1,720,988 research outputs found
The influence of drying air temperature on the physical properties of dried and rehydrated eggplant
No full textDrying processes generally cause volume and surface change of foodstuffs. Information on the
porous structure and the mechanical properties of dried food products is needed for determining
food quality, process design and estimating properties such as density and moisture diffusivity.
In this work we investigated the structural changes induced in eggplant by convective air drying at
four different temperatures (40, 50, 60 and 70°C) and their effect on the subsequent rehydration
process. Drying and rehydration kinetic curves were also measured.
The changes in physical properties, such as porosity, pore-size distribution and bulk density were
determined by Hg porosimetry, Scanning Electron Microscopy and Optical Microscopy while their
effect on the textural characteristics by dynamometric measurements.
As expected, the increase of the drying air temperature causes shorter drying times. The drying
temperature influences strongly the microstructure of dried samples: the porosity increases with the
air temperature, but the structure is better preserved at intermediate temperature (60 °C) as
confirmed by the lower firmness values with respect to the other dehydrated samples (40, 50, 60
and 70°C). In these latter, the longer drying time and the higher temperature, respectively, causes
the development of a wrinkled structure. In particular, at 70 °C the structure of dehydrated samples
appears totally broken with a consequent faster water uptake during rehydration
Prolungamento della shelf-life di gamberi refrigerati
No full textDottorato di ricerca in biotecnologie degli alimenti. 13. ciclo. Tutore Marisa Di Matteo. Coordinatore Biagio MincioneConsiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome; Biblioteca Nazionale Centrale - Piazza Cavalleggeri, 1, Florence / CNR - Consiglio Nazionale delle RichercheSIGLEITItal
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Effect of Process Parameters on Partial Dealcoholizationof Wine by Osmotic Distillation
No full textThe effectiveness of the osmotic distillation process for partial dealcoholization of wine was investigated in this work. The dealcoholization process was performed using a hollow fibre membrane module and process parameters, such as hydrodynamic conditions, number of cycles, temperature and ethanol content of feed solution were investigated.
Then the partial dealcoholization of Aglianico red wine was carried out up to 2 %vol and the chemicophysical properties evaluated and compared with the initial wine. No significant differences (p<0.05) in total volatile acidity, colour, total polyphenols and organic acids content, between Aglianico and dealcoholized wine were found. Empirical correlations available in the literature for calculation of ethanol mass transfer coefficient seems able to describe with reasonable agreement the effect of operating conditions of the dealcoholization process
Evolution of quality parameters during red wine dealcoholization by osmotic distillation
No full textOsmotic distillation technique was used for the total dealcoholization of a red wine (Aglianico grape variety) up to 0.19 vol.%. The dealcoholization process was performed in subsequent cycles which gave rise wine samples at different alcoholic degrees. The effect of processing on the main chemical and physical properties of Aglianico wine was evaluated. Among wine samples, no significant differences (p < 0.05) of oenological parameters such as pH, total acidity were found. Similarly, the total phenolic, flavonoids and tartaric esters content and the composition of organic acids did not show significant differences (p < 0.05) during the process. On the contrary, colour intensity and tonality of wine samples changed significantly when the alcohol reduction was over the 6.5 vol.%. Finally, the total dealcoholized wine showed properties similar to Aglianico wine except for the volatile compounds, which decreased over 98%. Hence, flavour enrichment may be required to produce a pleasurable and delicious non alcoholic beverage from wine. (C) 2013 Elsevier Ltd. All rights reserved
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Mathematical modeling of eggplant drying: Shrinkage effect
No full textIn this paper two mathematical models with shrinkage effect describing eggplant drying are developed and discussed. The models are both modified diffusion equations and take differently into account changes of eggplant slice structure during drying. In the first model a diffusion coefficient variable with the water content is considered while in the second model a fictitious convective term is introduced. The two models are both suitable to describe the analyzed drying processes. Moreover, their equivalence is analytically demonstrated. Parameters values are estimated through a nonlinear regression procedure by comparison with the drying experiments carried out at different temperatures. Information about thickness evolution, derived from the models, are found to be in agreement with experimental data. (C) 2012 Elsevier Ltd. All rights reserved
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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