Rancimat
Mostrando 1-12 de 54 artigos, teses e dissertações.
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1. Synthesis of Antioxidant Additive from Safflower Seed Oil
Several published studies have evaluated the problems associated with the utilization of biodiesel obtained from safflower (Carthamus tinctorius L.) oil due to the low oxidative stability, caused by the high content of unsaturated fatty acids. Thus, this study aimed at the extraction of safflower seed oil and its use as an unsaturation source to obtain a syn
J. Braz. Chem. Soc.. Publicado em: 2021-01
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2. EVALUATION OF THE RELATIVE PROTECTION FACTOR OF ROSEMARY EXTRACT IN BIODIESEL IN THE PRESENCE OF TRANSITION METAL IONS
Biodiesel contains unsaturated methyl esters making it susceptible to oxidation reaction. Among the factors that cause oxidative instability is the contamination by transition metal ions that in small quantities catalyze the oxidation reaction. The objective of this work was to evaluate the relative protection factor of rosemary extract, in biodiesel, in the
Quím. Nova. Publicado em: 2020-09
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3. APRESENTAÇÃO - História Antiga: Diferentes Perspectivas
Biodiesel is a suitable alternative to replace the petro-diesel. The biodiesel is formed by unsaturated esters easily degraded by interferences of oxygen, temperature, contact with metals or contaminants. The aim of this research was to investigate the biodiesel degradation process via 1H nuclear magnetic resonance (NMR) spectroscopy, observing the olefinic,
Rev. Bras. Hist.. Publicado em: 2020-08
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4. Evaluation of the Oxidation Degradation Process of Biodiesel via 1H NMR Spectroscopy
Biodiesel is a suitable alternative to replace the petro-diesel. The biodiesel is formed by unsaturated esters easily degraded by interferences of oxygen, temperature, contact with metals or contaminants. The aim of this research was to investigate the biodiesel degradation process via 1H nuclear magnetic resonance (NMR) spectroscopy, observing the olefinic,
J. Braz. Chem. Soc.. Publicado em: 2020-08
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5. Optimization of sunflower oil bleaching parameters: using Response Surface Methodology (RSM)
Abstract Bleaching is an important part of the oil refining process, in which pigments, impurities, traces of metals, and oxidative-molecular components of oils are removed. In this regard, the optimization of bleaching conditions can be effective to increase oil quality. In this study, de-gummed and neutralized sunflower oil was bleached at 80, 90, 100, 110
Food Sci. Technol. Publicado em: 2020-06
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6. EVALUATION OF ANTIOXIDANT ACTIVITY OF NATURAL EXTRACTS ON THE OXIDATIVE STABILITY OF COTTONSEED BIODIESEL
Abstract The objective of this study was to evaluate the antioxidant activity of the natural extracts catechin, curcumin and quercetin on the oxidative stability of methylic cottonseed oil biodiesel. The oxidative stability was evaluated using the Rancimat method (EN 14112) for biodiesel with 500, 1000, 1500, 2000 and 3000 ppm of additives, and compared with
Braz. J. Chem. Eng.. Publicado em: 30/09/2019
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7. Optimization of sunflower oil bleaching parameters: using Response Surface Methodology (RSM)
Abstract Bleaching is an important part of the oil refining process, in which pigments, impurities, traces of metals, and oxidative-molecular components of oils are removed. In this regard, the optimization of bleaching conditions can be effective to increase oil quality. In this study, de-gummed and neutralized sunflower oil was bleached at 80, 90, 100, 110
Food Sci. Technol. Publicado em: 30/09/2019
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8. Identification of Extra Virgin Olive Oils Modified by the Addition of Soybean Oil, Using Ion Chromatography
The modification of four extra virgin olive oils from different origins with refined soybean oil (SO), in the proportions of 0, 5, 10, 20 and 30% m/m, was studied using two approaches. First, the induction period (IP) was determined by Rancimat. In the second strategy, ion chromatography was used to quantify the formic and acetic acids, in their carboxylate
J. Braz. Chem. Soc.. Publicado em: 08/04/2019
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9. Effect of drying methods on long term storage of hazelnut
Abstract This research was conducted to determine the chemical traits of Ordu Levant hazelnuts that were dried with sun–drying [on concrete ground (CG), grass ground (GG)], or in drying machine (DM) during 24 months of storage (2014-2016) at 20-25 °C and 70-90% relative humidity. Drying process continued 39 h for CG and GG, and 23 h for DM. Sun–drying
Food Sci. Technol. Publicado em: 18/02/2019
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10. Quality parameters and thermogravimetric and oxidative profile of Muruci oil ( Byrsonima crassifolia L.) obtained by supercritical CO2
Abstract These researches aimed determine the quality parameters, the nutritional profile, and the thermogravimetric and oxidative behavior of Muruci (Byrsonima crassifolia L .) oil obtained by supercritical CO2 extraction. The results showed an average oil yield of 5.50%. The acidity and peroxide values show good quality and conservation standards, accordi
Food Sci. Technol. Publicado em: 2018-03
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11. Oxidative stability of soybean oil added to coffee husk extract (Coffea arabica L.) under accelerated storage conditions
Abstract Several plants have been studied as potential sources of natural antioxidants for use in the food industry, especially polyphenols. The aim of this study was to evaluate the effects of hydroalcoholic extract from coffee husk on the oxidative stability of soybean oil when stored in an oven. Samples were maintained at a temperature of 60 °C and their
Food Sci. Technol. Publicado em: 2017-12
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12. The Use of the Liquid from Cashew Nut Shells as an Antioxidant in Biodiesel
The influence of cashew nutshell liquid (CNSL) in the oxidative stability of biodiesels prepared from oils of soy, corn, canola and sunflower was studied using the Rancimat method. The induction periods at 110 ºC, without and with the addition of CNSL at concentrations of 0.1, 0.5 and 1.0% m/m, were determined and clearly show an important increase in the o
J. Braz. Chem. Soc.. Publicado em: 2017-05