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| Registros recuperados: 33 | |
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| PEGO,MATHEUS F.F.; BIANCHI,MARIA LÚCIA; CARVALHO,JANAÍNA A.; VEIGA,TAIS R.L.A.. |
| Surface modification may lead activated carbon (AC) to take on different properties. This study aimed to promote surface modification of activated carbons using corona treatment (electrical discharge). In this study, powdered commercial activated carbon was used. Activated carbons were subjected to corona treatment at different exposure times (2, 5, 8 and 10 min) at 4.5 cm height from the source. To observe differences promoted by treatment, activated carbons were analyzed by acidity, surface functional groups, Fourier Transform Infrared Spectroscopy (FTIR), elemental analysis (CHN), proximate analysis and thermogravimetry. Corona treatment impacted surface chemistry of activated carbons. There was a trend of increasing surface acidity according to... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Chemical reactions; Electric discharge; Oxidation; Surface chemistry. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000100402 |
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| LAMUELA-RAVENTÓS,ROSA M; GIMENO,EVA; FITÓ,MONTSE; CASTELLOTE,ANA-ISABEL; COVAS,MARIBEL; DE LA TORRE-BORONAT,M. CARMEN; LÓPEZ-SABATER,M. CARMEN. |
| Phenolic compounds have shown to inhibit LDL oxidation in vitro and ex vivo; however, they are hydrosoluble compounds while LDL is a lipoprotein. Analysis of phenolic compounds in LDLs by HPLC is necessary to demonstrate their binding capacity to lipoproteins. We developed and validated a solid phase extraction method (SPE) that allowed us the purification of LDL samples and their analysis by HPLC. This methodology allowed us to demonstrate the in vitro binding capacity of tyrosol, one of the main phenolic compounds in olive oil, to LDL. In the intervention dietary study with volunteers, food rich in phenolic compounds affected LDL composition. Changes in LDL phenolics composition are not observed after the short-term ingestion of food rich in phenolic... |
| Tipo: Journal article |
Palavras-chave: Antioxidant; LDL; Olive oil; Oxidation; Phenol; Tyrosol. |
| Ano: 2004 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602004000200011 |
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| Vargas,Flávia Carolina; Arantes-Pereira,Lucas; Costa,Patrícia Argemira da; Melo,Mariza Pires de; Sobral,Paulo José do Amaral. |
| ABSTRACT Because processing and storage conditions affect several beef quality attributes, the food industry uses a variety of synthetic antioxidants. However, some synthetic antioxidants have been questioned regarding its safety, and thus the interest in using natural antioxidants in food products is increasing. This paper aimed at assessing leaf aqueous extracts of Rosemary (Rosmarinus officinalis Linnaeus) and Pitanga (Eugenia uniflora Linnaeus) as antioxidants in beef cold storage. After 48h storage, patties added of Rosemary leaf extracts showed increased pH. Patties added of Pitanga extracts had the lowest a* color values. Oxymyoglobin levels were significantly higher for Negative control, than for Pitanga treatment. The 10% extract addition... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Antioxidant; Myoglobin; Color; Oxidation; Lipid. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132016000100514 |
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| RAMÍREZ-ANAYA,Jessica del Pilar; MANZANO-HERNÁNDEZ,Ariana Jocelyn; TAPIA-CAMPOS,Ernesto; ALARCÓN-DOMÍNGUEZ,Karina; CASTAÑEDA-SAUCEDO,Ma Claudia. |
| Abstract Virgin oil from avocados (Persea americana Mill.) is obtained by mechanical processes after pulp malaxation at temperatures that minimize oxidation and improve separation. The objective of this study was to assess the effect of time (0, 20, 30, 40, 60, 120 and 180 min) and temperature (40 and 50 °C) conditions during pulp malaxation on extraction yield, nutritional value (normalized fatty acid profile) and specific extintion (K232 and K270) of virgin oil extracted under laboratory conditions from avocados cultivated in southern Jalisco, Mexico. When pulp was malaxated for 120 min at 40 and 50 °C, a larger proportion of oil was extracted (82.9 ± 0.3% and 80.2 ± 0.8%, respectively). We observed that the normalized percentage of the fatty acids... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Essential fatty acid; Fatty acids; Linoleic:palmitic ratio; Oil yield; Oxidation. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612018000200223 |
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| Del Ré,Patrícia Vieira; Jorge,Neuza. |
| Studies have been carried out in order to increase the stability of vegetable oils due to economic and health protection reasons. There is a growing interest in the addition of natural antioxidants; especially herbs and spices. For this reason, this study aimed at evaluating the antioxidant potential of the oleoresins of oregano, basil, and thyme, as well as their behavior when applied to soybean oil under various concentrations. Firstly, the antioxidant activity was determined by the β-carotene/linoleic acid system and by the quantification of total phenolic compounds. Next, different concentrations of oleoresins (500 to 3000 mg.kg-1) were added to the soybean oil, and its antioxidant potential was analyzed using the oxidative stability through a Rancimat... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Spice extracts; Oxidation; Induction period. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612011000400021 |
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| Mendes,Nathalia da Silva Rodrigues; Gomes-Ruffi,Cristiane Rodrigues; Lage,Moacir Evandro; Becker,Fernanda Salamoni; Melo,Adriane Alexandre Machado de; Silva,Flávio Alves da; Damiani,Clarissa. |
| Food industries have been concerned about managing the waste generated by their production processes in order to minimize environmental impacts and also about the development of formulations with different and innovative ingredients such as fruits from the Brazilian savanna. Seeking to meet the expectations of consumers who desire healthy and practical products, this study aimed to evaluate the oxidative stability and the variations in chemical composition and antioxidant potential of cereal bars made with fruit peels and baru nuts packaged in different types of packaging. The bars formulated were packed in four different types of packaging: laminated without vacuum (LWV), transparent without vacuum (TWV), transparent under vacuum (TV), and laminated under... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Waste recovery; Savanna; Oxidation. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612013000400019 |
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| VIEIRA,Thais M. F. S.; REGITANO-DARCE,Marisa A. B.. |
| The effects of microwave heating on the oxidative stability of refined canola, corn and soybean oils were determined by absorptivity in the UV spectrum and by chemical analysis (peroxide and acid values). Samples were heated in a microwave oven (800 W, 2,450 MHz) for 0 to 36 min. Microwave heating produced oxidative degradation in the three oils. Absorptivity at 232 and 270 nm increased gradually with an increase in microwave exposure time (0-36 min) for canola, corn and soybean oils. Values of absorptivity at 232 nm increased from 4.812, 3.568 and 4.183 to 10.579, 12.874 and 15.950 after 36 min of heating canola, corn and soybean oil, respectively. The absorptivity at 232nm, due to the formation of conjugated dienes, was a good index for measuring the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Canola oil; Corn oil; Soybean oil; Microwave; Stability; UV/spectrophotometry; Oxidation. |
| Ano: 1998 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20611998000400015 |
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| Perlo,Flavia; Fabre,Romina; Bonato,Patricia; Jenko,Carolina; Tisocco,Osvaldo; Teira,Gustavo. |
| ABSTRACT: There is an increasing consumer demand to avoid the use of synthetic additives like many antioxidants currently added to food. The objective of this study was to determine the effect of spraying ascorbic acid, rosemary extract and a combination of both on pork meat during refrigerated storage. Pork meat with antioxidants sprayed on the surface was packaged under vacuum and stored (4ºC, 45d). pH, color, lipid oxidation, total aerobic count, drip loss and moisture were evaluated during storage. Results suggested that surface application of rosemary extract and a combination of rosemary extract and ascorbic acid resulted in an effective delay of lipid oxidation of pork meat, without affecting pH, colour or water content during storage. No effect of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Natural antioxidants; Oxidation; Storage; Meat quality. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782018000400751 |
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| Zago,Gilberto Rogério; Gottardo,Franciele Maria; Bilibio,Denise; Freitas,Carla Patrícia; Bertol,Charise Dallazem; Dickel,Elci Lotar; Santos,Luciana Ruschel dos. |
| ABSTRACT: Pomegranate (Punica granatum L.) contains a high concentration of antioxidant and phenolic compounds. Pomegranate peel extracts at different concentrations were used as natural antioxidant to increased the lipid stability of fresh Tuscan sausages, comparing with sodium erythorbate (SE). Peels were subjected to ultrasound-assisted aqueous extraction and lyophilization. The extract was previously characterized throught phenol and flavonoids determination. The Tuscan Sausages were prepared, and color, pH, peroxides, and thiobarbituric acid reactive substances were assessed at 1, 15, and 30 days of storage, at a mean temperature of 5 ± 1 ºC and under a 12-hour light cycle/day. Sausages containing 0.05 and 0.1% of peel extract showed results similar... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Meat product; Lipid; Oxidation; Storage; Sensory analysis. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782020000400753 |
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| Morita, R; Jones, R. |
| The nitrifying bacteria were found to survive 24 weeks in the absence of ammonium without decreasing their number of cell size. Because H sub(2), CO, and CH sub(4) are present in the marine environment, these substrates were investigated as a possible source of the energy of maintenance for the nitrifying bacteria. super(14)CO and super(14)CH sub(4) were found to be oxidized by the nitrifiers. N-serve was found to inhibit the oxidation of CO. Using the nitrifiers' ability to oxide CO, a method for the determination of the nitrification rate was developed. The ability of nitrifiers to oxidize CO may play a significant role in the cycling of CO sub(2) in the marine environment. Whether CO and CH sub(4) oxidation play a role in the survival of nitrifiers in... |
| Tipo: Text |
Palavras-chave: Methane; Carbon dioxide; Survival; Bacteria; Nitrification; Nitrogen cycle; Oxidation; Carbon cycle; Biogeochemistry; Metabolism. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-975.pdf |
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| Genot, Claude; Eymard, Sylvie; Viau, Michèle. |
| Increase the consumption of long-chain omega 3 polyunsaturated fatty acids (LC ω3 PUFA) is highly recommended for their health benefits. However, these fatty acids are very prone to oxidation, which can impair sensory, nutritional and functional properties of foods. In this paper the various ways that increase LC ω3 PUFA stability during processing and storage of food products are reviewed. To efficiently protect LC ω3 PUFA during processing and storage of foods, a combined strategy, taking into account both the matrix and the process should be undertaken. First the quality of the raw materials should be rigorously controlled by, for example, increasing contents of in situ antioxidants and decreasing length of storage. Then, during processing and storage... |
| Tipo: Text |
Palavras-chave: Oxidation; Lipids; Omega 3 polyunsaturated fatty acids; Antioxidants process; Formulation; Structure. |
| Ano: 2004 |
URL: https://archimer.ifremer.fr/doc/00480/59157/61786.pdf |
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| Passier, Hf; Dekkers, Mj. |
| Low-temperature magnetic properties of eastern Mediterranean sediments from a box-core have been investigated. This box-core contains the present-day oxic-suboxic boundary that is situated at the top of the relic of the youngest sapropel (S1). The upper half of sapropel S1 has been oxidized, and Fe oxides have precipitated in the oxidized sapropel. Zero-field-cooling (ZFC) and field-cooling (FC) saturation remanent magnetization (M-r; induced in a field of 2.5 T at 20 K after cooling from 300 K with or without the 2.5 T field) was measured during warming to 300 K. An M (r) imparted at room temperature (RTSIRM) was cycled to 20 K as well. The difference between ZFC and FC curves around the Verwey transition, as estimated by the parameter delta(FC)... |
| Tipo: Text |
Palavras-chave: Geochemistry; Low-temperature magnetism; Magnetite; Marine sediments; Oxidation; Sediment magnetism. |
| Ano: 2002 |
URL: https://archimer.ifremer.fr/doc/00223/33399/31887.pdf |
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| Le Gac, Pierre-yves; Broudin, Morgane; Roux, Gérard; Verdu, Jacques; Davies, Peter; Fayolle, Bruno. |
| Tensile properties and crack propagation properties, especially critical strain energy release rate in mode I, GIC, have been used to investigate fracture properties of elastomers and their relationships with microstructure. These investigations were mainly based on a series of comparisons: first, the behaviour of polychloroprene rubber (CR), undergoing stress hardening due to strain induced crystallization (SIC) and oxidative crosslinking (OCL) was compared with that of chlorinated polyethylene (CPE), which undergoes SIC but not OCL, and with a polyurethane based on hydroxyl terminated polybutadiene (PU) which undergoes OCL but not SIC. Comparisons were also made on CR between fracture behaviour at ambient temperature, where SIC occurs and at 100°C where... |
| Tipo: Text |
Palavras-chave: Fracture; Rubber; Oxidation. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00184/29546/27872.pdf |
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| Registros recuperados: 33 | |
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