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- Produtos lácteos fermentados à base de soro de leite de ovinoPublication . Gouveia, Luís Ricardo França; Pereira, Carlos José DiasO presente trabalho, foi desenvolvido no âmbito da unidade curricular de estágio profissionalizante do Mestrado em Engenharia Alimentar, na Escola Superior Agrária de Coimbra. A componente prática foi toda ela desenvolvida no departamento de lacticínios da instituição, durante sensivelmente 6 meses. Este trabalho apresenta uma solução alternativa para a recuperação de componentes à base de soro de leite de ovinos em fábricas de queijo. Esta solução foi apresentada devido ás fábricas não possuírem capacidade de concentrar o soro de leite, onde este, constitui uma quantidade significativa de subproduto na fabricação de queijos. Normalmente é utilizado diretamente para alimentação animal, ou é simplesmente descartado. Posto isto, por meio da ultrafiltração (UF), foram obtidos os concentrados líquidos de proteínas de soro de leite de ovinos (CLPS). Após a obtenção dos concentrados, foram criados dois tipos de produtos fermentados: um à base de grãos de kefir e outro à base de bactérias probióticas comerciais. As análises microbiológicas, físico-químicas (composição bruta, pH, acidez titulável) e propriedades reológicas dos produtos mencionados anteriormente, foram avaliadas e comparadas durante a fermentação e ao longo de 7º, 14º e 21º dias, em que foram armazenados numa câmara de refrigeração. Contudo, os resultados foram muito positivos e motivadores, visto que os produtos fermentados apresentaram quantidades adequadas de Lactococcus spp., Lactobacilus spp. (> 7 Log10 CFUmL-1) e leveduras (> 6 Log10 CFUmL-1). As propriedades reológicas dos produtos líquidos mantiveram-se estáveis durante os 21 dias de armazenamento em câmara de refrigeração. No entanto, os produtos do tipo gel apresentaram algumas variações na viscosidade após 14 dias, nos casos em que estavam presentes os grãos de kefir. Foi realizada uma análise sensorial após o 14º dia de armazenamento, onde os provadores tiveram preferência pelos fermentados do tipo liquido e preferiram o produto sem a adição de polpa de fruta. Palavras-chave: Ovinos, Soro de leite, Ultrafiltração, Kefir, Probióticos. ABSTRACT The present work was developed within the scope of the professional internship curricular unit from the Master in Food Engineering, at Escola Superior Agrária de Coimbra. The practical component was all developed in the dairy department of the institution, during approximately 6 months. This work presents an alternative solution for the recovery of whey based components from ovine in cheese factories. This solution was presented because the factories do not have the ability to concentrate whey, where it constitutes a significant amount of by- product in the cheeses manufacture. It is usually used directly for animal feed, or is simply discarded. Therefore, by means of ultrafiltration (UF), the ovine liquid whey proteins concentrates (LWPC) were obtained. After obtaining the concentrates, two types of fermented products were created: one based on kefir grains and another based on commercial probiotic bacteria. The microbiological, physical-chemical analysis (crude composition, pH, titratable acidity) and rheological properties of the aforementioned products were assessed and compared during the fermentation and throughout the 7th, 14th and 21st days, where they were stored in a refrigeration chamber. However, the results were very positive and motivating, since the fermented products had adequate amounts of Lactococcus spp., Lactobacilus spp. (> 7 Log10 CFUmL-1) and yeasts (> 6 Log10 CFUmL-1). The liquid products rheological properties remained stable during the 21 days of storage in the refrigeration chamber. However, the gel type products showed some variations in viscosity after 14 days in the cases where kefir grains were present. A sensorial analysis was performed after the 14th day of storage, where the tasters had preference for liquid type fermented and preferred the product without the addition of fruit pulp. Keywords: Ovines, Whey, Ultrafiltration, Kefir, Probiotics
- Measurement of charged-particle distributions sensitive to the underlying event in $ \sqrt{s}=13 $ TeV proton-proton collisions with the ATLAS detector at the LHCPublication . ATLAS collaboration (2839 authors); Aguilar-Saavedra, Juan Antonio; Amor Dos Santos, Susana Patricia; Anjos, Nuno; Araque, Juan Pedro; Carvalho, João; Castro, Nuno Filipe; Conde Muiño, Patricia; Da Cunha Sargedas De Sousa, Mario Jose; Fiolhais, Miguel; Galhardo, Bruno; Gomes, Agostinho; Gonçalo, Ricardo; Jorge, Pedro; Machado Miguens, Joana; Maio, Amélia; Maneira, José; Oleiro Seabra, Luis Filipe; Onofre, António; Pedro, Rute; Santos, Helena; Saraiva, João; Silva, José; Tavares Delgado, Ademar; Veloso, Filipe; Wolters, HelmutWe present charged-particle distributions sensitive to the underlying event, measured by the ATLAS detector in proton-proton collisions at a centre-of-mass energy of 13 TeV, in low-luminosity Large Hadron Collider fills corresponding to an integrated luminosity of 1.6 nb$^{−1}$. The distributions were constructed using charged particles with absolute pseudorapidity less than 2.5 and with transverse momentum greater than 500 MeV, in events with at least one such charged particle with transverse momentum above 1 GeV. These distributions characterise the angular distribution of energy and particle flows with respect to the charged particle with highest transverse momentum, as a function of both that momentum and of charged-particle multiplicity. The results have been corrected for detector effects and are compared to the predictions of various Monte Carlo event generators, experimentally establishing the level of underlying-event activity at LHC Run 2 energies and providing inputs for the development of event generator modelling. The current models in use for UE modelling typically describe this data to 5% accuracy, compared with data uncertainties of less than 1%.
- Measurement and QCD analysis of double-differential inclusive jet cross sections in pp collisions at $ \sqrt{s}=8 $ TeV and cross section ratios to 2.76 and 7 TeVPublication . CMS collaboration (2257 authors); Calpas, Betty; Nayak, Aruna; Bargassa, Pedrame; Beirão Da Cruz E Silva, Cristóvão; Di Francesco, Agostino; Faccioli, Pietro; Ferreira Parracho, Pedro Guilherme; Gallinaro, Michele; Hollar, Jonathan; Leonardo, Nuno; Lloret Iglesias, Lara; Rodrigues Antunes, Joao; Seixas, Joao; Toldaiev, Oleksii; Vadruccio, Daniele; Varela, Joao; Vischia, Pietro; David Tinoco Mendes, Andre; Silva, Pedro; Musella, Pasquale; Pela, JoaoA measurement of the double-differential inclusive jet cross section as a function of the jet transverse momentum pT and the absolute jet rapidity abs(y) is presented. Data from LHC proton-proton collisions at sqrt(s) = 8 TeV, corresponding to an integrated luminosity of 19.7 inverse femtobarns, have been collected with the CMS detector. Jets are reconstructed using the anti-kT clustering algorithm with a size parameter of 0.7 in a phase space region covering jet pT from 74 GeV up to 2.5 TeV and jet absolute rapidity up to abs(y) = 3.0. The low-pT jet range between 21 and 74 GeV is also studied up to abs(y) = 4.7, using a dedicated data sample corresponding to an integrated luminosity of 5.6 inverse picobarns. The measured jet cross section is corrected for detector effects and compared with the predictions from perturbative QCD at next-to-leading order (NLO) using various sets of parton distribution functions (PDF). Cross section ratios to the corresponding measurements performed at 2.76 and 7 TeV are presented. From the measured double-differential jet cross section, the value of the strong coupling constant evaluated at the Z mass is alpha[S(M[Z]) = 0.1164 +0.0060 -0.0043, where the errors include the PDF, scale, nonperturbative effects and experimental uncertainties, using the CT10 NLO PDFs. Improved constraints on PDFs based on the inclusive jet cross section measurement are presented.