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1.
J Chromatogr A ; 1592: 64-70, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30718058

RESUMO

A new method for the simultaneous determination of two sweeteners (Advantame and Neotame) in processed foods using liquid chromatography (LC) with tandem mass spectrometry(MS/MS) was developed herein. Chromatographic separations were performed using an ACQUITY UPLC CSH C18 column at 40 °C via a mobile phase comprising 10-mmol/L ammonium formate and methanol. Samples were prepared via rapid dialysis using 30% methanol solution in a thermostatic shaker set at 160 rpm and 50 °C for 1 h. The matrix in the test solution had no effect on the identification and quantification of the compound without a clean-up step using solid-phase extraction (SPE). This method satisfied all validation criteria with a limit of quantification (LOQ) of 0.01 µg/g for all samples. Using this method, the amounts of Advantame and Neotame in 24 processed foods were subsequently investigated, with the results indicating their detection beyond the lower LOQ. Moreover, a multiple reaction monitoring information-dependent acquisition-enhanced product ion (MRM-IDA-EPI) method was developed and described to further enhance product-identification ability.


Assuntos
Cromatografia Líquida , Dipeptídeos/análise , Análise de Alimentos/métodos , Espectrometria de Massas em Tandem , Análise de Alimentos/normas , Extração em Fase Sólida , Edulcorantes/análise
2.
Shokuhin Eiseigaku Zasshi ; 59(5): 213-219, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30429419

RESUMO

A LC-MS/MS-based screening method was developed for stevia sweetener in processed foods. After extraction of stevia sweetener from processed foods by dialysis, the dialysate was diluted with water, and stevia sweetener was measured by LC-MS/MS. Recovery from 5 kinds of processed foods spiked with 10 mg/kg of stevioside (SS), 10 mg/kg of rebaudioside A (RS), or 100 mg/kg of α-glu-cosyltransferase-treated stevia (Gts) product was excellent, and no interfering peak was observed. Thirty-six commercial processed foods indicated as containing "stevia" were analyzed using this established method. Among them, 33 contained SS, 33 contained RS, and 11 contained Gts. Five products contained both stevia extract and Gts.


Assuntos
Diterpenos de Caurano/análise , Análise de Alimentos/métodos , Glucosídeos/análise , Stevia/química , Edulcorantes/análise , Cromatografia Líquida , Espectrometria de Massas em Tandem
3.
Shokuhin Eiseigaku Zasshi ; 59(3): 99-105, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30033995

RESUMO

A quantitative determination method of erythritol, maltitol, lactitol and trehalose in foods by HPLC, and confirmation method by LC-MS/MS were developed. HPLC analysis was performed on a separation column packed with amino group-binding polymer with acetonitrile-water (80 : 20) as the mobile phase. The column was operated at room temperature, and the three sugar alcohols and trehalose were quantified. LC-MS/MS confirmation was performed on an amino group-bound column with acetonitrile-ammonium acetate solution as the mobile phase, with detection in the SRM mode. At low sample dilution ratios, the analysis may be affected by matrix derived from the sample, but this can be suppressed by 1,000-fold or greater dilution. Recoveries of the three sugar alcohols and trehalose spiked into food samples, such as tea, jelly, tablets (ramune candy), and chocolate, exceeded 90% (CV≦6.1%) in HPLC and 94% (CV≦4.8%) in LC-MS/MS.


Assuntos
Eritritol/análise , Análise de Alimentos/métodos , Maltose/análogos & derivados , Álcoois Açúcares/análise , Trealose/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Maltose/análise , Espectrometria de Massas em Tandem
4.
Shokuhin Eiseigaku Zasshi ; 59(1): 18-23, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-29743463

RESUMO

A simple and useful method for the determination of nitrite in meat and fish products was developed. The sample (2.5 g) was extracted and cleaned up by dialysis in tris hydroxymethyl aminomethane solution with shaking at 80℃ for 2.5 hr. Nitrite in the dialysate was quantified by colorimetric analysis. Furthermore, the dialysate was cleaned up with SPE under cooling, and nitrite in the resulting solution was determined using LC-UV with an anion exchange column for confirmation. The recoveries of nitrite from frankfurter and fish sausage, fortified at the levels of 0.002 g/kg and the maximum usage dose (0.070 g/kg for meat products, 0.050 g/kg for fish sausage) ranged from 82.6 to 104.8% in colorimetric analysis and from 88.3 to 97.6% in LC-UV confirmation analysis. The values determined in various meat and fish products by the developed method and by the Japanese official method were approximately equivalent.


Assuntos
Diálise/métodos , Produtos Pesqueiros/análise , Aditivos Alimentares/análise , Análise de Alimentos/métodos , Carne/análise , Nitritos/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , Cromatografia Líquida/métodos , Colorimetria/métodos , Espectrofotometria Ultravioleta/métodos
5.
Shokuhin Eiseigaku Zasshi ; 59(1): 30-35, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-29743465

RESUMO

A quantitative analysis by HPLC of α-glucosyltransferase-treated stevia in foods was considered. This analysis is the way which hydrolyzed α-glucosyltransferase-treated stevia in the stevioside (SS) and the rebaudioside A (RS) using a glucoamylase. Recovery (%) of α-glucosyltransferase-treated stevia, spiked at 200 mg/kg in various foods, were more than 80% and the relative standard deviations were less than 5.0% as SS and RS for the rate of collection. A qualitative analysis by LC-MS/MS was performed 36 products of commercial foods containing stevia. We quantified of 11 products in which α-glucosyltransferase-treated stevia was detected. Quantitative value was at most 180 mg/kg as SS, at most 70 mg/kg as RS.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Glucosiltransferases , Stevia , Edulcorantes/análise , Cromatografia Líquida/métodos , Diterpenos de Caurano , Glucana 1,4-alfa-Glucosidase , Glucosídeos , Hidrólise , Espectrometria de Massas em Tandem/métodos
6.
Shokuhin Eiseigaku Zasshi ; 59(2): 73-79, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-29695675

RESUMO

The recoveries of xanthene dyes in the analysis of acidic tar-dyes in high-protein foods were improved by loading them onto polyamide columns at pH 8.5, instead of using the conventional pH 3-4 solution. The experimental scale was reduced to approximately half that of the conventional method. Furthermore, instead of eliminating the organic solvent in the extract by evaporation, the extract was diluted with water prior to PA column cleanup in order to reduce the ratio of organic solvent so that acidic tar-dyes would be better retained on the column. The above two procedures shortened the operation time and allowed for a simpler protocol. With this method, the recoveries of erythrosine, phloxine, and rose bengal from salted cod roe were 82, 88, and 74%, respectively. The recovery percentages were greatly improved compared to those achieved by conventional column loading at pH 3.5 (26, 44, and 18%, respectively). The recoveries of azo-dyes (Amaranth, New Coccine, Allura Red AC, Tartrazine, Sunset Yellow FCF) were also improved from 41-66 to 79-99%.


Assuntos
Análise de Alimentos/métodos , Corantes de Alimentos/análise , Proteínas na Dieta , Concentração de Íons de Hidrogênio , Nylons , Tartrazina
7.
Shokuhin Eiseigaku Zasshi ; 59(6): 275-281, 2018.
Artigo em Japonês | MEDLINE | ID: mdl-30626785

RESUMO

The aluminium (Al) content of Japanese confectionery and foods containing flour was investigated. Some of these items were investigated in previous studies, which examined foods that made use of baking powder containing aluminium potassium sulfate (Alum). Al was detected in 41 of the 123 samples at levels ranging from 0.01 (limit of quantitation) to 0.40 mg/g. The detection rate of Al in almost all confectionery (except Japanese confectionery) was decreased as compared with previous studies. However, the detection rate of Al in Japanese confectionery and foods containing flour was high. For 4 of the 41 samples tested, consuming one serving once a week would result in an Al intake exceeding the PTWI for young children (body weight=16 kg).


Assuntos
Compostos de Alúmen , Alumínio/análise , Sulfato de Cálcio , Farinha/análise , Contaminação de Alimentos/análise , Bicarbonato de Sódio , Amido , Criança , Humanos
8.
Shokuhin Eiseigaku Zasshi ; 58(3): 124-131, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-28690302

RESUMO

Following the previous report, a rapid dialysis method was developed for the extraction and purification of four artificial sweeteners, namely, sodium saccharide (Sa), acesulfame potassium (AK), aspartame (APM), and dulcin (Du), which are present in various foods. The method was evaluated by the addition of 0.02 g/kg of these sweeteners to a cookie sample, in the same manner as in the previous report. Revisions from the previous method were: reduction of the total dialysis volume from 200 to 100 mL, change of tube length from 55 to 50 cm, change of dialysate from 0.01 mol/L hydrochloric aqueous solution containing 10% sodium chloride to 30% methanol solution, and change of dialysis conditions from ambient temperature with occasional shaking to 50℃ with shaking at 160 rpm. As a result of these revisions, the recovery reached 99.3-103.8% with one hour dialysis. The obtained recovery yields were comparable to the recovery yields in the previous method with four hour dialysis.


Assuntos
Aspartame/análise , Aspartame/isolamento & purificação , Diálise/métodos , Análise de Alimentos/métodos , Compostos de Fenilureia/análise , Compostos de Fenilureia/isolamento & purificação , Sacarina/análise , Sacarina/isolamento & purificação , Edulcorantes/análise , Edulcorantes/isolamento & purificação , Tiazinas/análise , Tiazinas/isolamento & purificação , Carbonato de Cálcio , Cromatografia Líquida de Alta Pressão , Citratos , Soluções para Diálise , Combinação de Medicamentos , Temperatura Alta , Ácido Clorídrico , Óxido de Magnésio , Metanol , Cloreto de Sódio , Fatores de Tempo , Água
9.
Shokuhin Eiseigaku Zasshi ; 58(3): 160-165, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-28690307

RESUMO

Extraction and clean-up methods were examined for the analysis of acidic tar dyes in various high-protein foods. 1% Aqueous ammonia followed by ethanol, 1% aqueous ammonia-ethanol (1 : 1) mixture, and 1% aqueous ammonia-tetrahydrofuran (1 : 1) mixture were used in sequence for boiled fish paste (kamaboko), pounded fish cake (hanpen), and sausage. The sausage extract was centrifuged at low temperature to solidify and remove the contained fat. Salted cod roe with red pepper was extracted twice with 1% aqueous ammonia-ethanol (1 : 1) mixture, followed by extraction with 1% aqueous ammonia-tetrahydrofuran (1 : 1) mixture. A divinylbenzene-N-vinylpyrrolidone copolymer column was used for the clean-up of xanthen dyes. In the case of clogging-prone samples, the same type of large-particle-size column was used. A polyamide column was used for clean-up of the other dyes. When each dye was added at 5 µg/g in the foods, recoveries from kamaboko, hanpen, and sausage ranged from 76 to 102%, and the average recovery from the two types of salted cold roe with red pepper ranged from 45 to 98%.


Assuntos
Produtos Pesqueiros/análise , Análise de Alimentos/métodos , Corantes de Alimentos/análise , Corantes de Alimentos/isolamento & purificação , Alcatrões/análise , Alcatrões/isolamento & purificação , Xantenos/análise , Xantenos/isolamento & purificação , Concentração de Íons de Hidrogênio , Polivinil , Extração em Fase Sólida/métodos
10.
Shokuhin Eiseigaku Zasshi ; 58(3): 166-171, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-28690308

RESUMO

Stainless steel kitchenware and tableware on sale in Japan were investigated. Surface elemental composition ratios of 172 samples were analyzed by the fluorescence X-ray method. High levels of manganese (9.59-20.03%)were detected in 17 samples. This finding was confirmed by ICP analysis. Next, we conducted migration tests. Samples conformed to the Italian Specific Migration Limits. Moreover, lead and antimony were not detected in these samples, in accordance with the Japanese Food Sanitation Law.


Assuntos
Utensílios de Alimentação e Culinária , Legislação sobre Alimentos/normas , Manganês/análise , Aço Inoxidável/química , Antimônio/análise , Cádmio/análise , Cromo/análise , Ferro/análise , Japão , Chumbo/análise , Níquel/análise , Espectrometria por Raios X
11.
Shokuhin Eiseigaku Zasshi ; 58(1): 26-31, 2017.
Artigo em Japonês | MEDLINE | ID: mdl-28260729

RESUMO

Two yellow dyes, together with tartrazine (Y4), were found in cucumbers pickled in soy sauce, for which the use of tartrazine is permitted, by TLC, LC-DAD, and LC-MS. The retention times on LC chromatograms and the maximum absorbance wavelengths measured by LC-DAD of the two dyes were different from those of tartrazine. Mass spectra of the dyes indicated that these dyes lacked one sulfonyl group of tartrazine. The presence of two less sulfonated dyes in tartrazine has been reported. Hence, the two less sulfonated dyes were synthesized. The two dyes found in cucumbers were compared with the synthesized dyes by LC-DAD and LC-MS. Since the retention times of the dyes in cucumbers on the LC chromatograms, as well as their LC-DAD spectra and mass spectra, were found to be identical with those of the synthesized dyes, we concluded these dyes are the less sulfonated subsidiary dyes of tartrazine.


Assuntos
Cucumis sativus/química , Análise de Alimentos/métodos , Corantes de Alimentos/análise , Corantes de Alimentos/química , Contaminação de Alimentos/análise , Conservação de Alimentos , Alimentos de Soja/análise , Tartrazina/análise , Tartrazina/química , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Cromatografia em Camada Delgada , Espectroscopia de Ressonância Magnética , Espectrometria de Massas
12.
J AOAC Int ; 100(4): 1102-1109, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28236387

RESUMO

A method for simutaneously detecting 8 oil-soluble and 10 water-soluble (3 basic and 7 acidic) illegal dyes in foods was developed. The sample was mixed with water, followed by methanol and tetrahydrofuran. Transesterification with sodium methoxide was applied to the mixture, which allowed the triglycerides in the sample to be converted to fatty acid methyl esters. This treatment resulted in a biphasic mixture. Oil-soluble dyes and fatty acid methyl esters were deposited in the upper organic phase, which was cleaned using a silica-gel solid-phase extraction (SPE) column to remove the fatty acid methyl esters from the solution. The water-soluble dyes were deposited in the aqueous phase, and an Oasis hydrophilic-lipophilic-balanced SPE column was used to remove polar matrix components from the solution. The resulting dyes were subsequently analyzed via LC-diode-array detection using a single method. The practical LODs of the samples were defined as the lowest spiked dye concentrations at which the similarity coefficient for the spectra of the LC test solution and the corresponding reference standard solution were greater than 0.99, thus affording LODs of 0.5-1.0 µg/g. Recoveries of the dyes at a spiking level of 5.0 µg/g from soft drink, chili sauce, and mustard were generally greater than 70%. Recoveries from paprika powder were between 33 and 103%.


Assuntos
Análise de Alimentos , Corantes de Alimentos/análise , Contaminação de Alimentos/análise , Cromatografia Líquida , Extração em Fase Sólida
13.
Shokuhin Eiseigaku Zasshi ; 57(6): 207-212, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-28025455

RESUMO

The effect of pH of the clean-up process in the analysis of 11 permitted tar dyes in high protein food was investigated by using a handmade polyamide column (PA column) and Oasis HLB. Boiled fish paste spiked with the 11 dyes was extracted with appropriate solvents and the pH of the extract was adjusted to 3.0-7.0 in increments of 0.5, followed by clean-up with the PA column. At pH 3.0-5.5, precipitate formed in the extract clogged the column, and the recoveries of R3, R104 and R105 were 26-68%. At pH 6.0-7.0, clogging was not observed and the recoveries of the 3 dyes were somewhat higher, at 38-79%. The recoveries of other dyes were more than 80% at pH 3.0-7.0. With Oasis HLB, column loading was conducted at pH 11.0, and the recoveries of the 3 dyes improved to 70-83%. In conclusion, all 11 dyes could be cleaned-up with the PA column and Oasis HLB and the recoveries exceeded 70%.


Assuntos
Produtos Pesqueiros/análise , Análise de Alimentos/métodos , Corantes de Alimentos/análise , Corantes de Alimentos/isolamento & purificação , Produtos da Carne/análise , Alcatrões/análise , Alcatrões/isolamento & purificação , Concentração de Íons de Hidrogênio , Nylons , Extração em Fase Sólida/métodos , Soluções
14.
Shokuhin Eiseigaku Zasshi ; 57(5): 155-159, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-27784866

RESUMO

A rapid dialysis method for the analysis of stevioside (SS) and rebaudioside A (RS) in foods was developed. Minced samples (10 g) were packed into 30 cm net length dialysis tubing with 30% methanol to increase the dialysis efficiency. The dialysis tubing was put in a 100 mL centrifuge tube, and the total fluid volume was made up to 100 mL with 30% methanol. Dialysis was done with shaking while heating at 50℃. The dialysis times were reduced from 48-72 hr in the conventional method to 2 hr under these conditions. The dialysate was loaded on a C18 solid- phase extraction cartridge, and the cartridge was washed with 40% methanol. SS and RS were eluted from the cartridge with 80% methanol, and separated by reversed-phase HPLC. Recovery yields (%)of SS and RS, spiked at 0.02 g/kg in various foods, were 83.0-105.1% and the relative standard deviations were mostly less than 5%.


Assuntos
Diálise/métodos , Diterpenos de Caurano/análise , Aditivos Alimentares/análise , Análise de Alimentos/métodos , Glucosídeos/análise , Cromatografia Líquida de Alta Pressão/métodos , Diterpenos de Caurano/isolamento & purificação , Aditivos Alimentares/isolamento & purificação , Glucosídeos/isolamento & purificação , Extração em Fase Sólida , Temperatura , Fatores de Tempo
15.
Shokuhin Eiseigaku Zasshi ; 57(4): 96-100, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-27558227

RESUMO

A method for nicotinic acid (NA) and nicotinamide (NAA) analysis in meats was developed. NA and NAA were extracted from meats or meat products with metaphosphate aqueous solution. The extract was cleaned up with an Oasis MCX cartridge. The cartridge was washed with 2% acetic acid (v/v) and acetic acid-methanol solution. NA and NAA were eluted with ammonia-methanol solution. NA and NAA in the eluate were chromatographed on a Scherzo SM-C18 (3.0×150 mm, 3.0 µm) column with 20 mmol/L ammonium acetate containing 0.1% acetic acid-acetonitrile (97 : 3) as a mobile phase and were monitored at 261 nm. Quantification was performed by LC and LC-MS/MS. Calibration curves showed high linearity (correlation coefficient>0.998) between 1-25 µg/mL for LC and LC-MS/MS. Recoveries were 84-108% (CV≦5.8%) by HPLC and 79-105% (CV≦9.0%) by LC-MS/MS. The limit of quantitation for NA was 0.005-0.01 g/kg and that for NAA was 0.01-0.02 g/kg.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Aditivos Alimentares/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Produtos da Carne/análise , Carne/análise , Niacinamida/análise , Ácidos Nicotínicos/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos
16.
Shokuhin Eiseigaku Zasshi ; 57(3): 67-71, 2016.
Artigo em Japonês | MEDLINE | ID: mdl-27440751

RESUMO

A simple and efficient method for the determination of propionic acid (PA) in foods was developed. The sample was cleaned up by dialysis, and PA in the resulting solution was extracted into ethyl acetate for GC analysis. Sodium sulfate was used as a salting-out agent in the extraction process, and GC-FID and GC-MS were successfully applied to the determination and confirmation of PA, respectively. The recoveries were in the range of 98.9-104.4% at the addition level of 0.2 g/kg from 6 foods, bread, cake, cheese, worcester sauce, vinegar-pickles and yogurt. To evaluate the performance of the developed method, recoveries from bread, cake and cheese were compared with those of the notified method at the maximal allowable addition level of PA as a preservative for each food. Recoveries of 98.2-99.5% for the developed method and 91.2-92.0% for the notified method were obtained. The analytical limit was 0.1 g/kg in samples for both determination and confirmation.


Assuntos
Cromatografia Gasosa/métodos , Diálise , Análise de Alimentos/métodos , Conservantes de Alimentos/análise , Extração Líquido-Líquido/métodos , Propionatos/análise , Acetatos , Conservantes de Alimentos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Propionatos/isolamento & purificação , Soluções , Sulfatos
17.
Food Addit Contam Part B Surveill ; 9(3): 185-90, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27092423

RESUMO

Aluminium (Al) levels of 90 food samples were investigated. Nineteen samples contained Al levels exceeding the tolerable weekly intake (TWI) for young children [body weight (bw): 16 kg] when consuming two servings/week. These samples were purchased multiple times at specific intervals and were evaluated for Al levels. Al was detected in 27 of the 90 samples at levels ranging from 0.01 (limit of quantitation) to 1.06 mg/g. Of these, the Al intake levels in two samples (cookie and scone mix, 1.3 and 2 mg/kg bw/week, respectively) exceeded the TWI as established by European Food Safety Authority, although the level in the scone mix was equivalent to the provisional TWI (PTWI) as established by Joint Food and Agriculture Organization of the United Nations/World Health Organization Expert Committee on Food Additives. The Al levels markedly decreased in 14 of the 19 samples with initially high Al levels. These results indicated reductions in the Al levels to below the PTWI limits in all but two previously identified food samples.


Assuntos
Compostos de Alumínio/química , Alumínio/análise , Aditivos Alimentares/química , Análise de Alimentos , Contaminação de Alimentos , Alumínio/toxicidade , Pão/efeitos adversos , Pão/análise , Pão/economia , Pão/normas , Pré-Escolar , Culinária , Dieta/efeitos adversos , Dieta/etnologia , Aditivos Alimentares/efeitos adversos , Aditivos Alimentares/normas , Análise de Alimentos/economia , Inspeção de Alimentos/métodos , Humanos , Hidrólise/efeitos da radiação , Indicadores e Reagentes/química , Internacionalidade , Limite de Detecção , Micro-Ondas , Ácido Nítrico/química , Nível de Efeito Adverso não Observado , Reprodutibilidade dos Testes , Lanches , Espectrofotometria Atômica , Tóquio
18.
Artigo em Inglês | MEDLINE | ID: mdl-26730677

RESUMO

A method was developed to determine the aromatic hydrocarbon to total hydrocarbon ratio of mineral oil in commercial lubricants; a survey was also conducted of commercial lubricants. Hydrocarbons in lubricants were separated from the matrix components of lubricants using a silica gel solid phase extraction (SPE) column. Normal-phase liquid chromatography (NPLC) coupled with an evaporative light-scattering detector (ELSD) was used to determine the aromatic hydrocarbon to total hydrocarbon ratio. Size exclusion chromatography (SEC) coupled with a diode array detector (DAD) and a refractive index detector (RID) was used to estimate carbon numbers and the presence of aromatic hydrocarbons, which supplemented the results obtained by NPLC/ELSD. Aromatic hydrocarbons were not detected in 12 lubricants specified for use for incidental food contact, but were detected in 13 out of 22 lubricants non-specified for incidental food contact at a ratio up to 18%. They were also detected in 10 out of 12 lubricants collected at food factories at a ratio up to 13%. The centre carbon numbers of hydrocarbons in commercial lubricants were estimated to be between C16 and C50.


Assuntos
Hidrocarbonetos Aromáticos/análise , Lubrificantes/química , Óleo Mineral/química , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida
19.
Shokuhin Eiseigaku Zasshi ; 55(1): 13-8, 2014.
Artigo em Japonês | MEDLINE | ID: mdl-24598222

RESUMO

A simple and rapid dialysis method was developed for the extraction and purification of four artificial sweeteners, namely, sodium saccharin (Sa), acesulfame potassium (AK), aspartame (APM), and dulcin (Du), which are present in various foods. Conventional dialysis uses a membrane dialysis tube approximately 15 cm in length and is carried out over many hours owing to the small membrane area and owing to inefficient mixing. In particular, processed cereal products such as cookies required treatment for 48 hours to obtain satisfactory recovery of the compounds. By increasing the tube length to 55 cm and introducing efficient mixing by inversion at half-hour intervals, the dialysis times of the four artificial sweeteners, spiked at 0.1 g/kg in the cookie, were shortened to 4 hours. Recovery yields of 88.9-103.2% were obtained by using the improved method, whereas recovery yields were low (65.5-82.0%) by the conventional method. Recovery yields (%) of Sa, AK, APM, and Du, spiked at 0.1 g/kg in various foods, were 91.6-100.1, 93.9-100.1, 86.7-100.0 and 88.7-104.7 using the improved method.


Assuntos
Aspartame/isolamento & purificação , Diálise/métodos , Análise de Alimentos/métodos , Compostos de Fenilureia/isolamento & purificação , Sacarina/isolamento & purificação , Edulcorantes/isolamento & purificação , Tiazinas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Fatores de Tempo
20.
Shokuhin Eiseigaku Zasshi ; 54(5): 358-63, 2013.
Artigo em Japonês | MEDLINE | ID: mdl-24190289

RESUMO

A reliable quantitative determination method of sugar alcohols, D-mannitol, xylitol and D-sorbitol, in food samples by HPLC, and a simple confirmation method by LC-MS were developed. Quantitative HPLC analysis was performed using a separation column packed with polystyrene cation exchange resin of sulfonic acid type, and with pure distilled water as the mobile phase. This column, operated at 0.85 mL/min flow rate of mobile phase and 50℃ column oven temperature, completely separated the three sugar alcohols. Further, these three sugar alcohols were well separated from erythritol and other sugars (sucrose, D-glucose, D-xylose and D-fructose). Recoveries of the three sugar alcohols spiked into food samples, such as orange juice, yogurt, chewing gum and milk, exceeded 91% and the values of coefficient of variance were below 3.1%. A triple extraction process with 80% ethanol was needed for biscuit to achieve recoveries exceeding 82%. LC-MS was carried out on a NH2 column with acetonitrile-water (9 : 1) as the mobile phase, and this afforded partial but acceptable separation of the three sugar alcohols with in 10 minutes. Ion peaks derived from [M-H](-) and [M+Cl](-) were clearly detected for all three sugar alcohols in the negative electrospray inization mode at 30 V cone voltage. The positive electrospray ionization mode produced the ions [M+Na](+) and [M+Na+CH3CN](+). These characteristic ions served to confirm the presence of the sugar alcohols in food samples.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Análise de Alimentos/métodos , Espectrometria de Massas/métodos , Álcoois Açúcares/análise
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