980 resultados para Soil physicochemical characteristics
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A biofuel was prepared from acid aqueous fraction (pH = 2) of bio-oil produced by fast pyrolysis (Bioware Technology) of lignocellulosic biomass (sugar cane residue) and tested in blends (2, 5, 10 e 20% v/v) with gasoline type C (common) marketed in Brazil. The specification tests made in the Refinery President Getúlio Vargas (PETROBRAS) showed increasing in the octane number (MON) and antiknock index (AKI) with reduction in the residue generation during the combustion. The physicochemical characteristics of the biofuel were similar that combustible alcohol allowing its use as gasoline additive.
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The ability of bacteria to attach to surface and develop into a biofilm has been of considerable interest to food industry. Electrostatic, Lifhistz-van der Waals and Lewis acid-base forces are usually considered responsible for the interactions at the interface of the bacterial adhesion. The study of microbial adhesion thermodynamic is important because it represents the reflection of microbial surface and food processing surface physicochemical characteristics. This review examines the most important aspects involved in bacterial attachment to a surface with emphases in thermodynamics of adhesion process.
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This study aimed to verify the influence of partial dehydration of "Niagara Rosada" grape clusters in physicochemical quality of the pre- fermentation must. In Brazil, during the winemaking process it is common to need to adjust the grape must when the physicochemical characteristics of the raw material are insufficient to produce wines in accordance with the Brazilian legislation for classification of beverages, which establishes the minimum alcohol content of 8.6 % for the beverage to be considered wine. Therefore, given that the reduction in the water content of grape berries allows the concentration of chemical compounds present in its composition, especially the concentration of total soluble solids, we proceeded with the treatments that were formed by the combination of two temperatures (T1-37.1ºC and T2-22.9 ºC) two air speeds (S1: 1.79 m s-1 and S2: 3.21 m s-1) and a control (T0) that has not gone through the dehydration treatment. Analysis of pH, Total Titratable Acidity (TTA) were performed in mEq L-1, Total Soluble Solids (TSS) in ºBrix, water content on a dry basis and Concentration of Phenolic Compounds (CPC) in mg of gallic acid per 100g of must. The average comparison test identified statistically significant modifications for the adaptation of must for winemaking purposes, having the treatment with 22.9 ºC and air speed of 1.79 m s-1 shown the largest increase in the concentration of total soluble solids, followed by the second best result for concentration of phenolic compounds.
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The aim of the present study was to evaluate the acidification of the endosome-lysosome system of renal epithelial cells after endocytosis of two human immunoglobulin lambda light chains (Bence-Jones proteins, BJP) obtained from patients with multiple myeloma. Renal epithelial cell handling of two BJP (neutral and acidic BJP) was evaluated by rhodamine fluorescence. Renal cells (MDCK) were maintained in culture and, when confluent, were incubated with rhodamine-labeled BJP for different periods of time. Photos were obtained with a fluorescence microscope (Axiolab-Zeiss). Labeling density was determined on slides with a densitometer (Shimadzu Dual-Wavelength Flying-Spot Scanner CS9000). Endocytosis of neutral and acidic BJP was correlated with acidic intracellular compartment distribution using acridine orange labeling. We compared the pattern of distribution after incubation of native neutral and acidic BJP and after complete deglycosylation of BJP by periodate oxidation. The subsequent alteration of pI converted neutral BJP to acidic BJP. There was a significant accumulation of neutral BJP in endocytic structures, reduced lysosomal acidification, and a diffuse pattern of acidification. This pattern was reversed after total deglycosylation and subsequent alteration of the pI to an acidic BJP. We conclude that the physicochemical characteristics of BJP interfere with intracellular acidification, possibly explaining the strong nephrotoxicity of neutral BJP. Lysosomal acidification is fundamental for adequate protein processing and catabolism.
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The physical and physicochemical characteristics of blueberry (Vaccinium myrtillus) fruits produced in Brazil were analyzed. Rheological properties were measured at 5, 25, 45 and 65 °C, on a stress controlled rheometer equipped with grooved a stainless-steel parallel-plate in a shear rate range of 0-300 s-1, with the objective of determining the influence of temperature on the rheological properties. The pseudoplastic behavior with yield stress was well described by the Ostwald-de-Waele (Power Law), Herschel-Bulkley (HB) and Mizhari Berk models. The yield stress and behavior index decreased with the increase in the temperatures for 5, 25, and 45 °C whereas for the temperature of 65 °C the effects were the opposite exhibiting elevated values. The viscosity decreased with an increase in temperature, and the Arrhenius equation described adequately the effect of temperature on the apparent viscosity of the puree, in which the activation energy (Ea) determined at a shear rate of 100 s-1 was 9.36 kJ.mol-1.
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Sixteen common bean cultivars were compared concerning the physicochemical characteristics of their raw seeds in the course of two consecutive harvests, as well as the effect of storage conditions on starch and dietary fiber content of cooked beans. Using cluster analysis it was possible to identify groups of cultivars with different nutritional features. Bean cultivars were categorized into four different groups according either to their macronutrient content (crude protein-PROT, total dietary fiber-TDF, insoluble dietary fiber-IDF, soluble dietary fiber-SDF, digestible starch-DS, and resistant starch-RS) or to their micronutrient levels (Fe, Zn, Mn, Cu, Ca, Mg, and P). Guateian 6662 and Rio Tibagi appeared to be the most suitable cultivars to prevent nutritional deficiencies, because they had high PROT, DS, Fe, and Zn content. The high total dietary fiber and RS content of Iraí, Minuano, and TPS Bonito cultivars, and specially the high soluble fiber content of Guateian 6662 and Rio Tibagi cultivars suggests that they could have a beneficial role in controlling blood lipid and glucose levels. Cooked beans had a decrease in DS and an increase in RS content after storage (4 °C or -20 °C), but these changes were more prominent in beans that had low RS content before cooking than in those of high RS content. TDF, IDF, and SDF did not change after storage.
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Cassava starch is a valued raw material for producing many kinds of modified starches for food applications. Its physicochemical properties, as well as its availability, have made it an interesting and challenging ingredient for the food industry. In the present work, food grade modified cassava starches were purchased from producers and analyzed for selected physicochemical characteristics. Samples of sour cassava starch were included, as well as one sample of native cassava starch. Results showed that almost all modified starches were resistant to syneresis, produced pastes more stable to stirred cooking, and some of them were difficult to cook. The sour cassava starches presented high acidity and resulted in clear and unstable pastes during stirred cooking, susceptible to syneresis.
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The physicochemical characteristics, fatty acid, tocopherol, and carotenoid composition of a crude oil extracted from papaya (Carica papaya L.) seeds, formosa variety, were investigated. The oil yield from the seeds was 29.16%. The data obtained for the analytical indexes were in agreement with those of other edible oils. The oil obtained had high oxidation resistance (77.97 hours). The major fatty acids in total lipid were oleic (71.30%), palmitic (16.16%), linoleic (6.06%), and stearic (4.73%) acid. The α and δ-tocopherol were the predominant tocopherols with 51.85 and 18.89 mg.kg-1, respectivelly. The β-cryptoxanthin (4.29 mg.kg-1) and β-carotene (2.76 mg.kg-1) were the carotenoids quantified, and the content of total phenolic compounds was 957.60 mg.kg-1. Therefore, the potential utilization of the papaya seeds for oil production seems favorable. However, toxicological studies need to be carried out before the oil is appropriate for food applications.
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This study investigated the degradation kinetics of the sensory attributes of commercial whole mango (cv. Ubá) juice and evaluated its sensory acceptability during storage. Samples of the product were stored in a BOD incubator at 25, 35, and 45 ºC under 24 hours light (650 lux) for 120 days. Sensory analyses (Quantitative Descriptive Analysis - QDA) were conducted with trained panel and consumers. The correlations between sensory and physicochemical characteristics (instrumental color and vitamin C content) were also assessed. Flavor, aroma, and color vary with temperature and time of storage. Aroma and flavor were most affected by temperature with values of Q10 and Ea equal to 4.16 and 25.31 kcal.mol-1; and 3.61 and 22.80 kcal.mol-1, respectively. The sensory changes observed by the trained panel are related to the degradation of vitamin C and changes in the color coordinates (L* and ΔE*) of mango juice. However, consumers were unable to detect changes in the overall quality of the juices. It was observed that the QDA can be a useful tool to assess shelf-life.
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Sweeteners based on stevia extract contain a series of diterpene glycosides derivatives from steviol, standing out the rebaudioside-A. There is no tabletop sweeteners in the market formulated purely with rebaudioside-A yet, so its use in foods depends on the development of new products followed by physicochemical and sensory evaluations. This work presents the formulation of a diet strawberry jam dyed with cranberry juice and sweetened with rebaudioside-A purified from stevia plants of the lineage UEM-320 developed in the Centro de Estudos de Produtos Naturais da Universidade Estadual de Maringá. Evaluations of physicochemical properties, microbiological and sensory characteristics were carried out for the product in comparison with a control sweetened with equal amount of sucralose. The results showed that the physicochemical characteristics of the sample and the control are not significantly different and the supplementation with cranberry juice increased both color and total phenolic content in both samples. The sensory acceptability indicated a significant preference for the formulation sweetened with 100% of rebaudioside-A, only in the items flavor and purchase intent. We concluded that rebaudioside-A has a better sensory performance than sucralose, even this last one being 1.33 fold sweeter than rebaudioside-A.
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The aim of this study was to evaluate of Pleurotus sajor-caju production in peach palm leaves and the addition of different fractions of mushroom powder to wheat flour to increase its nutritional value without changing its characteristics. The best yield (48.4%), biologic efficiency (4.5%), and Pr (0.36 g/day) values were obtained using 20% inoculum fraction and 10% rice bran fraction. The Pleurotus sajor-caju fruiting body cultivated under these conditions had the following composition in 100 g: 29.91 g (carbohydrates), 42.92 g (proteins), 1.24 g (lipids), 15.93 g (fibers), 7.42 g (ashes), 1.6 g (phosphorus), 2.7 g (potassium), 8.73 mg (iron), 23.75 mg (sodium), 0.34 mg (thiamine), and 0.57 mg (riboflavin). The wheat flour with mushroom powder had reduced sugar content, but it did not have increased fat content. The fiber, protein, phosphorus, potassium, iron, and riboflavin contents were increased mainly when 10% mushroom powder was added to the wheat flour. Furthermore, this flour does not undergo drastic alterations in its physicochemical characteristics such as in moisture, wet gluten, color, and falling number.
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The tiniest Union territory of India, Lakshadweep, is an archipelago, with an area of 32 Sq. km. consisting of 12 atolls, three reefs and five submerged banks, lies between 8° and 12°30'N latitudes and 71° and 74" E longitudes. It is one of the most important and critical territories of India from economic and defence point of view. Specialised environment having typical geological set up, Lakshadweep is ecologically sensitive to even slight climatic or anthropogenic interference. Pollution of coastal seas, over exploitation and contamination of the fresh water sources are thus become great concerns to the existence of the island. Typical geological set up and interference cause threat to the ecology of the fragile environment and resources of the island as well as its resources. Marine pollution and ground water contamination are concerns in this regard. Even though attentions were made to assess the physico—chemical and bacteriological status of the marine and groundwater systems separately, an integrated approach has not been evolved. The present study with its broad objectives is attempted for an integrated assessment of microbiological, physicochemical and biological characteristics of the surrounding seawater and microbiological and physico—chemical characteristics of the ground water in Kavaratti island. The entire study has been organised in 4 chapters
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The present study was undertaken to evaluate the effectiveness of a few physico-chemical and biological methods for the treatment of effluents from natural rubber processing units. The overall objective of this study is to evaluate the effectiveness of certain physico-chemical and biological methods for the treatment of effluents from natural rubber processing units. survey of the chemical characteristics of the effluents discharged from rubber processing units showed that the effluents from latex concentration units were the most polluting
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Rennet-induced curd was made from both natural buffalo and cows’ milk, and ultrafiltered cows’ milk (cows’ milk was concentrated such that it had a chemical composition approximately equivalent to that of the buffalo milk). These milk samples were compared on the basis of their rheology, physicochemical characteristics and curd microstructure. The ionic and soluble calcium contents were found to be similar in all milk samples studied. The total and casein bound calcium were higher in concentrated cows’ milk than in standard cows’ milk. Both cows’ milk types were found to have lower total and casein bound calcium than the buffalo milk. This is probably due to concentration of the colloidal part of milk (casein), during the ultrafiltration (UF) process. The rennet coagulation time was similar in UF cows’ and buffalo milk while both were shorter when compared with that of the cows’ milk. The dynamic moduli (G′, G″) values were higher in both the buffalo and UF cows’ milk than in the cows’ milk after 90 min coagulation. The loss tangent, however, was found to be similar in both the UF cows’ and buffalo milk curds and was lower than that observed for the cows’ milk (0.42, 0.42 and 0.48, respectively). The frequency profile of each type of curd was recorded 90 min after the enzyme addition (0.1–10 Hz); all samples were found to be “weak” viscoelastic, frequency dependent gels. The yield stress was also measured 95 min after the enzyme addition, and a higher value was observed in buffalo milk curd when compared with other curd samples made from both the natural cows’ milk and the UF cows’ milk. The cryo-scanning electron and confocal laser scanning micrographs showed that curd structure appeared to be more “dense” and less porous in buffalo milk than cows’ milk even after concentration to equivalent levels of protein/total solids to those found in the buffalo milk.
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This paper introduces and evaluates DryMOD, a dynamic water balance model of the key hydrological process in drylands that is based on free, public-domain datasets. The rainfall model of DryMOD makes optimal use of spatially disaggregated Tropical Rainfall Measuring Mission (TRMM) datasets to simulate hourly rainfall intensities at a spatial resolution of 1-km. Regional-scale applications of the model in seasonal catchments in Tunisia and Senegal characterize runoff and soil moisture distribution and dynamics in response to varying rainfall data inputs and soil properties. The results highlight the need for hourly-based rainfall simulation and for correcting TRMM 3B42 rainfall intensities for the fractional cover of rainfall (FCR). Without FCR correction and disaggregation to 1 km, TRMM 3B42 based rainfall intensities are too low to generate surface runoff and to induce substantial changes to soil moisture storage. The outcomes from the sensitivity analysis show that topsoil porosity is the most important soil property for simulation of runoff and soil moisture. Thus, we demonstrate the benefit of hydrological investigations at a scale, for which reliable information on soil profile characteristics exists and which is sufficiently fine to account for the heterogeneities of these. Where such information is available, application of DryMOD can assist in the spatial and temporal planning of water harvesting according to runoff-generating areas and the runoff ratio, as well as in the optimization of agricultural activities based on realistic representation of soil moisture conditions.