1,720,964 research outputs found

    The effect of salts on acrylamide and 5-hydroxymethylfurfural formation in glucose-asparagine model solutions and biscuits

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    Increasing amounts of CH3COOK, CaCl2, MgCl2 or of a combination of CaCl2 and MgCl2 were added to a glucoseasparagine model solution or to a biscuit formulation, and their effects on acrylamide and 5-hydroxymethylfurfural (HMF) formation were studied. The results showed that in both considered systems, CH3COOK was responsible for a great increase in acrylamide (116% in the biscuits), while it inhibited HMF formation in both. On the contrary, CaCl2 and MgCl2 were effective in reducing acrylamide formation in the model solutions and, only if used in combination, they caused a 60% acrylamide reduction in the biscuits. However, these salts resulted in favouring the development of high levels of HMF. It was concluded that although the addition of some salts to foods has been suggested as a tool for reducing acrylamide formation, alternative interventions should be considered

    Applicability of monoglyceride-oil-water gel to produce low-saturated fat products

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    This study provides useful information in the task of application of monoglyceride gels in food formulation. In particular, results highlighted that the use of monoglycerides-oil-water gel as solid fat provides a valid alternative to the saturated fat matrix normally used in the production of lipid-containing foods. However, the specific interaction among ingredients should be carefully taken into account during the development of new formulations containing monoglyceride-oil-water gels

    Inactivation of pectic lyases by light exposure in model systems and fresh-cut apple

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    UV-C light exposure caused the inactivation of pectin lyases from Aspergillus japonicus and pectate lyase from apple under non-thermal conditions. Samples exposed to 20 W m(-2) UV-C light showed D(L) values, defined as the time needed for 90% enzyme activity reduction, around 20 min. However, an initial activation phase was observed for fungin pectin lyase, while UV-C light resistant forms of pectate lyase were identified in apple. Lyase inactivation occurred as a consequence of enzyme cleavage into fragments without catalytic activity having MW around 5 kDa. Fresh-cut apple slices exposed for a few minutes to UV-C light resulted significantly firmer than the untreated ones during 4 days of refrigerated storage, reasonably due to the decrease in activity of both endogenous and microbial lyases on the surface of the wound apple tissue. Industrial relevance: UV-C light blanching allows to non-thermally increase the enzymatic stability of the surface of fresh-cut fruit and vegetables

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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 low-temperature long-time pre-treatment of wheat on acrylamide concentration in short dough biscuits

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    In April 2002, unexpected high levels of the neurotoxic and suspected carcinogen acrylamide (AA) were found in many heated foods, mainly represented by cereal and potato derivatives. Since then, due to the great consumption of dietary sources of AA among people of different ages and in different countries, worldwide efforts have been carried out to reduce the formation of the toxic molecule in foods. In this paper, the effect of a low-temperature long-time pretreatment of wheat grains on AA formation in biscuits was investigated. Wheat grains were subjected to heating at 1001C for 8 h and subsequently milled. The obtained flour was used to prepare biscuits that were compared for AA content, texture and color with control samples obtained by using flour from unheated wheat. The low-temperature long-time pre-treatment was responsible for a great decrease (up to 42%) in AA levels in the biscuits, without causing significant changes in the color and texture parameters. As the pre-treatment did not cause any change in sugar and asparagine concentrations, such a reduction in AA concentration can be attributed to a difference in the thermal effect generated in the biscuits obtained by using the unheated and pre-heated flours. In fact, as the heating pre-treatment caused a 2% moisture decrease in the flour, less time at the same temperature was required to obtain biscuits with comparable moisture contents

    Variations on the Author

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    “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

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    We 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

    Dispelling the Myths Behind First-author Citation Counts

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    We 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

    Author Index

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