The Experts below are selected from a list of 171 Experts worldwide ranked by ideXlab platform
Juan H. Ayala - One of the best experts on this subject based on the ideXlab platform.
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Optimization of an analytical methodology for the determination of alkyl- and methoxy-phenolic compounds by HS-SPME in biomass smoke
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Francisco J. Conde, Ana M. Afonso, Venerando González, Juan H. AyalaAbstract:A sampling and analysis method for the determination of 21 phenolic compounds in smoke samples from biomass combustion has been developed. The smoke is used to make Smoked Foods, following an artisanal procedure used in some parts of the Canary Islands. The sampling system consists of a Bravo H air sampler, two impingers, each one containing an aqueous solution of sodium hydroxide 0.1 mol L^−1, followed by a silica gel trap. The variables optimized to reach the best sampling conditions were volume of absorbent solution and sampling flow. Under the optimum conditions, 100 mL of absorbent solution of NaOH 0.10 mol L^−1 and 2 L min^−1 for the sampling flow, sampling efficiencies are higher than 80%. Analysis of phenolic compounds was carried out by headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography–mass spectrometry (GC-MS). Five different fiber coatings were employed in this study. By means of a central composite design, extraction time, salt concentration, and pH of the solution were optimized: 65-μm carbowax–divinylbenzene, extraction time 90 min, concentration in NaCl of 35% (m/v), and pH 2 yielded the highest response. Detection limits of phenol and their alkyl derivatives, guaiacol and eugenol, are between 1.13 and 4.60 ng mL^−1. 3-Methoxyphenol, 2,6-dimethoxyphenol, and vanillin have detection limits considerably higher. Good linearity ( R ^2≥0.98) was observed for all calibration curves in the established ranges. The reproducibility of the method (RSD, relative standard deviation) was found to oscillate between 7 and 18% (generally close or lower than 10%).
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Optimization of an analytical methodology for the determination of alkyl- and methoxy-phenolic compounds by HS-SPME in biomass smoke
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Francisco J. Conde, Ana M. Afonso, Venerando González, Juan H. AyalaAbstract:A sampling and analysis method for the determination of 21 phenolic compounds in smoke samples from biomass combustion has been developed. The smoke is used to make Smoked Foods, following an artisanal procedure used in some parts of the Canary Islands. The sampling system consists of a Bravo H air sampler, two impingers, each one containing an aqueous solution of sodium hydroxide 0.1 mol L^−1, followed by a silica gel trap. The variables optimized to reach the best sampling conditions were volume of absorbent solution and sampling flow. Under the optimum conditions, 100 mL of absorbent solution of NaOH 0.10 mol L^−1 and 2 L min^−1 for the sampling flow, sampling efficiencies are higher than 80%. Analysis of phenolic compounds was carried out by headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography–mass spectrometry (GC-MS). Five different fiber coatings were employed in this study. By means of a central composite design, extraction time, salt concentration, and pH of the solution were optimized: 65-μm carbowax–divinylbenzene, extraction time 90 min, concentration in NaCl of 35% (m/v), and pH 2 yielded the highest response. Detection limits of phenol and their alkyl derivatives, guaiacol and eugenol, are between 1.13 and 4.60 ng mL^−1. 3-Methoxyphenol, 2,6-dimethoxyphenol, and vanillin have detection limits considerably higher. Good linearity ( R ^2≥0.98) was observed for all calibration curves in the established ranges. The reproducibility of the method (RSD, relative standard deviation) was found to oscillate between 7 and 18% (generally close or lower than 10%).
Francisco J. Conde - One of the best experts on this subject based on the ideXlab platform.
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Optimization of an analytical methodology for the determination of alkyl- and methoxy-phenolic compounds by HS-SPME in biomass smoke
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Francisco J. Conde, Ana M. Afonso, Venerando González, Juan H. AyalaAbstract:A sampling and analysis method for the determination of 21 phenolic compounds in smoke samples from biomass combustion has been developed. The smoke is used to make Smoked Foods, following an artisanal procedure used in some parts of the Canary Islands. The sampling system consists of a Bravo H air sampler, two impingers, each one containing an aqueous solution of sodium hydroxide 0.1 mol L^−1, followed by a silica gel trap. The variables optimized to reach the best sampling conditions were volume of absorbent solution and sampling flow. Under the optimum conditions, 100 mL of absorbent solution of NaOH 0.10 mol L^−1 and 2 L min^−1 for the sampling flow, sampling efficiencies are higher than 80%. Analysis of phenolic compounds was carried out by headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography–mass spectrometry (GC-MS). Five different fiber coatings were employed in this study. By means of a central composite design, extraction time, salt concentration, and pH of the solution were optimized: 65-μm carbowax–divinylbenzene, extraction time 90 min, concentration in NaCl of 35% (m/v), and pH 2 yielded the highest response. Detection limits of phenol and their alkyl derivatives, guaiacol and eugenol, are between 1.13 and 4.60 ng mL^−1. 3-Methoxyphenol, 2,6-dimethoxyphenol, and vanillin have detection limits considerably higher. Good linearity ( R ^2≥0.98) was observed for all calibration curves in the established ranges. The reproducibility of the method (RSD, relative standard deviation) was found to oscillate between 7 and 18% (generally close or lower than 10%).
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Optimization of an analytical methodology for the determination of alkyl- and methoxy-phenolic compounds by HS-SPME in biomass smoke
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Francisco J. Conde, Ana M. Afonso, Venerando González, Juan H. AyalaAbstract:A sampling and analysis method for the determination of 21 phenolic compounds in smoke samples from biomass combustion has been developed. The smoke is used to make Smoked Foods, following an artisanal procedure used in some parts of the Canary Islands. The sampling system consists of a Bravo H air sampler, two impingers, each one containing an aqueous solution of sodium hydroxide 0.1 mol L^−1, followed by a silica gel trap. The variables optimized to reach the best sampling conditions were volume of absorbent solution and sampling flow. Under the optimum conditions, 100 mL of absorbent solution of NaOH 0.10 mol L^−1 and 2 L min^−1 for the sampling flow, sampling efficiencies are higher than 80%. Analysis of phenolic compounds was carried out by headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography–mass spectrometry (GC-MS). Five different fiber coatings were employed in this study. By means of a central composite design, extraction time, salt concentration, and pH of the solution were optimized: 65-μm carbowax–divinylbenzene, extraction time 90 min, concentration in NaCl of 35% (m/v), and pH 2 yielded the highest response. Detection limits of phenol and their alkyl derivatives, guaiacol and eugenol, are between 1.13 and 4.60 ng mL^−1. 3-Methoxyphenol, 2,6-dimethoxyphenol, and vanillin have detection limits considerably higher. Good linearity ( R ^2≥0.98) was observed for all calibration curves in the established ranges. The reproducibility of the method (RSD, relative standard deviation) was found to oscillate between 7 and 18% (generally close or lower than 10%).
Hiroshi Akiyama - One of the best experts on this subject based on the ideXlab platform.
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Concentrations of Polycyclic Aromatic Hydrocarbons in Smoked Foods in Japan.
Journal of food protection, 2019Co-Authors: Tomoaki Tsutsumi, Rika Adachi, Rieko Matsuda, Takahiro Watanabe, Reiko Teshima, Hiroshi AkiyamaAbstract:We evaluated the performance of a GC-MS/MS method for quantifying 16 polycyclic aromatic hydrocarbons (PAHs), which the Scientific Committee on Food and the Joint FAO/WHO Expert Committee on Food A...
Tomás Herraiz - One of the best experts on this subject based on the ideXlab platform.
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Identification and occurrence of 1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid: The main β-carboline alkaloid in Smoked Foods
Food Research International, 2003Co-Authors: Ekaterini Papavergou, Tomás HerraizAbstract:Abstract Tetrahydro-β-carboline alkaloids are biologically active compounds that occur in Foodstuffs. 1,2,3,4-Tetrahydro-β-carboline-3-carboxylic acid, a tetrahydro-β-carboline derived from a Pictet–Spengler condensation reaction among l -tryptophan and formaldehyde, was identified by GC–MS as its N-methoxycarbonyl methyl ester derivative in Smoked fish, sausage and cheese. The occurrence of this β-carboline was determined by RP-HPLC-fluorescence in numerous commercially available samples of these products and the concentrations ranges were 0.03–12.2 μg/g, 0.07–6.06 μg/g and 0.01–14.8 μg/g in Smoked fish, Smoked cheeses and Smoked sausages and meats, respectively. These results showed that 1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid is the main β-carboline in such products. Smoked Foods contained a higher relative amount (2–7 fold) of this compound in their exterior part exposed to the smoke than in their interior counterpart suggesting a reaction involving formaldehyde from smoke and tryptophan. Smoked products appear to be one of the food stuffs with the highest amount of this particular tetrahydro-β-carboline.
Ana M. Afonso - One of the best experts on this subject based on the ideXlab platform.
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Optimization of an analytical methodology for the determination of alkyl- and methoxy-phenolic compounds by HS-SPME in biomass smoke
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Francisco J. Conde, Ana M. Afonso, Venerando González, Juan H. AyalaAbstract:A sampling and analysis method for the determination of 21 phenolic compounds in smoke samples from biomass combustion has been developed. The smoke is used to make Smoked Foods, following an artisanal procedure used in some parts of the Canary Islands. The sampling system consists of a Bravo H air sampler, two impingers, each one containing an aqueous solution of sodium hydroxide 0.1 mol L^−1, followed by a silica gel trap. The variables optimized to reach the best sampling conditions were volume of absorbent solution and sampling flow. Under the optimum conditions, 100 mL of absorbent solution of NaOH 0.10 mol L^−1 and 2 L min^−1 for the sampling flow, sampling efficiencies are higher than 80%. Analysis of phenolic compounds was carried out by headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography–mass spectrometry (GC-MS). Five different fiber coatings were employed in this study. By means of a central composite design, extraction time, salt concentration, and pH of the solution were optimized: 65-μm carbowax–divinylbenzene, extraction time 90 min, concentration in NaCl of 35% (m/v), and pH 2 yielded the highest response. Detection limits of phenol and their alkyl derivatives, guaiacol and eugenol, are between 1.13 and 4.60 ng mL^−1. 3-Methoxyphenol, 2,6-dimethoxyphenol, and vanillin have detection limits considerably higher. Good linearity ( R ^2≥0.98) was observed for all calibration curves in the established ranges. The reproducibility of the method (RSD, relative standard deviation) was found to oscillate between 7 and 18% (generally close or lower than 10%).
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Optimization of an analytical methodology for the determination of alkyl- and methoxy-phenolic compounds by HS-SPME in biomass smoke
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Francisco J. Conde, Ana M. Afonso, Venerando González, Juan H. AyalaAbstract:A sampling and analysis method for the determination of 21 phenolic compounds in smoke samples from biomass combustion has been developed. The smoke is used to make Smoked Foods, following an artisanal procedure used in some parts of the Canary Islands. The sampling system consists of a Bravo H air sampler, two impingers, each one containing an aqueous solution of sodium hydroxide 0.1 mol L^−1, followed by a silica gel trap. The variables optimized to reach the best sampling conditions were volume of absorbent solution and sampling flow. Under the optimum conditions, 100 mL of absorbent solution of NaOH 0.10 mol L^−1 and 2 L min^−1 for the sampling flow, sampling efficiencies are higher than 80%. Analysis of phenolic compounds was carried out by headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography–mass spectrometry (GC-MS). Five different fiber coatings were employed in this study. By means of a central composite design, extraction time, salt concentration, and pH of the solution were optimized: 65-μm carbowax–divinylbenzene, extraction time 90 min, concentration in NaCl of 35% (m/v), and pH 2 yielded the highest response. Detection limits of phenol and their alkyl derivatives, guaiacol and eugenol, are between 1.13 and 4.60 ng mL^−1. 3-Methoxyphenol, 2,6-dimethoxyphenol, and vanillin have detection limits considerably higher. Good linearity ( R ^2≥0.98) was observed for all calibration curves in the established ranges. The reproducibility of the method (RSD, relative standard deviation) was found to oscillate between 7 and 18% (generally close or lower than 10%).