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21.
To check the influence of the conservation procedure in the chemical composition of chanterelle mushroom, phenolic compounds and organic acids of samples preserved under four different conditions (drying, freezing, conservation in olive oil and in vinegar) were determined. Phenolics and organic acids were analyzed by HPLC-DAD and HPLC-UV, respectively. The results showed that chanterelle is characterized by the presence of six phenolic compounds (3-, 4-, and 5-O-caffeoylquinic acid, caffeic acid, p-coumaric acid, and rutin) and five organic acids (citric, ascorbic, malic, shikimic, and fumaric acids). Samples preserved in olive oil also exhibited hydroxytyrosol, tyrosol, luteolin, and apigenin, whereas conservation in vinegar led to the detection of hydroxytyrosol, tyrosol, and tartaric acid in the analyzed samples. The conservation procedures to which chanterelle samples were subjected seem to affect the qualitative and quantitative phenolics and organic acids profiles.  相似文献   
22.
Chestnut (Castanea sativa) is an important basic food in rural diets and a major starch crop used in a similar way to potatoes. Chestnuts are a fundamental economic resource in the "chestnut regions" not only for the fruit but also for the chestnut wood. Chestnuts have become increasingly important with respect to human health, for example, as an alternative gluten-free flour source. Chestnuts are also a rich source of other beneficial compounds, but there have been few studies on the composition during processing. In this study, we analyzed the chemical composition of three Portuguese cultivars at different stages of industrial processing. The chestnut cultivars were Longal, Judia, and Martaínha. All three cultivars had high moisture contents but were low in ash, crude fat, and crude protein contents, with high starch and low fiber contents. The free amino acid contents, including various essential amino acids, varied depending on the cultivar. All three cultivars also had a significant content of polyphenolics with gallic acid; ellagic acid was predominant among hydrolyzable and condensed tannins. Many of these compounds are known to exert significant positive effects on human health. The one-way analysis of variance for fresh chestnut shows significant differences among the three cultivars for most of the studied parameters. The same statistical analysis applied to each one of the two cultivars (Judia and Longal) sampled for the four processing steps analyzed indicates a significant effect of this factor in practically all of the constituents. On the other hand, the two-way analysis of variance shows that, besides the residual, the processing step and the interaction cultivar x processing step were the factors that more contributed for the total variation observed in the constituents analyzed, while the contribution of cultivar was much less significant.  相似文献   
23.
Hydration of freeze-dried chicken breast meat was followed in the water activity range of aw=0.12-0.99 by a multianalytical approach comprising of sorption isotherm, differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR). The amount of frozen water and the shape of the T2-relaxogram were evaluated at each water content by DSC and NMR, respectively. Data revealed an agreement between sorption isotherm and DSC experiments about the onset of bulk water (aw=0.83-0.86), and NMR detected mobile water starting at aw=0.75. The origin of the short-transverse relaxation time part of the meat NMR signal was also reinvestigated through deuteration experiments and proposed to arise from protons belonging to plasticized matrix structures. It is proved both by D2O experiments and by gravimetry that the extra protons not contributing to the water content in the NMR experiments are about 6.4% of the total proton NMR CPMG signal of meat.  相似文献   
24.
‘Blanquilla’ pears processed as fresh-cut products are highly sensitive to browning and softening. Common postharvest methods, such as the use of antibrowning compounds and/or modified atmosphere packaging, fail to preserve ‘Blanquilla’ pear slices long enough to be marketable. However, treatment with 1-MCP before cutting and peeling considerably improved their textural properties (9.2 N vs. 1.1 N with and without 1-MCP treatment, respectively) and color (a* values of 1 vs. 5 after 15 d at 4 °C, for slices pear treated with 1-MCP and without treatment, respectively). These positive changes were closely related to a decrease in respiratory activity determined on whole pears after 3 months of storage in air at 0 ± 1 °C and 95% R.H. (0.40 ± 0.05 mmol CO2 kg−1 h−1 vs. 0.77 ± 0.04 mmol CO2 kg−1 h−1 with and without 1-MCP treatment, respectively) and ethylene production (1.18 ± 0.36 nmol C2H4 kg−1 h−1 vs. 5.751 ± 1.12 nmol C2H4 kg−1 h−1 for samples treated with and without 1-MCP, respectively). The use of 1-MCP allows fresh-cut ‘Blanquilla’ pears to be sold up to about 5 d after processing. Treatment with 1-MCP could be a viable alternative to common technologies for extending the shelf-life of ‘Blanquilla’ pears as a fresh-cut product.  相似文献   
25.
Qualitative and quantitative analyses of phenolic compounds were carried out on quince fruit samples from seven different geographical origins in Portugal. For each origin, both pulp and peel were analyzed by reversed-phase HPLC-DAD and HPLC-DAD/MS.The results revealed differences between the phenolic profiles of pulps and peels in all studied cases. The pulps contained mainly caffeoylquinic acids (3-, 4-, and 5-O-caffeoylquinic acids and 3,5-dicaffeoylquinic acid) and one quercetin glycoside, rutin (in low amount). The peels presented the same caffeoylquinic acids and several flavonol glycosides: quercetin 3-galactoside, kaempferol 3-glucoside, kaempferol 3-rutinoside, and several unidentified compounds (probably kaempferol glycoside and quercetin and kaempferol glycosides acylated with p-coumaric acid). The highest content of phenolics was found in peels.  相似文献   
26.
27.
The main purpose of this work was to conduct a kinetic study on cell growth and hexavalent chromium [Cr(VI)] removal by Candida sp. FGSFEP in a concentric draft-tube airlift bioreactor. The yeast was batch-cultivated in a 5.2-l airlift bioreactor containing culture medium with an initial Cr(VI) concentration of 1.5 mM. The maximum specific growth rate of Candida sp. FGSFEP in the airlift bioreactor was 0.0244 h?1, which was 71.83% higher than that obtained in flasks. The yeast strain was capable of reducing 1.5 mM Cr(VI) completely and exhibited a high volumetric rate [1.64 mg Cr(VI) l?1 h?1], specific rate [0.95 mg Cr(VI) g?1 biomass h?1] and capacity [44.38 mg Cr(VI) g?1 biomass] of Cr(VI) reduction in the airlift bioreactor, with values higher than those obtained in flasks. Therefore, culture of Candida sp. FGSFEP in a concentric draft-tube airlift bioreactor could be a promising technological alternative for the aerobic treatment of Cr(VI)-contaminated industrial effluents.  相似文献   
28.
Landscape Ecology - Several case studies investigated the role of ecosystem services in participatory planning processes. However, no systematic study exists that cuts across a large number of...  相似文献   
29.
In wheat, the increase of yield and stability associated traits can be achieved by combining parents containing the stay-green trait and favorable alleles for grain yield. The aim of this work was to analyze the genetic dissimilarity between wheat lines from stay-green and synchronized maturation groups and elite cultivars. Moreover, to propose promising combinations seeking the selection of high-grain yield and high bread-making quality genotypes containing stay-green trait. The experiment was conducted in a randomized block design with three replications in 2003, 2004, and 2005, using sister-lines with the presence and absence of stay-green trait and elite cultivars. Genetic variability exists among wheat strains from the synchronized stay-green maturation group and elite cultivars. Genotypes of maturation group stay-green obtained an average performance superior to the synchronized group. Crosses between stay-green lines and the CEP 29 and BRS 177 cultivars are promising in the selection of genotypes carrying the stay-green trait with high yield and bread-making quality.  相似文献   
30.
Water, Air, & Soil Pollution - The treatment efficiency of Chlorella sorokiniana and Scenedesmus species, immobilized in sodium alginate, was evaluated for removing nitrate from groundwater....  相似文献   
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