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1.
Mar Drugs ; 21(7)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37504928

RESUMO

Bacterial and fungal infections are a challenging global problem due to the reported increasing resistance of pathogenic microorganisms to conventional antimicrobials. Nanomaterials are a promising strategy to fight infections caused by multidrug-resistant microbes. In this work, gold (Au@UP) and silver (Ag@UP) nanoparticles were produced for the first time by green synthesis using an aqueous extract of the invasive macroalgae Undaria pinnatifida (UP). The nanoparticles were characterized by a wide range of physicochemical techniques. Au@UP and Ag@UP demonstrated to be spherical and crystalline with an average size of 6.8 ± 1.0 nm and 14.1 ± 2.8 nm, respectively. Carbohydrates and proteins of the UP extract may participate in the synthesis and capping of the nanoparticles. The UP extract, Ag@UP, and Au@UP were assessed for their antimicrobial activity against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Candida auris. Ag@UP showed the highest antimicrobial activity with very low MIC and MBC values for all the tested bacteria, and Au@UP demonstrated to be very effective against biofilm-producing bacteria. The antifungal properties of both Ag@UP and Au@UP were remarkable, inhibiting hyphae formation. This study points towards a very promising biomedical exploitation of this invasive brown algae.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Alga Marinha , Undaria , Antibacterianos/farmacologia , Antibacterianos/química , Antioxidantes/farmacologia , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Ouro/química , Anti-Infecciosos/química , Bactérias , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana
2.
Molecules ; 28(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37110798

RESUMO

BACKGROUND: "FODMAPs" (fermentable-oligo-, di-, monosaccharides, and polyols) are a group of fermentable carbohydrates and polyols largely diffused in food products. Despite their beneficial effects as prebiotics, people affected by irritable bowel syndrome manifest symptoms when eating these carbohydrates. A low-FODMAP diet seems to be the only possible therapy proposed for symptom management. Bakery products are a common source of FODMAPs, whose pattern and total amount can be affected by their processing. This work aims at studying some of the technological parameters that can influence the FODMAPs pattern in bakery products during the production process. METHODS: high-performance anion exchange chromatography coupled to a pulsed amperometric detector (HPAEC-PAD) was used as a highly selective system for carbohydrates evaluation analyses on flours, doughs, and crackers. These analyses were performed using two different columns, the CarboPac PA200 and CarboPac PA1, which are selective for oligosaccharide and simple sugar separation, respectively. RESULTS: emmer and hemp flours were selected to prepare doughs as they contained low oligosaccharide content. Two different mixes of ferments were used at different times of fermentation to evaluate the best conditions to achieve low-FODMAP crackers. CONCLUSION: the proposed approach allows carbohydrate evaluation during crackers processing and permits the selection of opportune conditions to obtain low-FODMAP products.


Assuntos
Carboidratos , Síndrome do Intestino Irritável , Humanos , Oligossacarídeos , Monossacarídeos , Hexoses , Fermentação , Dissacarídeos
3.
ACS Appl Bio Mater ; 5(7): 3219-3229, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35729847

RESUMO

Biobased composites with peculiar properties offer an attractive route for producing environmentally friendly materials. The reinforcement for poly(butylene adipate-co-terephthalate) (PBAT), based on zein-titanium dioxide (TiO2) complex (ZTC) microparticles, is presented and used to produce composite filaments, successfully 3-dimensionally (3D) printed by fused deposition modeling (FDM). The outcome of ZTC addition, ranging from 5 to 40 wt %, on the thermo-mechanical properties of composite materials was analyzed. Results reveal that storage modulus increased with increasing the ZTC content, leading to a slight increase in the glass transition temperature. The creep compliance varies with the ZTC concentration, denoting a better resistance to deformation under constant stress conditions for composites with higher complex content. Scanning electron microscopy was used to assess the quality of interphase adhesion between PBAT and ZTC, showing good dispersion and distribution of complex microparticles in the polymer matrix. Infrared spectroscopy confirmed the formation of a valid interface due to the formation of hydrogen bonds between filler and polymer matrix. Preliminary tests on the biocompatibility of these materials were also performed, showing no cytotoxic effects on cell viability. Finally, the 3D printability of biobased composites was demonstrated by realizing complex structures with a commercial FDM printer.


Assuntos
Poliésteres , Polímeros , Excipientes , Microscopia Eletrônica de Varredura , Poliésteres/química , Polímeros/química , Impressão Tridimensional
4.
Food Chem ; 388: 132951, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35447585

RESUMO

The present review throws a spotlight on new and emerging food safety concerns in view of a well-established food allergen risk arising from global socio-economic changes, international trade, circular economy, environmental sustainability, and upcycling. Food culture globalization needs harmonization of regulations, technical specifications, and reference materials towards mutually recognised results. In parallel, routine laboratories require high-throughput reliable analytical strategies, even in-situ testing devices, to test both food products and food contact surfaces for residual allergens. Finally, the currently neglected safety issues associated to possible allergen exposure due to the newly proposed bio- and plant-based sustainable food contact materials require an in-depth investigation.


Assuntos
Alérgenos , Hipersensibilidade Alimentar , Comércio , Alimentos , Humanos , Internacionalidade
5.
Mar Drugs ; 20(3)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35323481

RESUMO

This study reports on the green and cost-efficient synthesis of gold nanoparticles from three different red algae extracts. The nanoparticles synthesized were fully characterized by UV-Vis spectroscopy, HRTEM, and Z-potential. Relevant components occurring in the extracts, such as polysaccharides or phenolic content, were assessed by analytical techniques such as spectrophotometric assays and liquid chromatography. Finally, the antioxidant, antitumoral, and anti-inflammatory potential of both the extracts and the gold nanoparticles synthesized were analyzed in order to determine a possible synergistic effect on the nanoparticles. The results obtained confirmed the obtainment of gold nanoparticles with significant potential as immunotherapeutic agents. The therapeutic potential of these nanoparticles could be higher than that of inert gold nanoparticles loaded with bioactive molecules since the former would allow for higher accumulation into the targeted tissue.


Assuntos
Antineoplásicos/administração & dosagem , Antioxidantes/administração & dosagem , Misturas Complexas/química , Ouro/administração & dosagem , Fatores Imunológicos/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Rodófitas/química , Antineoplásicos/química , Antioxidantes/química , Apoptose/efeitos dos fármacos , Linhagem Celular , Citocinas/metabolismo , Ouro/química , Humanos , Fatores Imunológicos/química , Nanopartículas Metálicas/química , Fenóis/análise , Fenóis/farmacologia , Polissacarídeos/análise , Polissacarídeos/farmacologia , Espécies Reativas de Oxigênio/metabolismo
6.
Mar Drugs ; 21(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36662193

RESUMO

Cancer still poses a global threat, since a lot of tumors remain untreatable despite all the available chemotherapeutic drugs, whose side effects, it must also be noted, still raise concerns. The antitumoral properties of marine seaweeds make them a potential source of new, less toxic, and more active antitumoral agents. Furthermore, these natural extracts can be combined with nanotechnology to increase their efficacy and improve targeting. In this work, a Codium tomentosum (CT) aqueous extract was employed for the green synthesis of gold nanoparticles (Au@CT). The complete characterization of Au@CT was performed by UV-Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Zeta potential, electron microscopy, X-ray powder diffraction (XRD), high-performance steric exclusion chromatography (HPSEC), and by the determination of their antioxidant capacity. The antiproliferative activity of Au@CT was then tested in hepatic (HEPG-2) and pancreatic (BxPC-3) cell lines. Their potential capacity as enhancers of gemcitabine, a drug frequently used to treat both types of tumors, was also tested. The activity of Au@CT was compared to the activity of the CT extract alone. A synergistic effect with gemcitabine was proven for HEPG-2. Our results showed that gold nanoparticles synthesized from seaweed extracts with antitumoral activity could be a good gemcitabine enhancer.


Assuntos
Clorófitas , Nanopartículas Metálicas , Neoplasias , Humanos , Gencitabina , Nanopartículas Metálicas/química , Ouro/farmacologia , Ouro/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Química Verde/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
7.
Food Res Int ; 139: 109959, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33509509

RESUMO

A recent European Regulation further restricted the use of bisphenol A in food-contact materials, reducing its limit of migration. However, all analytical systems of control are aimed at identifying and quantifying the molecules of this monomer without taking in consideration the possible presence of its oligomers, species originating from material degradation and able to follow an in-vivo hydrolysis providing bisphenol A generation. Thus, the presence of oligomers of polycarbonate deriving by unreacted species or polymer degradation can be considered a hidden source of several bisphenol A units, that remains outside the control of legislation and should be considered of high concern. This work was focused on the identification and the description of kinetics of release of different molecules migrating from polycarbonate food contact materials to simulants and to a model food sample such as melted chocolate. Analyses were performed by UHPLC system coupled to a Q-Exactive mass spectrometer. Targeted and untargeted analysis through data dependent acquisition mode allowed to detect the occurrence of several species deriving from polycarbonate, and permitted to investigate the polymer degradation pattern and explore the correlation of the recorded amounts of each product with age, hours of usage, and washing cycles of the plastic items.


Assuntos
Contaminação de Alimentos , Embalagem de Alimentos , Compostos Benzidrílicos , Contaminação de Alimentos/análise , Fenóis/análise
8.
Foods ; 10(1)2020 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-33375002

RESUMO

Green coffee parchment (GCP) is becoming interesting, due to the diffusion of wet processing in which coffee parchment is collected separately; it is one of the less studied coffee by-products, but it is reported to be rich in phenolic compounds and dietary fiber. The addition of GCP (355-500 µm) at 2 % to gluten-free breads was investigated in terms of physical properties (volume, moisture content, water activity, crumb grain, texture, and color), total antioxidant capacity (TAC) and total phenol content during three days of storage. Moreover, the effects of GCP on sensorial characteristics, 5-hydroxymethylfurfural (HMF), and oxidative stability was evaluated. From the sensorial analysis, bread with 2% addition resulted in being acceptable for consumers with no significant differences from the control, while 4% of GCP was discarded by consumers, as it resulted in being too bitter. Moreover, GCP at 2% addition did not modify volume, moisture content, and water activity. On the contrary, GCP deeply affected the color with a darker aspect that was appreciated by consumers. Regarding texture, 2% of GCP did not affect hardness, cohesiveness, and staling process during storage. Interestingly, 2% of GCP significantly improved the TAC and oxidative stability of the bread; in accordance with these results, 2% of GCP reduced the HMF content, thanks to its antioxidant compounds.

9.
Food Res Int ; 137: 109679, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33233256

RESUMO

Quartered Violetto artichokes were cooked with different treatments (boiling, steaming, sous vide and vacuum cooking) at the same cooking value at the thermal centre. Then, the physical (moisture content, texture and colour), histological and chemical (phenolic, 5-hydroxymethylfurfural (HMF) and furan content, total antioxidant capacity) features of bracts and hearts were assessed. A deeply modified microstructure was observed in boiled and steamed samples with an evident decrease in hardness both for bracts and hearts. Lightness of two anatomical parts was decreased by all the treatments (with the exception of sous vide bracts). The highest total colour difference was recorded for steamed samples, whereas the lowest was noted for sous vide samples. Steamed and sous vide artichoke exhibited the highest total phenolic content and total antioxidant capacity. Sous vide samples exhibited the highest concentrations of HMF, 2-furan-methanol and 2,4-dihydroxy-2,5-dimetyl-3(2H)-furanone, whereas the by-product 5-metylfuraldheide was only detected in the steamed product.


Assuntos
Cynara scolymus , Antioxidantes/análise , Culinária , Vapor , Vácuo
11.
Artigo em Inglês | MEDLINE | ID: mdl-30882280

RESUMO

Microalgal species growing in marine and aquaculture environments can be responsible for harmful events because of their ability to produce potent natural toxins that can accumulate in edible mollusc species. Their consumption can cause severe illness and even be lethal. The European Union provides comprehensive regulations covering various general food safety aspects to manage the risk of contamination in shellfish farms. Many analytical methods have been proposed to evaluate algal toxins presence in the environment and in food products, for conducting surveillance studies of the main molluscs production sites and, where necessary, immediate monitoring of possible contamination of shellfish. In this work, a one-year analytical surveillance study was carried out to verify the possible presence of algal biotoxins in molluscs from a Mediterranean breeding area. Water and molluscs were sampled from a district of the North-East coast of Sicily, consisting of a unique brackish ecosystem of two lakes connected to each other and to the sea by narrow canals. Water samples were collected to investigate phytoplankton i by microscope analysis to assess the presence of potentially toxin-producing species, such as Pseudo-nitzschia spp, Alexandrium spp and Gonyaulax spinifera, although the presence of toxic phytoplankton has never reached alert levels. Mussels and clams samples were submitted to analysis of paralytic shellfish poisoning toxins, amnesic shellfish poisoning toxins and lipophilic toxins by liquid chromatography-based methods Only a few yessotoxins were detected, having concentrations always below the regulation limits. An existing liquid chromatography-tandem mass spectrometry-based multiresidue method for lipophilic biotoxins was adopted and extended to cover emerging biotoxins such as cyclic imines. The performance of the analytical method for Gymnodimine A and Spirolide 13-desMeC was assessed, obtaining respective quantitation limits of 20 and 10 µg kg-1, a precision always lower than 13% and trueness in the 81-120% range. Method applicability was confirmed using certified materials and a naturally contaminated sample.


Assuntos
Monitoramento Ambiental , Inocuidade dos Alimentos , Toxinas Marinhas/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Animais , Análise de Alimentos , Itália , Região do Mediterrâneo , Frutos do Mar
12.
Mater Sci Eng C Mater Biol Appl ; 97: 498-509, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30678937

RESUMO

Marine bio-resources are being widely studied as an invaluable source of compounds with therapeutic applicability. In particular, macroalgae contain an extended variety of bioactive compounds with different structures and promising biological applications. In this work, Ulva lactuca L. (hereafter UL) was utilyzed for the synthesis of gold and silver nanoparticles. Full characterization by UV-Vis spectroscopy, TEM, HRTEM and STEM miscroscopies, Z Potential and FTIR spectroscopy was performed. The first time in the scientific literature, the composition of carbohydrates of UL extract and their changes observed after nanoparticles synthesis were explored in order to investigate their possible role in the biosynthetic process. The reducing power, total phenolic content and DPPH scavenging activity of UL extract, Au@UL and Ag@UL nanoparticles were determined. The effects of UL extract, Au@UL and Ag@UL were tested in vitro on the colon cancer cell lines HT-29 and Caco-2, on normal primary neonatal dermal fibroblast cell line PCS-201-010, as well as on normal colon cell line CCD-112CoN. Lastly, the apoptotic activity and cellular uptake evaluation was determined for Au@UL and Ag@UL.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Prata/química , Ulva/metabolismo , Antioxidantes/química , Apoptose/efeitos dos fármacos , Carboidratos/análise , Carboidratos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Humanos , Nanopartículas Metálicas/toxicidade , Microscopia Eletrônica de Transmissão , Fenóis/química , Extratos Vegetais/química , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier
13.
J Mass Spectrom ; 53(1): 83-90, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29053889

RESUMO

The interest towards "substances of emerging concerns" referred to objects intended to come into contact with food is recently growing. Such substances can be found in traces in simulants and in food products put in contact with plastic materials. In this context, it is important to set up analytical systems characterized by high sensitivity and to improve detection parameters to enhance signals. This work was aimed at optimizing a method based on UHPLC coupled to high resolution mass spectrometry to quantify the most common plastic additives, and able to detect the presence of polymers degradation products and coloring agents migrating from plastic re-usable containers. The optimization of mass spectrometric parameter settings for quantitative analysis of additives has been achieved by a chemometric approach, using a full factorial and d-optimal experimental designs, allowing to evaluate possible interactions between the investigated parameters. Results showed that the optimized method was characterized by improved features in terms of sensitivity respect to existing methods and was successfully applied to the analysis of a complex model food system such as chocolate put in contact with 14 polycarbonate tableware samples. A new procedure for sample pre-treatment was carried out and validated, showing high reliability. Results reported, for the first time, the presence of several molecules migrating to chocolate, in particular belonging to plastic additives, such Cyasorb UV5411, Tinuvin 234, Uvitex OB, and oligomers, whose amount was found to be correlated to age and degree of damage of the containers.


Assuntos
Chocolate/análise , Contaminação de Alimentos/análise , Plásticos/química , Poliésteres/química , Espectrometria de Massas em Tandem/métodos , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Embalagem de Alimentos , Utensílios Domésticos , Humanos , Limite de Detecção , Reprodutibilidade dos Testes
14.
Int J Food Sci Nutr ; 67(4): 391-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27045952

RESUMO

Pungency and red colour of Capsicum powders deteriorate during processing and storage, resulting in a decrease in market value. Two varieties of pepper with different pungencies were monitored for capsaicinoids, colour and furosine. Aliquots were stored at room and at low temperature during one year. At low temperature all indicators were stable in both varieties, while at room temperature, redness and capsacinoids decreased significantly, while furosine increased. High correlation was found between those markers. The more pungent variety exhibited higher stability in terms of all parameters. Differences observed suggest a potential protective effect exerted by capsaicinoids on powder stability. The decrease in capsaicinoids and redness accompanied by furosine increase showed a linkage between those markers never reported before. Considering that capsaicinoids and furosine occurrence have strong impact on the nutritional profile, the findings of this work show relevant changes in the nutritional value of chilli pepper powder after storage.


Assuntos
Capsaicina/análise , Capsicum/química , Qualidade dos Alimentos , Armazenamento de Alimentos , Lisina/análogos & derivados , Pigmentos Biológicos/análise , Especiarias/análise , Biomarcadores/análise , Capsaicina/análogos & derivados , Capsaicina/química , Temperatura Baixa , Inspeção de Alimentos , Frutas/química , Humanos , Itália , Lisina/análise , Lisina/química , Valor Nutritivo , Pigmentos Biológicos/química , Proteínas de Vegetais Comestíveis/análise , Proteínas de Vegetais Comestíveis/química , Estabilidade Proteica , Estereoisomerismo
15.
Talanta ; 147: 416-21, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26592627

RESUMO

The capabilities of desorption electrospray ionization-high resolution mass spectrometry (DESI-HRMS) were tested for screening the presence of some paralytic shellfish toxins in clams. A quick, easy, cheap, effective, rugged, and safe (QuEChERS) approach is proposed for sample clean-up. QuEChERS extraction was optimized by using a full factorial design followed by the multicriteria method of the desirability functions. Quantitation limits in the microgram per kilogram range proved reliability of the method for the detection of the investigated toxins in accordance to the rules laid down by European legislation. The optimized QuEChERS-DESI-HRMS based-method allowed for a rapid reliable screening of the investigated compounds at levels of interest, thus being useful for high-throughput analyses.


Assuntos
Toxinas Bacterianas/análise , Toxinas Bacterianas/isolamento & purificação , Bivalves/química , Fracionamento Químico/métodos , Análise de Alimentos/métodos , Segurança , Frutos do Mar , Animais , Análise de Alimentos/economia , Limite de Detecção , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray , Fatores de Tempo
16.
J Food Sci Technol ; 52(12): 8276-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26604404

RESUMO

Cold water steeping is reported to maximise tea health benefits, but requires long infusion time. In this work, the employment of a brief hot infusion step followed by ice addition was evaluated. The comparison of this innovative method with hot and cold steeping was investigated on green, black and oolong teas. Catechins, xanthines and gallic acid content, antioxidant power, total phenolics and colour analysis were evaluated. Hot infusion shown rapid extractive power, but relevant compound degradation. On the contrary, cold infusion extracted higher level of healthy molecules with slow kinetic. The innovative method achieved in short time similar properties of cold infusion in terms of antioxidant power. As for bioactive compounds, such as gallic acid and epigallocatechin gallate, highest values, about double than in hot infusion, were recorded for green and black teas. This steeping method may represent an alternative approach for industrial beverage preparation.

17.
Anal Bioanal Chem ; 407(26): 7917-24, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26297463

RESUMO

A new UHPLC-ESI-Orbitrap method for the identification and the quantitative determination of bisphenol A and some common additives employed in plastic manufacturing has been developed and validated. The method has been applied to evaluate the migration from 14 samples of tableware of different age and degree of surface damage, in both ethanol and isooctane (used as food simulants according to EU plastic regulation). Bisphenol A, three UV light absorbers, and one whitening agent were detected and quantified. Data were analyzed with the aim of exploring a possible correlation between bisphenol A and additives release, ageing, and surface integrity. A high correlation between age of samples, surface damage, and bisphenol A migration has been evaluated, while the release of additives was not correlated with other parameters. Obtained data showed for the first time that the release of bisphenol A seems to be more connected to ageing than to scratches and cracks occurrence. Graphical Abstract Bisphenol A and additives released by polycarbonate tableware: influence of ageing and surface damage.


Assuntos
Compostos Benzidrílicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Utensílios de Alimentação e Culinária , Espectrometria de Massas/métodos , Fenóis/análise , Plásticos/análise , Cimento de Policarboxilato/análise , Contaminação de Alimentos/análise , Substâncias Perigosas/análise , Humanos , Limite de Detecção
18.
J Chromatogr A ; 1372C: 133-144, 2014 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-25465011

RESUMO

Materials that come in contact with foods are potential sources of chemical food contamination. Consequently, characterization of their composition is of paramount importance considering the possible occurrence of several unknown molecules such as non-intentionally added substance (NIAS), residual monomers, degradation products, plastic additives and organic colorants. Previous studies concerning the characterization in terms of composition are focalized in the recognition of additives. To the best author's knowledge there are no scientific data about the composition of a plastic material in terms of colorants. In this work, an analytical method employing capillary ultra high-performance liquid chromatography and electrospray ionization quadrupole orbitrap high-resolution mass spectrometry (UHPLC-ESI Q-orbitrap) was exploited for characterization of polycarbonate for food contact material. Data-dependent experiments for targeted and untargeted analysis were employed after a total dissolution of polycarbonate samples and extraction of its components. The presence of common additives such as antioxidants and UV absorbers was confirmed by targeted analysis, while, the untargeted approach combined with the high mass accuracy of orbitrap technology allowed to identify for the first time some polycarbonate degradation products and the organic dyes effectively used for the coloration of plastic objects intended to come in contact with food. The present study shows the high potential of this technique in the field of material characterization aimed at food safety evaluation.

19.
Food Chem ; 165: 342-7, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25038685

RESUMO

In this work a comprehensive study on a new active packaging obtained by a hybrid organic-inorganic coating with antimicrobial properties was carried out. The packaging system based on polylactic acid was realised by sol-gel processing, employing tetraethoxysilane as a precursor of the inorganic phase and polyvinyl alcohol as the organic component, and incorporating natamycin as the active agent. Films with different organic-inorganic ratios (in a range between 1:19 and 1:4) were prepared, and the amount of antimycotic entrapped was found to be modulated by the sol composition, and was between 0.18 and 0.25mg/dm(2). FTIR microspectroscopic measurements were used to characterise the prepared coatings. The antifungal properties of the films were investigated against mould growth on the surface of commercial semi-soft cheese. The release of natamycin from the films to ethanol 50% (v/v) was studied by means of HPLC UV-DAD. The maximal level released was about 0.105 mg/dm(2), which is far below the value allowed by legislation.


Assuntos
Anti-Infecciosos/uso terapêutico , Antifúngicos/uso terapêutico , Embalagem de Alimentos/métodos , Ácido Láctico/química , Natamicina/uso terapêutico , Polímeros/química , Poliésteres , Polimetil Metacrilato
20.
Food Chem ; 140(4): 748-54, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23692762

RESUMO

Different markers for the assessment of thermal treatment entity of food products were investigated on a model bread prepared from wheat flour. Samples were submitted to different cooking procedures by combining three different times and temperatures, and employing two different ovens: a low-emissivity oven and a conventional one. The cook value index was calculated for each sample to evaluate the entity of the thermal treatment. Furosine, maltose:maltulose ratio, colour indexes (L, a, b) have been evaluated in all samples. Furosine has been quantified by capillary electrophoresis-mass spectrometry, maltose:maltulose ratio was determined by HPAEC-PAD, colour indexes were measured by spectrophotometer method. Values for weight loss during cooking and surface temperature have also been monitored. A statistical analysis showed good correlation between the cook value index and all the parameters evaluated. Low emissivity oven shown higher performances and lower energy consumption than conventional oven.


Assuntos
Pão/análise , Culinária/métodos , Farinha/análise , Triticum/química , Culinária/instrumentação , Temperatura Alta
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