Influence of amyloglucosidase in bread crust properties

Enzymes are used in baking as a useful tool for improving the processing behavior or properties of baked products. A number of enzymes have been proposed for improving specific volume, imparting softness, or extend the shelf life of breads, but scarce studies have been focused on bread crust. The aim of this study was to determine the use of amyloglucosidase for modulating the properties of the bread crust and increase its crispness. Increasing levels of enzyme were applied onto the surface of two different partially bake breads (thin and thick crust bread). Amyloglucosidase treatment affected significantly (P<0.05) the color of the crust and decreased the moisture content and water activity of the crusts. Mechanical properties were modified by amyloglucosidase, namely increasing levels of enzyme promoted a decrease in the force (Fm) required for crust rupture and an increase in the number of fracture events (Nwr) related to crispy products. Crust microstructure analysis confirmed that enzymatic treatment caused changes in the bread crust structure, leading to a disruption of the structure, by removing the starchy layer that covered the granules and increasing the number of voids, which agree with the texture fragility.Authors acknowledge the financial support of Spanish Ministry of Economy and Sustainability (Project AGL2011-23802), the European Regional Development Fund (FEDER), Generalitat Valenciana (Project Prometeo 2012/064) and the Consejo Superior de Investigaciones Cientificas (CSIC). R. Altamirano-Fortoul would like to thank her grant to CSIC. The authors also thank Forns Valencians S. A. (Spain) for supplying commercial frozen partially baked breads.Altamirano Fortoul, RDC.; Hernando Hernando, MI.; Molina Rosell, MC. (2014). Influence of amyloglucosidase in bread crust properties. 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Evaluating a query framework for software evolution data

With the steady advances in tooling to support software engineering, mastering all the features of modern IDEs, version control systems, and project trackers is becoming increasingly difficult. Answering even the most common developer questions can be surprisingly tedious and difficult. In this paper we present a user study with 35 subjects to evaluate our quasi-natural language interface that provides access to various facets of the evolution of a software system but requires almost zero learning effort. Our approach is tightly woven into the Eclipse IDE and allows developers to answer questions related to source code, development history, or bug and issue management. The results of our evaluation show that our query interface can outperform classical software engineering tools in terms of correctness, while yielding significant time savings to its users and greatly advancing the state of the art in terms of usability and learnability

Amido resistente e suas propriedades físico-químicas Resistant starch and its physicochemical properties

A partir da década de 80, começou a ser observado que uma fração do amido escapava da digestão no intestino delgado e chegava ao cólon, onde servia de substrato para a flora bacteriana. Essa fração foi denominada amido resistente e, a partir de então, constatou-se que determinados efeitos fisiológicos, inicialmente atribuídos às fibras alimentares, poderiam também ser atribuídos ao amido resistente. Vários fatores podem estar envolvidos na sua formação e eles, por sua vez, afetam a sua resposta fisiológica. Deste modo, torna-se importante o conhecimento dos aspectos físico-químicos envolvidos na formação do amido resistente.<br>Since the 1980s, it has been observed that a starch fraction was not digested in the small intestine, reaching the colon as a substrate for the bacterial flora. This fraction was called resistant starch and, from this time on, it was noticed that certain physiological effects, initially attributed to the dietary fiber, could also be attributed to the resistant starch. Several factors can be involved in its formation, and they, in turn, affect its physiological response. Therefore, the knowledge on the physicochemical aspects involved in the formation of the resistant starch becomes important