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81.
Daniel Aparecida do Amaral Teles Marcelo Fideles Braga Rosemar Antoniassi Nilton Tadeu Vilela Junqueira José Ricardo Peixoto Juaci Vitoria Malaquias 《Journal of the American Oil Chemists' Society》2016,93(2):193-199
The oil palm is currently a major source of oil used worldwide for biofuel production and food. In Brazil, it is grown in high rainfall and high temperature regions. The high cost of this oil crop in the Brazilian Amazonia, combined with environmental and land ownership issues and the occurrence of diseases, has aroused considerable interest in growing it in other regions of the country, including the Savanna (Cerrado) Biome. This study aimed to evaluate, for 1 year, the fruit bunch, the oil yield, and other parameters of two oil palm cultivars (BRS C1001 and BRS C2501) under the typical Savanna conditions in the Federal District, Brazil. Differences between these cultivars were observed in some parameters evaluated throughout the year (p < 0.05). The oil yield/bunch ranged from 25 to 32 and 29 to 36 % for BRS C2501 and BRS C1001 cultivars, respectively and similar to those obtained for the same cultivars in the Brazilian Amazonia and for other genotypes in Indonesia, Sumatra, and Malaysia. Both cultivars proved to be promising in terms of oil yield in a trail carried out at 1000 m of altitude under irrigation at Cerrado Biome in Brazil. 相似文献
82.
Patrícia Aparecida Pimenta Pereira Vanessa Rios de Souza Taísa Rezende Teixeira Fabiana Queiroz Soraia Vilela Borges João de Deus Souza Carneiro 《Food Hydrocolloids》2013
The addition of salts to carrageenan and locust bean gum gels functions to improve the characteristics of texture, thereby increasing gel strength. This effect is widely studied in gels of model systems but is studied to a lesser extent in complex systems, such as fruit preserves. The objective of this study was to evaluate the effect of adding salts on the rheological behavior of functional sugar-free guava preserves, as well as to correlate the rheological parameters. To this end, three types of texture properties were analyzed (texture profile, stress relaxation and uniaxial compression) in functional sugar-free guava preserves prepared with different concentrations of KCl and CaCl2 salt. The analyses were performed with a texturometer (Stable Micro Systems, Model TA - XT2i), and the parameters were analyzed using a Scott-Knott test at 5% probability, principal components analysis and Pearson correlation. CaCl2 was more effective for improving the characteristics of texture, especially gel strength (concentration near the F3: 0.33%), whereas KCl addition degraded gel strength. In the analysis of test relaxation, the Maxwell model parameters provided better discrimination between samples than the Peleg model parameters. Positive and negative correlations were observed, and the parameters of hardness, adhesiveness and elastic modulus ideal (E1) were the most correlated with other rheological parameters. 相似文献
83.
Karla Aparecida Guimarães GusmãoLeandro Vinícius Alves Gurgel Tânia Márcia Sacramento MeloLaurent Frédéric Gil 《Dyes and Pigments》2012,92(3):967-974
In a previous work, succinylated sugarcane bagasse (SCB 2) was prepared from sugarcane bagasse (B) using succinic anhydride as modifying agent. In this work the adsorption of cationic dyes onto SCB 2 from aqueous solutions was investigated. Methylene blue, MB, and gentian violet, GV, were selected as adsorbates. The capacity of SCB 2 to adsorb MB and GV from aqueous single dye solutions was evaluated at different contact times, pH, and initial adsorbent concentration. According to the obtained results, the adsorption processes could be described by the pseudo-second-order kinetic model. Adsorption isotherms were well fitted by Langmuir model. Maximum adsorption capacities for MB and GV onto SCB 2 were found to be 478.5 and 1273.2 mg/g, respectively. 相似文献
84.
Monise Helen Masuchi Kelly Moreira Gandra André Luis Marangoni Cristiane de Sá Perenha Ming Chih Chiu Renato Grimaldi Lireny Aparecida Guaraldo Gonçalves 《Journal of the American Oil Chemists' Society》2014,91(5):859-866
Chemical interesterification of different lipid materials has considerable potential for the production of a wide variety of special fats with improved functional and nutritional properties. The present study aimed to evaluate the chemical interesterification of blends of high-oleic sunflower oil (HOSO) and fully hydrogenated palm oil (FHPO) in the ratios (% w/w) of 80:20, 70:30, 60:40 and 50:50. The blends were characterized in triacylglycerol composition, melting point, solid fat content and crystallization behavior, and some applications in food products were suggested. The interesterification altered the solid fat content, melting point and crystallization isotherm of the samples, after the levels of trisaturated triacylglycerols decreased and disaturated–monounsaturated and monosaturated–diunsaturated triacylglycerol contents increased, due to the randomization of fatty acids. The modification in the triacylglycerol composition promoted greater miscibility between the HOSO and FHPO fractions, creating new application possibilities for the food industry. 相似文献
85.
Flavio Manoel Rodrigues da Silva Júnior Jocelita Aparecida Vaz Rocha Vera Maria Ferro Vargas 《The Science of the total environment》2009,407(23):6017-6023
This study aimed at investigating parameters of chemical extraction associated with the detection of mutagenicity in soil samples extracts. In order to evaluate the extraction efficiency of inorganic mutagens, besides the chemical analysis of metals, the Salmonella/microsome assay was performed in the preincubation and microsuspension procedures, using two solvents, and using two extraction methodologies. The efficiency of two organic compound extraction methods was compared by qualitative analysis using CG/MS in Scan mode. The results of the analysis of inorganic extracts correlated with the mutagenicity results. Mutagenic effects were detected only in the acidic extracts of soil that were shaken, in the microsuspension assay, both in the presence and absence of metabolic activation. The other conditions tested demonstrated higher cytotoxicity and negative mutagenic effects. As to the organic compounds, Accelerated Solvent Extraction (ASE) proved more effective than extraction using ultrasound (sonication). This study will help the implementation of extraction parameters to evaluate the presence of mutagenic substances in soil samples, both of inorganic and organic origins, suggesting the implementation of acidic extraction for the assessment of inorganic mutagenicity from soil samples and confirming the efficiency of ASE extraction for the assessment of organic compounds. 相似文献
86.
87.
Influence of processing on the antioxidant capacity and bioactive compounds in jellies from different blackberry cultivars 下载免费PDF全文
Vanessa Rios de Souza Patrícia Aparecida Pimenta Pereira Taísa Rezende Teixeira Thais Lomônaco Teodoro da Silva Rafael Pio Fabiana Queiroz 《International Journal of Food Science & Technology》2015,50(7):1658-1665
The effect of thermal processing and the berry cultivar has been the subject of several studies, to serve as a basis for the least possible loss of bioactive compounds and antioxidant capacity. In Brazil, there are numerous blackberry cultivars under cultivation, and in this context, the aim of this work was to study how the bioactive compound contents and antioxidant capacity of blackberry jelly were influenced by the cultivars (Guarani, Brazos, Comanche, Tupy, Cherokee, Caingangue and Choctaw). Analysis was made of 7 fresh blackberry cultivars and 7 blackberry jelly formulations. Analysis of antioxidant activity, total phenolics, total anthocyanins and ascorbic acid was performed. It was verified that the contribution of the heat sensitive antioxidants compounds is considerable in all blackberry cultivars, and the degradation of these compounds was significantly different between the different blackberry cultivars. The Brazos and Caingangue cultivars stand out as undergoing the lowest losses in processing, resulting in jellies richer in bioactive compounds and higher antioxidant capacity. 相似文献
88.
Christian Rodriguez Coronado Aparecida de Castro Villela José Luz Silveira 《Applied Thermal Engineering》2010,30(5):458-463
This paper evaluates and quantifies the environmental impact resulting from the combination of biodiesel fuel (pure or blended with diesel), and diesel combustion in thermoelectric power plants that utilize combined cycle technology (CC). In regions without natural gas, the option was to utilize diesel fuel; the consequence would be a greater emission of pollutants. Biodiesel is a renewable fuel which has been considerably interesting in Brazil power matrix in recent years. The concept of ecological efficiency, largely evaluates the environmental impact caused by CO2, SO2, NOx and particle matter (PM) emissions. The pollution resulting from biodiesel and diesel combustion is analyzed, separately considering CO2, SO2, NOx and particulate matter gas emissions, and comparing them international standards currently used regarding air quality. It can be concluded that it is possible to calculate the qualitative environmental factor, and the ecological effect, from a thermoelectric power plant utilizing central heat power (CHP) of combined cycle. The ecological efficiency for pure biodiesel fuel (B100) is 98.16%; for biodiesel blended with conventional diesel fuel, B20 (20% biodiesel and 80% diesel) is 93.19%. Finally, ecological efficiency for conventional diesel is 92.18%, as long as a thermal efficiency of 55% for thermoelectric power plants occurs. 相似文献
89.
Helena Rudge de Moraes Barros Tânia Aparecida Pinto de Castro Ferreira Maria Inés Genovese 《Food chemistry》2012
Four Citrus species (C. sinensis, cvs. Pera and Lima; C. latifolia Tanaka cv. Tahiti; C. limettioides Tanaka cv. Sweet lime and C. reticulate, cv. Ponkan) grown in Brazil were characterised in relation to contents of minerals, ascorbic acid, total polyphenols and antioxidant capacity of pulps and peels. In general, the peels demonstrated significantly higher contents of all compounds than the pulps (p < 0.05), with the exception of the Pera orange pulp that presented the highest acid ascorbic content (68 mg/100 ml), while the Tahiti lime peel presented the lowest (8 mg/100 g). Citrus showed high levels of potassium, calcium and magnesium, and the peels were considered sources of these minerals. The Ponkan mandarin peel presented the highest antioxidant capacity. The antioxidant capacity of citrus was correlated both to vitamin C and phenolics. Aside from citrus pulps, the peels are also good sources of bioactive compounds and minerals, and can be explored for their health promoting values in food products. 相似文献
90.
Elaine Aparecida Regiani de Campos Regina Negri Pagani Luis Mauricio Resende Joseane Pontes 《Scientometrics》2018,116(2):815-842
Methodi Ordinatio is a methodology used to accomplish systematic literature reviews, to build bibliographical portfolios, and to map the state of the art of a research theme. It is composed of nine phases. The 7th phase, named InOrdinatio, applies an equation that orders the papers according to its scientific relevance. The equation applies the alpha (α) element, which can vary from 0 to 10 depending on the research need of currentness and according to the researcher’s perception for its variation. Therefore, the aim of this paper is to test and analyse the variations of the alpha (α) values in the equation InOrdinatio and its influence in the qualification of the items that composes a portfolio. In order to reach this purpose, a practical application was performed and a bibliographic portfolio on the theme Horizontal Business Networks and Trust was built. Using the data from the bibliographic portfolio, the alpha values from 0 to 10 were applied and their influence on the final qualification of the articles was analysed. As a complementary objective, the areas where the methodology was successfully applied until now are also identified. The results show that the methodology is coherent, reproducible and useful to sort the most relevant articles in accordance with what is internationally recognized as valid scientific criteria: the impact factor, year of publication, and number of citations. 相似文献