other for low total tocopherol contents. In the second (NCII -B), each set consisted of six parents, which were either high or low for the ,/,-tocopherol ratio. Parents and F1 hybrids from both experiments were tested under field conditions in 1998 and 1999 using a completely randomized design with two replications. Only small differences were detected between mean values of parents and F1 hybrids. General combining ability (GCA) variation in both experiments was highly significant (P < 0.01) for all tocopherol traits. Significant specific combining ability (SCA) effects were only detected for a-tocopherol in NCIIA and therefore for the ,-/,-tocopherol ratio. These results indicate that tocopherol contents and composition are controlled mainly by genes with additive effects. Interactions of F1 hybrids and GCA effects with the environment were significant for only tocopherol contents and not for tocopherol composition. [source] | ||||||||||||||||