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71.
Maria Esperanza Torija León Villanúa Maria Aurora Zapata 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,195(5):434-436
Summary In the present work, the composition of commercial samples of Spanish red vermouths was analysed. Physicochemical parameters such as alcoholic concentration, pH, total sugars, dry extract and ashes were determined following Spanish Official Methods. Most of the samples comply with Spanish legislation for fortified wines. The major volatile components were evaluated by direct gas chromatography using 4-methyl-2-pentanol (Merck) as internal standard. It has been estimated that the concentration of higher alcohols in red vermouth is about twice the concentration in white wines.
Charakterisierung der spanischen roten Wermut-Weine
Zusammenfassung In dieser Arbeit wurde die Zusammensetzung von Handelsproben spanischer, roter Wermut-Weine analysiert. Die chemisch-physikalischen Parameter wie Alkoholkonzentration, pH, wie Zucker-, Extrakt- und Asche-Gehalt wurden durch amtliche, spanische Methoden bestimmt. Die meisten Wermutproben kommen den spanischen Gesetzen für aromatische Weine nach. Die mengenmäßig-dominierenden flüchtigen Komponenten wurden durch Direkt-Gaschromatographie mit 4-methyl-2-penthanol (interner Standard) geschätzt. Danach enthalten die roten Wermutweine ungefähr die doppelte Konzentration an höheren Alkoholen wie die weißen Weine.相似文献
72.
Amparo Alegria Reyes Barbera R. Boluda Francisca Errecalde Rosaura Farr Maria Jesús Lagarda 《Molecular nutrition & food research》1992,36(5):451-460
The relationship between cobalt, copper and zinc content of soils and the vegetables grown in them is discussed. Samples of soil and edible vegetables were taken from 15 different sites, corresponding to four agricultural areas exposed to different degrees of environmental pollution: high industrial and traffic, high industrial and urban, and low industrial and urban pollution. Elements were determined by atomic absorption spectroscopy. Variance analysis (ANOVA) was applied to cobalt, copper and zinc content of vegetables and soils in order to detect significant differences among soils of different areas and the vegetables grown there. The possible relationship between the heavy metal content of soils (total and extractable) and of the vegetables grown in them was estimated by the correlation coefficient value. Statistically significant correlations were observed between the total and extractable cobalt content of soils and of roots and bulbs (p < 0.1) and between the total copper content of soils and of inflorescences (p < 0.05). In the case of zinc no correlation was found. 相似文献
73.
Kátia Gianni de Carvalho Lima Monika Francisca Kruger Jorge Behrens Maria Teresa Destro Mariza Landgraf Bernadette Dora Gombossy de Melo Franco 《LWT》2009,42(2):491-193
The study compared the growth capability of probiotic (Lactobacillus acidophilus La05, Lactobacillus casei Lc01 and Bifidobacterium animalis Bb12) and non-probiotic (Lactobacillus delbrueckii subsp bulgaricus and Streptococcus thermophilus) cultures on twenty-one culture media grouped according to selectivity: non-selective agars, selective agars without antibiotics and MRS agars containing different combinations of lithium chloride, cystein, bile salts and antibiotics. Four of these media were selected for quantitative enumeration of L. acidophilus La05, L. casei Lc01, and B. animalis Bb12. The best culture media and incubation conditions for enumeration of the probiotic cultures were: B. animalis: MRS agar with dicloxacillin, 37 °C or 42 °C, anaerobiosis; L. acidophilus: MRS agar with bile salts, 37 °C or 42 °C, aerobiosis; L. casei: MRS agar with lithium chloride and sodium propionate, 37 °C or 42 °C, aerobiosis or anaerobiosis. Plating on MRS with glucose replaced by maltose, 37 °C or 42 °C, anaerobiosis, will distinguish probiotic from non-probiotic cultures. For enumeration of each probiotic in a mixed culture, the following media and incubation conditions were recommended: B. animalis: 4ABC-MRS, 42 °C, anaerobiosis, L. acidophilus: LC medium, 42 °C, aerobiosis or anaerobiosis and L. casei: LP-MRS, 42 °C, aerobiosis or anaerobiosis. In all experiments, differences in counts using pour plating or surface plating were not significant (P ≤ 0.05). 相似文献
74.
Seasonal variations in total fatty acid compositions of tucunaré, Cichla sp. in the Janauacá Lake of the Amazon basin were determined by GC. Saturated fatty acids (SFAs) were found to be at higher concentrations than monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) in two seasonal periods. Major fatty acids were palmitic (16:0, 48.5–51.6% of total SFA), oleic (18:1ω9, 43.9–50.2% of total MUFA), docosahexaenoic (DHA, 22:6ω3, 13.5–27.9% of total PUFA) and arachidonic acid (AA, 20:4ω6, 16.0–19.6% of total PUFA). Polyunsaturated fatty acids were the most abundant in muscle during the flood period, and more especially fatty acids 22:6ω3 (10%) and 20:4ω6 (7%). There were no significant variations amongst total lipid SFA, MUFA, and PUFA from eye sockets. The ω6 fatty acid percentages were always higher than the ω3 fatty acid percentages in tucunaré, with ω6/ω3 ratios varying between 1.02 and 1.6 in the flood and drought periods. 相似文献
75.
Andréia Assunção Soares Cristina Giatti Marques de Souza Francielle Marina Daniel Gisele Pezente Ferrari Sandra Maria Gomes da Costa Rosane Marina Peralta 《Food chemistry》2009
The antioxidant capability and total phenolic contents of methanolic extracts of Agaricusbrasiliensis in two stages of maturity, young (YB) and mature (MB), were evaluated in this work. Four complementary assays, reducing power, radical scavenging capacity, inhibition of lipid peroxidation and chelating ability for ferrous ions were used to screen the antioxidant properties of extracts. Minor differences in the composition of phenolic compounds were detected, but the extracts showed similar antioxidant activities, except for the chelating ability for ferrous ions, higher in MB than in YB. Our results support the use of both young and mature fruiting bodies of Agaricus blazei as sources of antioxidant compounds. 相似文献
76.
Vito Verardo Federico Ferioli Ylenia Riciputi Giovanna Iafelice Emanuele Marconi Maria Fiorenza Caboni 《Food chemistry》2009
This study investigated lipid oxidation in spaghetti enriched in long chain n−3 polyunsaturated fatty acids (LC n−3 PUFA) by the addition to semolina of an integrator containing eicosapentaenoic acid and docosahexaenoic acid. Two oxidative parameters were evaluated: peroxide value (PV), to assess primary oxidation and oxidised fatty acids to quantify secondary oxidation products. Functional spaghetti had a shelf life comparable to control pasta. LC n−3 PUFA were not significantly implicated in the onset of oxidation in spaghetti stored under daylight and accelerated oxidation in a laboratory heater. Storage decidedly affected shelf life: PV in functional spaghetti increased from 7.1 to 43.4 meq O2/kg of fat under light exposure over 12 months, and from 7.1 to 16.2 meq O2/kg under accelerated ageing at 55 °C for 27 days, reproducing about 18 months at room temperature. Oxidised fatty acids increased in fortified spaghetti from 4.8 to 13.8 g/100 g of fat under light exposure over 12 months and from 4.8 to 7.8 g/100 g of fat at 55 °C in 27 days. The high sensitivity of spectrophotometric and chromatographic analytical methods permitted the evaluation of primary and secondary oxidative derivatives in small amounts of fat. 相似文献
77.
Márcia G. Ventura Vekoslava Stibilj Maria do Carmo Freitas Adriano M.G. Pacheco 《Food chemistry》2009
The selenium content in fruit and vegetable samples from two regions in Portugal were analysed using hydride generation atomic fluorescence spectrometry (HG-AFS) and radiochemical nuclear activation analysis (RNAA) – two analytical methods with very low limits of detection. The lower detection limits of HG-AFS, 3 μg kg−1 and 8 μg kg−1 (according to conditions used for digestion), and for RNAA, 10 μg kg−1, meant that it was possible to determine selenium in samples previously analysed using the replicate sample instrumental nuclear activation analysis (RSINAA) with a higher detection limit associated. 相似文献
78.
In the present paper, three different approaches are proposed to model the convective drying of food. The performance of thin-layer, pure neural network and hybrid neural model is compared in a wide range of operating conditions, with two different vegetables, available either as cylinders or as slabs with different characteristic dimensions. It was found that the thin-layer model was adequate to describe food drying behavior, but it could be applied only as a fitting procedure. Pure neural models gave accurate predictions in some situations, but exhibited poor performance when tested outside the range of operating conditions exploited during their development. Finally, it was shown that hybrid neural models, formulated as a combination of both theoretical and neural network models, are capable of offering the most accurate predictions of system behavior with average relative errors never exceeding 10%, even in operating conditions unexploited during the definition of the neural part of the model. The results obtained proved that the hybrid neural paradigm is a novel and efficient modeling technique that could be used successfully in food processing, thus allowing drying process optimization to be achieved, and efficient and fast on-line controllers to be implemented. 相似文献
79.
Maria C. Thiry 《纺织导报》2012,(9):86-88
目前,纺织行业对可持续发展的关注度日益提高,在这种背景下,越来越多的纺织企业开始寻求一些工具来评估自身的可持续性程度。据Hohenstein(海因斯坦)研究院美国分公司总经理Sam Moore介绍,纺 相似文献
80.
The aim of this study was to evaluate the performance of four different extraction methods commonly used to quantify the intramuscular lipid content in meat: the Association of Analytical Chemists (AOAC) method (reference method) and methods based on the use of a solvent mixture with different polarities, such as chloroform–methanol described by Folch et al. (J Biol Chem 226:497, 1957) and Christie (1989) or hexane–isopropanol described by Hara and Radin (Anal Biochem 90:420, 1978). The following parameters were taken into account: lipid content; relative proportions of neutral and polar lipids; fatty acid composition of total, neutral, and polar lipid fractions; and phospholipid composition. The use of a combination of solvents with different polarities (Hara–Radin, Folch, and modified Folch methods) was more effective in extracting intramuscular lipids than the use of a single solvent (AOAC, reference method). The Hara–Radin method provided a cleaner lipid extract with a significantly higher content of total fatty acids than that obtained with the Folch and modified Folch methods. The lower polarity of the hexane–isopropanol mixture allowed us to obtain an extract richer in neutral lipids (triglycerides and diglycerides) and thus in saturated and monounsaturated fatty acids. The percentage distribution of individual fatty acids in the neutral lipid fraction was generally not affected by the extraction method adopted, while lipid obtained with both the Hara–Radin and Folch methods had a polar fraction with a higher percentage of polyunsaturated fatty acids. The use of the Hara–Radin method provided a polar fraction with less nonlipid material and lower phospholipid degradation. 相似文献