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921.
Jaime González‐Buesa Esther Arias María L. Salvador Rosa Oria Ana Ferrer‐Mairal 《International Journal of Food Science & Technology》2011,46(4):819-826
Clingstone non‐melting peach cultivars (Prunus persica L. Batsch) are used primarily for canning, but their processing as fresh‐cut products is also of interest. Four clingstone peach cultivars (‘Andross’, ‘Babygold 8′, ‘Calante’ and ‘Romea’) were evaluated for their suitability for minimal processing (washing, peeling and slicing) followed by storage for 9 days at 4 °C in a modified atmosphere using microperforated films. Romea cultivar, which has low polyphenol oxidase (PPO) enzymatic activity, proved to be the most suitable cultivar for minimal processing, given its lower degree of browning as well as the results from a sensory evaluation. Maturity indicators varied slightly during storage at a different degree depending on cultivars. We have found that PPO activity and browning potential are adequate indicators for surface browning in fresh‐cut non‐melting peaches. 相似文献
922.
The present study examines source memory for actions (e.g., placing items in a suitcase). For both young and older adult participants, source memory for actions performed by the self was better than memory for actions performed by either a known (close) or unknown other. In addition, neither young nor older adults were more likely to confuse self with close others than with unknown others. Results suggest an advantage in source memory for actions performed by the self compared to others, possibly associated with sensorimotor cues that are relatively preserved in aging. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
923.
Flávia Araújo da Fonseca Manoel Soares Soares Júnior Márcio Caliari Priscila Zaczuk Bassinello Eduardo da Costa Eifert Diva Mendonça Garcia 《International Journal of Food Science & Technology》2011,46(9):1912-1920
The objective of this work was to investigate the influence of temperature and soaking time on the quality of grains from two upland rice cultivars. Response surface methodology and a central compound rotational design were used. The data obtained for the cultivars BRS Primavera and BRS Sertaneja varied, respectively, between 27.7–55.0% and 26.0–51.7% for the Husk‐Splitting Index; between 0.8–5.0% and 0.0–4.0% for the incidence of ‘banana’ grains; between 0.0–2.0% and 0.0–1.2% for non‐gelatinised grains; and between 0.2–0.7% and 0.2–0.8% for soluble solids in the maceration water. Because BRS Primavera grains had a narrower shape, they absorbed the water faster and consequently presented a greater amount of physical defects, although the losses to the water were smaller than BRS Sertaneja. 相似文献
924.
The increasing installation of distributed energy resources during the last years has led to a fundamental change in the power system structure. As a consequence, utility operators are faced with new challenges in grid planning and control. The consideration of smart grids show promising results in increasing the hosting capacity for distributed and renewable resources. Standardized automation, control, and communication systems are important keys to realize such intelligent methods. This paper focuses on a deployment methodology of IEC 61850 on an experimental platform for smart grid system. We were interested in evaluating the performance of the GOOSE communication. A standard-based communication approach for distributed energy resources is introduced and implemented. It uses the IEC 61850 interoperability approach as well as the GOOSE communication for distributed automation. The implementation methodology is provided to handle the hierarchical architecture of distributed control applications. In order to show the advantages of the proposed methodology, a combined analytical and experimental approach is demonstrated for evaluation of GOOSE communication performances. 相似文献
925.
Acid tolerance of two strains of Listeria innocua as single strain culture and co-culture, were evaluated in liquid cheese whey after exposure to nisin, Microgard™ and green tea. Inorganic and organic acids were applied after natural antimicrobials treatments and microbial counts were made to analyze the bacterial response. The results have demonstrated that natural antimicrobials like nisin, Microgard™ and green tea, present in the liquid cheese whey, did not produce any cross-protection effects. On the contrary, in most of the cases, the antimicrobial treatment increased the susceptibility of L. innocua to acid stress, particularly in the treatment with nisin or green tea extract and organic acids. These results were corroborated by different techniques, including transmission electron microscopy. 相似文献
926.
Fabiana Aparecida Lobo Carina Levy de Aguirre Mariana Santos Silva Renato Grillo Nathalie Ferreira Silva de Melo Liliam Karla de Oliveira Leandro Cardoso de Morais Valquíria Campos André Henrique Rosa Leonardo Fernandes Fraceto 《Polymer Bulletin》2011,67(3):479-495
Due to their widespread use in agriculture as well as in urban areas, agricultural chemicals are globally some of the most
commonly encountered substances in waters. The objective of this study is to develop (including preparation and characterization)
a new modified release system for the herbicide atrazine, employing poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) microspheres.
The microspheres were prepared by the emulsification/solvent evaporation method, emulsifying an organic phase (atrazine and
PHBV dissolved in chloroform) into an aqueous phase containing polyvinyl alcohol (PVA) as surfactant, under stirring, and
then evaporating the solvent. A 24-1 fractional factorial design, investigating the influence of four variables at two levels, was performed to obtain formulations
with optimized association efficiencies. There was a greater dependence of association efficiency on PVA concentration (negative)
and the mass of polymer (positive) with lesser influence of both stirring speed and organic phase volume. The size of the
particles was assessed using scanning electron microscopy, which showed that the particles were rough-surfaced spheres. The
results obtained are promising, since the formulations presented encapsulation efficiency near 25% and the release kinetics
profile of atrazine was altered when it was encapsulated in the microparticles, indicating that these systems may be efficient
in reducing the environmental impact caused by the herbicide, hence making it safer to use. 相似文献
927.
Molecular structure characteristics,functional parameters and in vitro protein digestion of pressure‐cooked soya bean flours with different amounts of water
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Julián de la Rosa‐Millán Cristina Chuck‐Hernandez Sergio O. Serna‐Saldívar 《International Journal of Food Science & Technology》2015,50(11):2490-2497
When a food product is cooked at high temperature with different proportions of water, the differential degradation that occurs in the molecular structure promotes changes in their functional characteristics. In this study, water and soya bean flour (dry base) were mixed in different ratios (3:1, 2:1, 1:1, 0.25:1 and 0:1) and pressure cooked at 130 °C, 1.5 kg cm?2 for 30 min, cooled down to 40 °C and air dried for 24 h. Protein changes due to thermal process were determined with the ATR‐FTIR, as well as some functional parameters and in vitro protein digestibility. At higher water:soya bean flour ratios (3:1 and 2:1), the protein digestibility increased due to denaturation of tertiary structures, while urease activity (UA) and the functional characteristics of water absorption index (WAI) and water solubility index (WSI) decreased. Pearson's correlation analysis revealed that molecular changes on amide I, II and in α‐helix: β‐sheet ratios were directly related with the amount of added water. 相似文献
928.
929.
Alberto Cruz Antonio MuñozJuan Luis Zamora Rosa Espínola 《Electric Power Systems Research》2011,81(10):1924-1935
This paper empirically compares the predictive accuracy of a set of methods for day-ahead spot price forecasting in the Spanish electricity market. The methods come from time series analysis and artificial intelligence disciplines, and include univariate, multivariate, linear and nonlinear. Within the univariate methods, the double seasonal ARIMA and the recently proposed exponential smoothing for double seasonality are compared and used as benchmarks. They allow us to quantify the improvement on price forecasting when including explanatory variables or using more complex models. Dynamic regression models including the electricity load forecast are then considered. Their good performance in price forecasting has been pointed out by many authors. However, we find evidences of their predictive accuracy can be significantly outperformed by accounting the wind generation forecast provided by the System Operator. Moreover, these forecasts can be even more accurate if changes of price's behavior according with the day of the week are taken into account by means of periodic models. The last of the tested methods are feed-forward neural networks used as multivariate nonlinear regression methods with universal function approximation capabilities. The influence of the wind generation forecast on price prediction is also proved with this approach. Detailed out-of-sample results of the tested methods are given. 相似文献
930.