Moderate electric fields effects on whey protein´s structure, interactions and gelation

São Paulo School of Advanced Sciences on Reverse Engineering of Processed Foods[Excerpt] Proteins are important food constituents with a high nutritional and functional value. They are one of the food constituents most affected by heat, causing their unfolding, aggregation and gelation. Ohmic heating’s potential to improve the quality of foodstuffs have been demonstrated due to its uniform and fast heating, together with its presumed moderate electric field (MEF) related effects. The electric effects on foodstuffs, and particularly on proteins, are not yet fully disclosed and understood. [...]This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684), and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. The authors Rui M. Rodrigues, Ricardo N. Pereira, also thank to FCT their financial grants with SFRH/BD/110723/2015, SFRH/BPD/81887/2011, respectively.info:eu-repo/semantics/publishedVersio

Cold gel-like emulsions of lactoferrin subjected to ohmic heating

Ohmic heating is a technique that has gained increasing attention because of its capacity to produce uniform heating, and claimed electrical influence on the functional and technological properties of treated protein dispersions. The aim of this work was to evaluate the influence of ohmic heating on the properties of cold gel-like emulsions, comparing them with those obtained by conventional heating. The effect of ohmic and conventional heating on physical and structural properties of lactoferrin was also addressed. Ohmic heating treatment resulted in less pronounced aggregation of lactoferrin, when compared to conventional heating. An increase of particle size, turbidity, intrinsic and extrinsic fluorescence values and a decrease of dichroic signal after heat treatment indicated an increase of protein interactions. Emulsions produced from heat-treated lactoferrin showed gel-like behavior which was related to the emulsifying capacity of lactoferrin, combined with the emulsification method and the heat pre-treatment applied to the protein. Rheological and microstructural properties were intrinsically related to the heat treatment of the protein since ohmic heating produced gel-like emulsions with a less rigid structure. These emulsions could be interesting for food applications containing heat-sensitive ingredients.Authors would like to thank National Council for Scientific and Technological Development (CNPq) for the PhD fellowship (140271/ 2014-7) and for the research grant (307168/2016-6). This study was also supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/ 04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded byEuropean Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Ricardo N. Pereira gratefully acknowledge to FCT the financial grant with reference SFRH/BPD/81887/2011. We also acknowledge Synlait Milk Ltd. for the donation of lactoferrin samples.info:eu-repo/semantics/publishedVersio

Ohmic heating affecting lactoferrin properties and influencing on production of cold, gel-like emulsions

São Paulo School of Advanced Sciences on Reverse Engineering of Processed Foods[Excerpt] Proteins when heated tend to unfold and aggregate. Ohmic heating is a technique that has gained increasing attention because of its uniform heating, and claimed influence on the functional and technological properties of protein dispersions once heated through this technology. [...]Authors would like to thank National Council for Scientific and Technological Development (CNPq) for the PhD fellowship (140271/2014-7) and for the research grant (305477/2012-9 and 479459/2012-6). This study was also supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Ricardo N. Pereira gratefully acknowledge to FCT the financial grant with reference SFRH/BPD/81887/2011.info:eu-repo/semantics/publishedVersio

Electric field effects on β-lactoglobulin thermal unfolding as a function of pH Impact on protein functionality

The presence of moderate electric fields (MEF) during ohmic heating (OH) treatment of whey protein systems have demonstrated potential to change physicochemical and functional properties, like aggregation rate and extension or viscoelastic behaviour. However, the specific action of MEF upon the molecular structure of proteins, particularly during thermal processing has yet to be clarified. The effects of MEF in pure fractions of -lactoglobulin (β-lg) under non-aggregating conditions (low concentration and ionic strength), were investigated in this work. Protein samples were identically heat-treated through conventional and OH methods and at different pH values. β-lg's structural features were characterized by evaluation of secondary structure distribution and local conformational changes using techniques such as circular dichroism, intrinsic and extrinsic fluorescence and free thiol groups reactivity. It was confirmed that MEF affects β-lg upon thermal unfolding, resulting in distinctive structural features, surface hydrophobicity and SH reactivity. The mechanism of action is probably related with the molecular motion induced by the oscillating electric field and is more pronounced at neutral pH, where β-lg is more susceptible to thermal structural changes. These results contribute to a better understanding of OH processing and its effects in food matrices reinforce the possibility of using MEF as a toll to change protein functionality. Industrial relevance Ohmic heating is an emerging technology and is being established as reference method for processing protein-rich food such as dairy and egg products. Non-thermal effects of the applied electric fields during ohmic heating have been addressed but few works deal with their real impact in structural and molecular properties of food proteins with high biological value. In this work demonstrated that the presence of an electric field during ohmic heating processing influences structural aspects of beta-lactoglobulin. This knowledge plays an important role on process design (i.e. pasteurization binomials and fouling control) and product quality because these proteins play an essential role in food's nutritional and organoleptic properties, as well as on functionality, allergenicity and stability aspects.FCT -Fuel Cell Technologies Program(NORTE-01-0145-FEDER-000004)info:eu-repo/semantics/publishedVersio

Fatal Disseminated Paracoccidioidomycosis In A Two-year-old Child.

A two year-old female child was admitted at the Pediatric Intensive Care Unit in a septic shock associated with a lymphoproliferative syndrome, with history of fever, adynamia and weight loss during the last two months. On admission, the main clinical and laboratory manifestations were: pallor, jaundice, disseminated enlarged lymph nodes, hepatosplenomegaly, crusted warts on face, anemia, eosinophilia, thrombocytopenia, increased direct and indirect bilirubin, alkaline phosphatase, and gammaglutamyl transpeptidase. A parenteral administration of fluids, dobutamine and mechanical ventilation was started, without improvement of the clinical conditions. A direct examination of exsudate collected from cervical lymph node revealed numerous oval-to-around cells with multiple budding, like a pilot wheel cell, suggesting Paracoccidioides brasiliensis. Even though treatment with intravenous sulfamethoxazole-trimethoprine was soon started, the child died 36 hours after hospital admission. Disseminated paracoccidioidomycosis was confirmed in the autopsy. This is the youngest case of paracoccidioidomycosis in children reported in the literature.4637-

Ohmic heating as an innovative approach for the production of keratin films

Ohmic heating is a thermal processing method based on the application of electric fields directly into a semi-conductive medium. In this study, we explored for the first time the use of ohmic heating to obtain keratin films. The properties of the films prepared by ohmic heating and conventional heating were evaluated and compared under similar thermal profiles. A lower increase in free thiols' concentration was obtained for the keratin solutions and keratin films submitted to ohmic heating (16% increase for the keratin solution extracted from virgin hair, pHâ¯9, submitted to ohmic heating and 23% when submitted to conventional heating). Significant differences in the swelling results were observed for the films prepared with keratin extracted from virgin hair, with a swelling decrease in about 55% for the films prepared by ohmic heating. Generally, the keratin films obtained by ohmic heating showed distinct properties comparatively to the films produced by conventional methods. The application of a fusion protein on the keratin films demonstrated their capacity to be used as substitutes to hair fibers when evaluating the potential of new cosmetic products. This work suggests that ohmic heating show potential to tailor keratin films properties depending on an intended application or functionality.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Ana Tinoco and Rui M. Rodrigues thanks FCT for funding the scholarships with the references SFRH/BD/114035/2015 and SFRH/BD/110723/2015, respectively.info:eu-repo/semantics/publishedVersio

First in situ observations of soft bottom megafauna from the Cascais Canyon head

We report the first in situ observations of soft bottom megafauna from the Cascais Canyon head. Observations were collected opportunistically during three technical dives with the ROV Luso between 460-805 m at two locations distanced 1,230 m. The habitats were clas-sified as upper bathyal fine mud. The soft bottom fauna was dominated by burrows of Nephrops norvegicus reaching up to 2.9 burrows/m2, a common habitat along the Portu-guese continental margin. To our knowledge, densities are the highest ever reported for depths below 300 m. The ichthyofauna at the upper Cascais Canyon is a mixture of lower shelf and upper bathyal species, including Phycis blennoides, Scyliorhynus canicula, Coe-lorhynchus labiatus/occa and Chimaera monstrosa. Bait release attracted Myxine glutinosa. Surveys in other geological settings of the Cascays Canyon are required to understand more comprehensively the diversity of its sessile and vagile biodiversity

Solubilization and hydrolysis of porcine coagulated blood protein using sub-critical solvent extraction

Pork represents a major fraction of the meat consumed worldwide but only 30% of the blood generated in slaughterhouses is re-used as raw material for food and feed. Innovative technologies and efficient processing strategies capable of generating added-value products from it are now attracting attention. In this study, the hydrolysis of porcine coagulated blood using sub-critical solvent extraction was investigated. Biomass was hydrolyzed using different temperatures (120–210 °C), applying only water (sub-critical water; SCW) or water with a low concentration of alkali (0.1 mol L−1 NaOH) and different reaction times (30–90 min). Resultant hydrolysates were analyzed for crude and soluble protein, peptide profile, and bioactivity by combining protein quantification, antioxidant activity, and fast protein liquid chromatography measurements. Results showed that increasing temperature increases the degree of hydrolysis and that the addition of NaOH enhances the solubilization of peptides with high molecular weights. Also, hydrolysates showed interesting antioxidant activity, being 60 min the time of reaction with best antioxidant activity. Nevertheless, using only water (SCW) as solvent, without chemical additives, allows the delivering of interesting protein-based bioactive fractions. Sub-critical solvent treatment of porcine blood resulted in added-value fractions with potential bioactivities through a simple and environmentally friendly process.info:eu-repo/semantics/publishedVersio

Design of β-lactoglobulin nanostructures for encapsulation and controlled release of riboflavin in the gastrointestinal tract

Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Bovine β-lactoglobulin (β-Lg) is a globular protein from milk and the major component of whey proteins (ca. 50 % of its protein content). It is a food-grade and Generally Recognized As Safe (GRAS) material, that have a high nutritional value and important biological and functional properties, particularly the capacity to form gels, which allows the formation of nanostructures that can be used to encapsulate nutraceuticals [1]. Besides, β-Lg is stable at low pH, and highly resistant to proteolytic degradation in the stomach. Riboflavin is an essential vitamin for the normal function of human brain and nervous system. However, this vitamin is poorly soluble in water and highly susceptible to light degradation, thus its encapsulation may represent a suitable solution to its protection, overcoming these issues [2]. This study aims at evaluating the ability of β-Lg food-grade nanostructures to encapsulate and control the release of riboflavin during the gastrointestinal (GI) passage. In this study, aqueous dispersions of β-Lg (1%) were accordingly produced, and formation of stable βLg nanostructures was ascertained at pH 6.0, after heating at 80 ºC for 10 min. The nanostructures formed were characterized in terms of size, surface charge and stability, morphology and association efficiency (AE) of riboflavin. Riboflavin-loaded nanostructures were then submitted to an in vitro GI model system, simulating the conditions of human GI tract (i.e. stomach, duodenum, jejunum and ileum) and their condition (e.g. temperature, pH, mixing, transit time, enzymes and other constituents such as bile). The experiments were carried out for 5 h, and the nanostructures were structurally characterized after each stage of digestion. [...]info:eu-repo/semantics/publishedVersio