Proteolysis in model portuguese cheeses: Effects of rennet and starter culture

To shed further light onto the mechanisms of proteolysis that prevail throughout ripening of Portuguese cheeses, model cheeses were manufactured from bovine milk, following as much as possible traditional manufacture practices – using either animal or plant rennet. The individual role upon proteolysis of two (wild) strains of lactic acid bacteria – viz. Lactococcus lactis and Lactobacillus brevis, which are normally found to high viable numbers in said cheeses, was also considered, either as single or mixed cultures. Our experimental results confirmed the influence of rennet on the proteolysis extent, but not on proteolysis depth. On the other hand, the aforementioned strains clearly improved release of medium- and small-sized peptides, and contributed as well to the free amino acid pool in cheese

Three-dimensional scanning system based on a low-cost infrared sensor

Nowadays, with the availability of 3D printers, the scanners for objects are becoming increasingly present since they allow to replicate objects by 3D printing, especially for small scale sizes. However, the majority of these technologies are expensive, due to the complexity of this task. Therefore, this work presents a prototype of a low-cost 3D scanning system for small objects using a point cloud to stereolithography approach where it was already validated in simulation in previous work. This concept has a restriction that the objects must have a uniform shape, i.e, without discontinuities. The architecture is composed of two stepper motors, due to their precision, a rotating plate to allow 360 degrees scans and another rotating structure that allows the infrared distance sensor to scan the object from bottom to top (90 degrees). The prThis work has been supported by FCT - Fundação para a Ciência e Tecnologia within the Project Scope: UIDB/05757/2020. The project that gave rise to these results received the support of a fellowship from ”la Caixa” Foundation (ID 100010434). The fellowship code is LCF/BQ/DI20/11780028.info:eu-repo/semantics/publishedVersio

Effect of particle size upon the extent of extraction of antioxidant power from the plants Agrimonia eupatoria, Salvia sp. and Satureja montana

The dependence of the extent of aqueous extraction of antioxidant compounds on particle size and contact time was studied for three important medicinal plants, that are commonly used in infusions: agrimony, sage and savoury. The effect of extraction time was dependent on the plant considered; however, ca. 5 min can be taken as the minimum period required to assure an acceptable degree of extraction of those compounds. As expected, a smaller particle size led to a higher extraction extents; a typical value of 0.2 mmis accordingly recommended. Chlorogenic acid was the dominant phenolic compound extracted from agrimony, whereas caffeic acid dominated in the case of sage or savoury. A mathematical model based on Fick’s law was developed from first principles, and its two parameters were suitably fitted to the experimental data generated – in attempts to predict the evolution of antioxidant capacity extracted during contact time, for each plant and each particle size

Influence of bacterial dynamics upon the final characteristics

The microbiological profile in raw milk cheeses is typically characterized by a multitude of microbial groups, with interactions among them throughout ripening that are not fully understood to date. Incidence of undesired microorganisms in raw cheesemaking milk, as is the case of either spoilage or even pathogenic ones, is a common trait in Portuguese traditional cheeses. Hence, they will likely contribute to the physicochemical changes occurring therein and, consequently, to the characteristics of the final product. In order to gain insight into their role, model cheese systems, manufactured as far as possible according to artisanal practices (except that the initial microbial load and biodiversity were controlled), were experimentally tested. Single contaminants, or a consortium thereof, were inoculated at two levels in sterilized raw ewe's milk, and duly combined with inocula containing one or two lactic acid bacteria normally found in those traditional cheeses. The physicochemical composition, organic acid profile, and evolution of both protein breakdown and rheology were monitored throughout a 60 d-ripening period. Modifications brought about within the cheese matrix as a result of microbial metabolism, especially those arising from the interaction between lactic acid bacteria and unwanted microorganisms, included the enhanced release of peptides and free amino acids, which in turn led to higher viscoelastic moduli. The final model cheeses could be well discriminated, based on the impact of the various inocula considered upon the levels of organic acids. Conversely, proteolysis and viscoelastic properties appeared to be essentially independent of the initial microflora.info:eu-repo/semantics/publishedVersio

Bovine whey proteins - overview on their main biological properties

Whey, a liquid by-product, is widely accepted to contain many valuable constituents. These include especially proteins that posses important nutritional and biological properties – particularly with regard to promotion of health, as well as prevention of diseases and health conditions. Antimicrobial and antiviral actions, immune system stimulation, anticarcinogenic activity and other metabolic features have indeed been associated with such whey proteins, as a-lactalbumin, b-lactoglobulin, lactoferrin, lactoperoxidase, and bovine serum albumin. The most important advances reported to date pertaining to biological properties of whey proteins are reviewed in this communication

In vitro fermentation of raffinose to unravel its potential as prebiotic ingredient

Supplementary data to this article can be found online athttps://doi.org/10.1016/j.lwt.2020.109322.Until now the prebiotic potential of pure trisaccharide raffinose on human health assessed through high-throughput sequencing remains poorly investigated. In this work, an in vitro model using human fecal inocula of two healthy volunteers (D1 and D2) was used to study the prebiotic potential of raffinose and compare it with the well-stablished and commercial prebiotic lactulose. The intestinal microbiota showed preference for raffinose as substrate showing the highest consumption value at 48h (96.0±0.9% D1 and 95.3±0.7% D2). The fermentation of raffinose decreased the medium pH, the ammonia concentration and the relative amount of Proteobacteria, while increasing the total production of lactate and short chain fatty acids (129.9±2.6mmol/L D1 and 179.6±0.6mmol/L D2), CO2 (10.8±0.8 mmol/Lmedium D1 and 5.2±0.3 mmol/Lmedium D2) and the relative amount of Bifidobacterium and Lactobacillus. This study suggests that raffinose holds potential functional properties for human health.CA an BBC acknowledge her grants (UMINHO/BPD/4/2019 and SFRH/BD/132324/2017) from Portuguese Foundation for Science andTechnology (FCT). The study receivedfinancial support from FCT underthe scope of the strategic funding of UID/BIO/04469/2020 unit;COMPETE 2020 (POCI-01-0145-FEDER-006684), through nationalfunds and where applicable co-financed by the FEDER, within thePT2020 Partnership Agreement; the Projects FoSynBio (POCI-01-0145-FEDER-029549) and NewFood–Food Technologies Valorization(NORTE-324 01-0246-FEDER-000043). The authors also acknowledgeBioTecNorte operation (NORTE-01-0145-FEDER-000004) funded bythe European Regional Development Fund under the scope ofNorte2020 -Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio

Designing a functional rice muffin formulated with prebiotic oligosaccharides and sugar reduction

Innovation of pastry products towards higher nutritional and commercial value remains a challenge to the growing field of healthy food. In this study, the prebiotic supplementation and sugar reduction were explored in a widely consumed pastry product with a low level of innovation. The prebiotic potential of commercial agave inulin and galacto-oligosaccharides (GOS) was evaluated and compared by an in vitro model using human fecal inocula. Rice muffins containing 100% of sugar or 75% of sugar supplemented with 0.8% GOS were produced and compared with commercial rice muffins regarding their physical and textural properties. GOS fermentation led to the highest production of lactate and short-chain fatty acids, besides the most significant reduction of the final pH value and of the ammonia and methane production. Inulin presented a higher selectivity towards Lactobacillaceae (51 ± 1% of all), while GOS are more efficient to stimulate Bifidobacteriaceae growth (65 ± 7% of all).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; COMPETE 2020 (POCI-01-0145-FEDER-006684), FoSynBio (POCI-01-0145-FEDER-029549) and NewFood (NORTE-01-0246-FEDER000043). CA and BBC acknowledge their grants (UMINHO/BPD/4/2019 and SFRH/BD/132324/2017) from FCT. RM acknowledges the financial support to the Xunta de Galicia and FEDER by the project (EDD431B 2019/01).info:eu-repo/semantics/publishedVersio

Conflict and mediation in higher education: a portuguese case

O presente artigo aborda o conflito e mediação nas instituições de ensino superior. Desenvolveu-se um estudo descritivo de corte transversal aplicando um questionário na plataforma Google Forms com os objetivos de conhecer a opinião dos estudantes acerca da existência de conflitos ‒e a forma como estes podem ser resolvidos‒ numa instituição de ensino superior do norte de Portugal, de descrever a tipologia de conflito mais prevalente e de identificar as estratégias de resolução de conflitos mais utilizadas. Uma amostra de 185 estudantes identificou os conflitos entre estudantes e entre estudantes e professores como os mais prevalentes. Os conflitos foram resolvidos maioritariamente com a ajuda de amigos ou não foram resolvidos.This article addresses conflict and mediation in higher education institutions. A crosssectional descriptive study was developed by applying a questionnaire on the Google Forms platform aiming to find out the students' opinions about the existence of conflicts and how they can be resolved in a higher education institution in the north of Portugal, to describe the most prevalent conflict typology and to identify the most used conflict resolution strategies. A sample of 185 students identified conflicts between students and between students and teachers as the most prevalent. Conflicts were mostly solved with the help of friends or were not solved at all.info:eu-repo/semantics/publishedVersio

Diet of mid-Atlantic Sowerby’s beaked whales Mesoplodon bidens

Copyright © 2011 Elsevier Ltd. All rights reserved.The first mid-Atlantic diet of Mesoplodon beaked whales is presented, from ten Sowerby's Mesoplodon bidens stranded in the Azores region between 2002 and 2009. This doubles the worldwide number of stomachs sampled, and reveals new feeding habits for this species. The mean number of prey items per stomach was 85±89 (range: 12–238), with fish accounting for 99.3% and cephalopods contributing less than 1% of total prey. Fish otoliths from 15 families and cephalopod lower mandibles from three families were identified, representing 22 taxa. The diet consisted mainly of small mid-water fish, the most numerous being Diaphus sp., Lampanyctus sp. and Melamphaidae species. Myctophids were present in all stranded individuals, followed by Diretmidae, Melamphaidae and Opisthoproctus soleatus, while the remaining fish species were scarce or single occurrences. Consistency of diet in four different years reveals a divergence from all previous records in continental areas, where mainly neritic and shelf-break benthopelagic fish species have been reported. Mid-Atlantic Sowerby's beaked whales' showed dietary plasticity, feeding on the most abundant mid-water groups occurring between 0 and750 m. Trophic level from prey numerical frequency was estimated at 4.4±0.46

Oxidative stress involving changes in Nrf2 and ER stress in early stages of Alzheimer's disease

AbstractOxidative stress and endoplasmic reticulum (ER) stress have been associated with Alzheimer's disease (AD) progression. In this study we analyzed whether oxidative stress involving changes in Nrf2 and ER stress may constitute early events in AD pathogenesis by using human peripheral blood cells and an AD transgenic mouse model at different disease stages. Increased oxidative stress and increased phosphorylated Nrf2 (p(Ser40)Nrf2) were observed in human peripheral blood mononuclear cells (PBMCs) isolated from individuals with mild cognitive impairment (MCI). Moreover, we observed impaired ER Ca2+ homeostasis and increased ER stress markers in PBMCs from MCI individuals and mild AD patients. Evidence of early oxidative stress defense mechanisms in AD was substantiated by increased p(Ser40)Nrf2 in 3month-old 3xTg-AD male mice PBMCs, and also with increased nuclear Nrf2 levels in brain cortex. However, SOD1 protein levels were decreased in human MCI PBMCs and in 3xTg-AD mice brain cortex; the latter further correlated with reduced SOD1 mRNA levels. Increased ER stress was also detected in the brain cortex of young female and old male 3xTg-AD mice. We demonstrate oxidative stress and early Nrf2 activation in AD human and mouse models, which fails to regulate some of its targets, leading to repressed expression of antioxidant defenses (e.g., SOD-1), and extending to ER stress. Results suggest markers of prodromal AD linked to oxidative stress associated with Nrf2 activation and ER stress that may be followed in human peripheral blood mononuclear cells