671 research outputs found

    Evaluation of a chitosan-based edible film as carrier of natamycin to improve the storability of saloio cheese

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    The purpose of this study was to evaluate the effects of the application of chitosan coating containing natamycin on the physicochemical and microbial properties of semi-hard cheese. Three cheese groups were prepared: samples without coating, samples coated with chitosan and with chitosan containing 0.50 mg mL−1 of natamycin, whose minimum inhibitory concentration was previously determinated on cheese surface. Microbiological analyses showed that natamycin coated samples presented a decrease on moulds/yeasts of 1.1 log (CFU g−1) compared to control after 27 days of storage. Addition of natamycin also affected O2 and CO2 permeability, increasing from 7.12 to 7.68 × 10−15 g·(Pa s m)−1, and from 10.69 to 64.58 × 10−14 g·(Pa s m)−1, respectively. The diffusion coefficient values of natamycin from the film to phosphate buffered saline solution and to the cheese were 3.60 × 10−10 and 1.29 × 10−12 cm2 s−1, respectively. This study demonstrated that chitosan-based coating/films can be used as release system containing natamycin to create an additional hurdle for moulds/yeasts in cheese thus contributing to extend its shelf-life.Plan Galego de Investigación, Desenvolvemento e Innovación Tecnolóxica-Incite (Xunta de GaliciaFundação para a Ciência e a Tecnologia (FCT

    Oleogels for the development of healthier meat-based food products

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    Obesity is a disease that can be addressed through preemptive actions and behavioral changes like proper diet and exercise. In connection with obesity, cardiovascular disease can become an additional and severe problem. Scientific data regarding western diets, recons that dietary lipids account for over 35% of the daily caloric content of an individual's diet. Because of this it would be valuable to have alternatives with anti-obesogenic effects [1]. Another significant dietary factor in the prevention of obesity is a balanced omega-6/omega-3 ratio intake, that can be achieved through the consumption of enriched foods. Food innovation is driven by food products that contribute to improve health. These products are known as functional foods and they can be used strategically in order to avoid or battle the above-mentioned disorders. Functional oleogels were produced using enriched alpha-linolenic linseed oil with plant sterols (in hamburger production) and beeswax (in pate production) as oil gelators. Oleogels with 8 % (w/w) of gelator were used in both products as replaces of saturated fat. The range of fat replacement went from 25 to 75 % in hamburgers (H-25 and H-75) and 30 to 60 % in pate (P-30 and P-60). Tests with hamburgers showed that consumer acceptance and preference was directed towards the control samples. Nevertheless, the hamburgers samples with less amount of oleogel (H-25) were classified positively in both the acceptance and preference tests. Those same two sets of samples (control an H-25) showed similar textural characteristics. In the pate sensorial tests, the control sample was the much-liked one, however after data observation, the overall score for the P-30 sample still.Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462). Artur Martins is recipient of a fellowship supported by a doctoral advanced training (call NORTE-69-2015-15) funded by the European Social Fund under the scope of Norte2020 -Programa Operacional Regional do Norte. José M. Lorenzo, is a member of the MARCARNE network, funded by CYTED (ref. 116RT0503)info:eu-repo/semantics/publishedVersio

    Natamycin-loaded poly(n-isopropylacrylamide) nanohydrogels for smart edible packaging : development and characterization

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    The development of new formulations for antimicrobial agents release has attracted great attention due to the possibility of using such formulations in several applications (e.g. food packaging and surface treatments in biomedical devices). Smart packaging appears in the last years as one of the most promissory application to food packaging in order to enhance the capacity to maintain food quality and safety. Moreover, edible packaging, using edible and biodegradable biopolymers, has been stated as one of the promises in packaging science (e.g. fresh-cut products, cheese, fruits, fish). Based on this and in the fact that no work has been reported with the incorporation of smart nanohydrogels in edible packaging, a smart delivery device consisting in poly(N-isopropylacrylamide) nanohydrogels and polysaccharide- based films was developed. Polysaccharide-based films with and without the incorporation of natamycin-loaded poly(N-isopropylacrylamide) nanohydrogels were charactherized in terms of: transport (water vapour, oxygen and carbon dioxide permeabilities) and mechanical properties (tensile strength and elongation-at-break), opacity, water sensitivity (moisture content and contact angle) and thermal properties (differential scanning calorimetry - DSC and thermogravimetric analyses - TGA). Chemical interactions were studied by means of Fourier Transform Infrared Spectroscopy (FTIR) and scanning electron microscopy was used to verify the presence of nanohydrogel in the film matrix. [...

    Development of nanostructured lipid carriers based on oleogel using rhamnolipids as surfactant

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    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 the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Maria A. Azevedo (SFRH/BD/123364/2016) is the recipient of a fellowship from Fundação para a Ciência e Tecnologia (FCT, Portugal) and Artur J. Martins is recipient of a fellowship supported by a doctoral advanced training (call NORTE-69-2015-15) funded by the European Social Fund under the scope of Norte2020 -Programa Operacional Regional do Norteinfo:eu-repo/semantics/publishedVersio

    Active carboxymethylcellulose-based edible films: influence of free and encapsulated curcumin on films properties

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    Carboxymethylcellulose (CMC)-based films can act as a protective barrier in food surfaces and a carrier of bioactive compounds, such as curcumin. However, incorporating curcumin in hydrophilic matrixes can be a challenge, and new strategies need to be explored. In this work, CMC-based films containing free curcumin and curcumin-loaded nanohydrogels (composed of lactoferrin and glycomacropeptide) were produced and characterized. The incorporation of curcumin-loaded nanohydrogels showed a significant decrease in films thickness (from 0.0791 to 0.029 mm). Furthermore, the water vapor permeability of CMC-based films was significantly decreased (62%) by incorporating curcumin-loaded nanohydrogels in the films. The water affinitys properties (moisture, solubility, and contact angle) of films were also affected by incorporating encapsulated curcumin. The addition of nanohydrogels to CMC-based films reduced the tensile strength values from 16.46 to 9.87 MPa. Chemical interactions were analyzed using Fourier transform infrared spectroscopy. The release profile of curcumin from CMC-based films was evaluated at 25 °C using a hydrophilic food simulant and suggests that the release mechanism of the curcumin happens by Ficks diffusion and Case II transport. Results showed that protein-based nanohydrogels can be a good strategy for incorporating curcumin in edible films, highlighting their potential for use in food applications.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 the European Regional Development Fund under the scope of Norte2020—Programa Operacional Regional do Norte. Maria José Costa is recipient of a fellowship supported by a doctoral program (SFRH/BD/122897/2016) funded by the Portuguese Foundation for Science and Technology (FCT, POPH-QREN and FSE Portugal)info:eu-repo/semantics/publishedVersio

    Strategy towards replacing pork backfat with a linseed oleogel in frankfurter sausages and its evaluation on physicochemical, nutritional, and sensory characteristics

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    Different health institutions from western countries ha–ve recommended a diet higher in polyunsaturated fats, especially of the n-3 family. However, this is not a trivial task, especially for meat-processing sectors. The objective of this work was to assess the influence of replacing pork backfat with linseed oleogel on the main quality parameters of frankfurters. The frankfurters were formulated by the pork backfat replacement of 0% (control), 25% (SF-25), and 50% (SF-50), using a linseed oleogel gelled with beeswax. The determination of quality parameters (pH, colour, chemical composition, and texture parameters), the fatty acid profile, and the sensory evaluation was carried out for each batch. The fatty acid profile was substantially improved, and the saturated fatty acid (SFA) content was reduced from 35.15g/100g in control sausages to 33.95 and 32.34g/100 g in SF-25 and SF-50, respectively, and more balanced ratios n-6/n-3 were achieved. In addition, the sausages with linseed oleogel also decreased the cholesterol content from 25.08 mg/100 g in control sausages to 20.12 and 17.23 mg/100 g in SF-25 and SF-50, respectively. It may therefore be concluded that these innovative meat products are a healthier alternative. However, sensory parameters should be improved in order to increase consumer acceptability, and further research is needed.Artur Martins is the recipient of a fellowship supported by a doctoral advanced training (call NORTE-69-2015-15) funded by the European Social Fund under the scope of Norte2020—Programa Operacional Regional do Norte. Jose M. Lorenzo is a member of the HealthyMeat network, funded by CYTED (ref. 119RT0568). Thanks to GAIN (Axencia Galega de Innovación) for supporting this research (grant number IN607A2019/01)

    Response of vegetation to drought time-scales across global land biomes

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    We evaluated the response of the Earth land biomes to drought by correlating a drought indexwith three global indicators of vegetation activity and growth: vegetation indices from satellite imagery, tree-ring growth series, and Aboveground Net Primary Production (ANPP) records. Arid and humid biomes are both affected by drought, and we suggest that the persistence of thewater deficit (i.e., the drought time-scale) could be playing a key role in determining the sensitivity of land biomes to drought. We found that arid biomes respond to drought at short time-scales; that is, there is a rapid vegetation reaction as soon as water deficits below normal conditions occur. This may be due to the fact that plant species of arid regions havemechanisms allowing them to rapidly adapt to changing water availability. Humid biomes also respond to drought at short time-scales, but in this case the physiological mechanisms likely differ fromthose operating in arid biomes, as plants usually have a poor adaptability to water shortage. On the contrary, semiarid and subhumid biomes respond to drought at long time-scales, probably because plants are able to withstand water deficits, but they lack the rapid response of arid biomes to drought. These results are consistent among three vegetation parameters analyzed and across different land biomes, showing that the response of vegetation to drought depends on characteristic drought time-scales for each biome. Understanding the dominant time-scales at which drought most influences vegetation might help assessing the resistance and resilience of vegetation and improving our knowledge of vegetation vulnerability to climate change

    Hybrid gels: influence of water and oil phase on textural and rheological properties

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    The 19th Gums & Stabilisers for the Food Industry Conference: Hydrocolloid MultifunctionalityHybrid gels are biphasic systems formed by conjugating hydrogels and oleogels. The mixture of water-based and oil-based gels provides distinct and unique characteristics to hybrid gels, and based on the structurant molecules and mixture ratio used during their production, different textural and rheological properties can be obtained. Hybrid gels remain a very recent topic concerning pharmaceutical and food applications and despite recent studies on the use of hybrid gels for controlled delivery of compounds (pharmaceutical applications) these structures are still under-studied in regard to their food application possibilities [1, 2]. To improve knowledge and expanding ways to use these systems, it is important to understand how these gels behave regarding textural and rheological properties. Also, the knowledge on their micro and nanostructure allows tailoring their properties and thus maximizing their applicability in foodstuffs. We report on how the combination of a beeswaxbased oleogel and a sodium alginate-based hydrogel influences the gel structural properties at macroscopic (rheological and textural), microscopic (optical microscopy) and molecular (Xray diffraction) levels. Different ratios of both hydrogel and oleogel were used in order to evaluate the hybrid gels’ behaviour in terms of morphological, textural, rheological and polymorphic properties. Differences regarding oleogel particles distribution in the hydrogel matrix were noticed with the increase of oleogel fraction. A more disarranged distribution of oleogel particles was observable for the 50:50 ratios of hydrogel and oleogel. X-ray diffraction data unveiled that once polycrystallinity is reached (in hybrid gels) these patterns remain persistent for all tested ratios. Oleogel showed d-spacings in the range of 3.74 to 8.04 Å. Hybrid gel samples (and hydrogel control) are semi-crystalline, displaying spacings ranging in intervals of d (001) 6.99 – 7.18 Å; d (002) 3.09 – 3.23 Å and d (003) 2.45 – 2.46 Å, respectively. The samples with increasing oleogel ratio revealed a firmness decrease and a consequent reduction of spreadability values. Consequently, is observed less adhesivity for these samples, due to a more pronounced disaggregated structure. For all hybrid gels a gellike behaviour (G´ > G´´) was observed. Results showed that it is possible to modify the hybrid gels’ rheological and textural behaviour by a controlled mixture ratio of oleogels and hydrogels. This opens the possibilities of food applications for this kind of systems.info:eu-repo/semantics/publishedVersio

    Prevalence, characteristics, and impact of adverse events in 34 Madrid hospitals. The ESHMAD study

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    Introduction: Adverse Events (AE) are one of the main problems in healthcare. Therefore, many policies have been developed worldwide to mitigate their im pact. The Patient Safety Incident Study in Hospitals in the Community of Madrid (ESHMAD) measures the results of them in the region. Methods: Cross-sectional study, conducted in May 2019, in hospitalised patients in 34 public hospitals using the Harvard Medical Practice Study methodology. A logistic regression model was carried out to study the association of the variables with the presence of AE, calibrated and adjusted by patient. Results: A total of 9975 patients were included, estimating a prevalence of AE of 11.9%. A higher risk of AE was observed in patients with surgical procedures (OR[CI95%]: 2.15[1.79 to 2.57], vs. absence), in Intensive Care Units (OR[CI95%]: 1.60[1.17 to 2.17], vs. Medical) and in hospitals of medium complexity (OR[CI95%]: 1.45[1.12 to 1.87], vs. low complexity). A 62.6% of AE increased the length of the stay or it was the cause of admission, and 46.9% of AE were considered prevent able. In 11.5% of patients with AE, they had contributed to their death. Conclusions: The prevalence of AE remains similar to the previously estimated one in studies developed with the same methodology. AE keep leading to longer hospital stays, contributing to patient's death, showing that it is necessary to put focus on patient safety again. A detailed analysis of these events has enabled the detection of specific areas for improvement according to the type of care, centre and patient
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