Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22.132
Filtrar
1.
J Chromatogr A ; 1645: 462075, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-33848661

RESUMEN

An electrophoretic method (on-line coupled capillary isotachophoresis and capillary zone electrophoresis) with conductometric detection for the determination of free taurine in selected food and feed is described. Taurine is converted to isethionic acid by van Slyke method. Under optimized conditions (leading electrolyte: 5 mM HCl, 10 mM glycylglycine, and 0.05% 2-hydroxyethyl cellulose solution, pH 3.2; terminating electrolyte: 10 mM citric acid; background electrolyte: 50 mM acetic acid, 20 mM glycylglycine, and 0.1% 2-hydroxyethyl cellulose solution, pH 3.7), isethionic acid is separated from other sample components in anionic mode and detected using a conductimeter within 15 minutes. The performance method characteristics, such as linearity (25 - 1250 ng/mL), accuracy (99 ± 9%), repeatability (3.9%), reproducibility (4.3%), limits of detection (3 ng/mL) and quantification (10 ng/mL) were evaluated. By analysing 20 food and pet food samples the method was proved suitable for routine analysis. High sensitivity and selectivity, short analysis time and low costs are significant features of the presented method.


Asunto(s)
Electroforesis Capilar/métodos , Isotacoforesis/métodos , Taurina/análisis , Alimentación Animal/análisis , Análisis de los Alimentos/métodos , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados
2.
Food Chem ; 355: 129525, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-33799266

RESUMEN

Available nuclear gene sequences for meat detection are still rare and little applicability in the investigation of new types of meat adulteration such as fox, mink and raccoon dog was performed. In the present work, we developed a reliable qualitative and quantitative detection method for fur-bearing animal meat based on droplet digital PCR (ddPCR). Three sets of primers and probes targeted nuclear genes for fox, mink and raccoon dog were designed for ddPCR system; In addition, turkey was selected as internal reference to transform the copy numbers to the fraction of target species. Results indicated that the dynamic ranges of three fur-bearing animals were all from 1% to 90%; the limit of detection (LOD) and limit of quantification (LOQ) for three fur-bearing animals were same, with LOD 0.1% (w/w) and LOQ 1% (w/w). Moreover, we confirmed that different additives had no effect on quantification accuracy in the ddPCR assay.


Asunto(s)
Pelaje de Animal , Análisis de los Alimentos/métodos , Manipulación de Alimentos , Carne/análisis , Reacción en Cadena de la Polimerasa/métodos , Animales , Cartilla de ADN/genética , Límite de Detección , Mamíferos
3.
Molecules ; 26(6)2021 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-33805641

RESUMEN

An innovative process for the adsorption of the hydrophobic Basil-Oil (BO) into the hydrophilic food byproduct chitosan (CS) and the development of an advanced low-density polyethylene/chitosan/basil-oil (LDPE/CS_BO) active packaging film was investigated in this work. The idea of this study was the use of the BO as both a bioactive agent and a compatibilizer. The CS was modified to a CS_BO hydrophobic blend via a green evaporation/adsorption process. This blend was incorporated directly in the LDPE to produce films with advanced properties. All the obtained composite films exhibited improved packaging properties. The film with 10% CS_BO content exhibited the best packaging properties, i.e., 33.0% higher tensile stress, 31.0% higher water barrier, 54.3% higher oxygen barrier, and 12.3% higher antioxidant activity values compared to the corresponding values of the LDPE films. The lipid oxidation values of chicken breast fillets which were packaged under vacuum using this film were measured after seven and after fourteen days of storage. These values were found to be lower by around 41% and 45%, respectively, compared with the corresponding lipid oxidation values of pure LDPE film.


Asunto(s)
Pollos , Quitosano , Embalaje de Alimentos/métodos , Aceites Vegetales , Polietileno , Animales , Antioxidantes/química , Plásticos Biodegradables/química , Rastreo Diferencial de Calorimetría , Quitosano/química , Análisis de los Alimentos , Conservación de Alimentos/métodos , Tecnología de Alimentos , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Peroxidación de Lípido , Microscopía Electrónica de Rastreo , Permeabilidad , Aceites Vegetales/química , Polietileno/química , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción , Termogravimetría , Factores de Tiempo , Difracción de Rayos X
4.
Food Chem ; 355: 129640, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-33799253

RESUMEN

The aim of this study was to develop methods for the determination of short- and medium-chain chlorinated paraffins (SCCPs; MCCPs) in vegetable oils and fish employing gas chromatography coupled with high-resolution mass spectrometry because of a lack of information on the presence of chlorinated paraffins in food consumed in Europe. For isolation of CPs from fish, an ethyl acetate extraction followed by a clean-up of the extract by gel permeation chromatography was performed. The same purification step was used for the isolation of CPs from the vegetable oils. The concentration range for SCCPs was <10-389 ng/g lipid weight (lw, mean 36 ng/g lw for the oils and 28 ng/g lw for the fish) and that for MCCPs was <20-543 ng/g lw (mean 55 ng/g lw for the oils and 59 ng/g lw for the fish). There was found a high variability in concentrations of CPs influenced by area of origin.


Asunto(s)
Peces , Análisis de los Alimentos/métodos , Cromatografía de Gases y Espectrometría de Masas , Halogenación , Parafina/análisis , Parafina/química , Aceites Vegetales/química , Animales , Monitoreo del Ambiente , Contaminación de Alimentos/análisis
5.
Food Chem ; 355: 129662, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-33799255

RESUMEN

A facile in-tube solid phase microextraction (in-tube SPME) procedure was developed to enrich ractopamine before HPLC-UV analysis. This was achieved by employing amide groups modified polysaccharide-silica hybrid monolith as an efficient sorbent. The monolith was synthesized by a simple reaction with agarose oxide and tetramethoxylisane, followed by the modification of amide groups via subsequent ring opening, "thiol-ene" click and dehydration reactions. Under the optimized extraction conditions, the enrichment factors for ractopamine, dopamine, clenbuterol, para-methylphenol and phenol were determined to be 50.5, 32.2, 4.8, 2.1 and 1.8, respectively. The monolithic column has ideal selectivity for ractopamine. Coupled with HPLC-UV, this method demonstrated a linearity within 2.0-800 ng/g for ractopamine with spiking in pork muscles (R2 = 0.9958). The LOD was 0.64 ng/g (S/N = 3) and recoveries ranged from 85.2 to 108.1% (n = 3). This approach provides a feasible way for analysis of trace ractopamine in biological samples.


Asunto(s)
Cromatografía Líquida de Alta Presión , Análisis de los Alimentos/métodos , Músculos/química , Fenetilaminas/análisis , Carne de Cerdo/análisis , Dióxido de Silicio/química , Microextracción en Fase Sólida , Amidas/química , Animales , Fenetilaminas/aislamiento & purificación , Porcinos
6.
Molecules ; 26(5)2021 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-33800407

RESUMEN

An effect-directed profiling method was developed to investigate 17 different fortified plant extracts for potential benefits. Six planar effect-directed assays were piezoelectrically sprayed on the samples separated side-by-side by high-performance thin-layer chromatography. Multipotent compounds with antibacterial, α-glucosidase, ß-glucosidase, AChE, tyrosinase and/or ß-glucuronidase-inhibiting effects were detected in most fortified plant extracts. A comparatively high level of antimicrobial activity was observed for Eleutherococcus, hops, grape pomace, passiflora, rosemary and Eschscholzia. Except in red vine, black radish and horse tail, strong enzyme inhibiting compounds were also detected. Most plants with anti-α-glucosidase activity also inhibited ß-glucosidase. Green tea, lemon balm and rosemary were identified as multipotent plants. Their multipotent compound zones were characterized by high-resolution mass spectrometry to be catechins, rosmarinic acid, chlorogenic acid and gallic acid. The results pointed to antibacterial and enzymatic effects that were not yet known for plants such as Eleutherococcus and for compounds such as cynaratriol and caffeine. The nontarget effect-directed profiling with multi-imaging is of high benefit for routine inspections, as it provides comprehensive information on the quality and safety of the plant extracts with respect to the global production chain. In this study, it not only confirmed what was expected, but also identified multipotent plants and compounds, and revealed new bioactivity effects.


Asunto(s)
Análisis de los Alimentos/métodos , Extractos Vegetales/química , Antibacterianos/farmacología , Bioensayo/métodos , Cromatografía Líquida de Alta Presión/métodos , Cromatografía en Capa Delgada/métodos , Inhibidores Enzimáticos , Alimentos , Espectrometría de Masas/métodos
7.
Food Chem ; 355: 129656, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-33813158

RESUMEN

A visible-light-responsive azobenzene derivative, 3,5-dichloro-4-((2,6-dichloro-4-(methacryloyloxy)phenyl)diazenyl)benzoic acid, was synthesized and used as the functional monomer to fabricate a visible-light-responsive core-shell structured surface molecularly imprinted polymer (PS-co-PMAA@VSMIP). After removal of the sacrificial PS-co-PMAA core, a hollow structured surface molecularly imprinted polymer (HVSMIP) was obtained. Both the PS-co-PMAA@VSMIP and HVSMIP were used for the detection of chlorpyrifos, a moderately toxic organophosphate pesticide. They exhibited good visible-light-responsive properties (550 nm for trans→cis and 440 nm for cis→trans isomerization for an azobenzene chromophore) in ethanol/water (9:1, v/v). Compared with the PS-co-PMAA@VSMIP, the HVSMIP had a larger surface area, pore volume, binding capacity, imprinting effect, maximum chemical binding capacity, dissociation constant, and photo-isomerization rate. The HVSMIP was applied to detect trace chlorpyrifos in fruit and vegetable samples. This was achieved by measuring the trans→cis rate constant of the HVSMIP in the sample solution, with good recoveries, low relative standard deviations, and a low detection limit.


Asunto(s)
Cloropirifos/análisis , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Frutas/química , Luz , Verduras/química , /síntesis química , Agua/química
8.
Int J Mol Sci ; 22(6)2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33806998

RESUMEN

In recent times, food safety has become a topic of debate as the foodborne diseases triggered by chemical and biological contaminants affect human health and the food industry's profits. Though conventional analytical instrumentation-based food sensors are available, the consumers did not appreciate them because of the drawbacks of complexity, greater number of analysis steps, expensive enzymes, and lack of portability. Hence, designing easy-to-use tests for the rapid analysis of food contaminants has become essential in the food industry. Under this context, electrochemical biosensors have received attention among researchers as they bear the advantages of operational simplicity, portability, stability, easy miniaturization, and low cost. Two-dimensional (2D) nanomaterials have a larger surface area to volume compared to other dimensional nanomaterials. Hence, researchers nowadays are inclined to develop 2D nanomaterials-based electrochemical biosensors to significantly improve the sensor's sensitivity, selectivity, and reproducibility while measuring the food toxicants. In the present review, we compile the contribution of 2D nanomaterials in electrochemical biosensors to test the food toxicants and discuss the future directions in the field. Further, we describe the types of food toxicity, methodologies quantifying food analytes, how the electrochemical food sensor works, and the general biomedical properties of 2D nanomaterials.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Análisis de los Alimentos/métodos , Inocuidad de los Alimentos , Nanoestructuras , Contaminación de Alimentos/análisis , Sustancias Peligrosas/análisis , Humanos , Nanoestructuras/química , Reproducibilidad de los Resultados
9.
Int J Mol Sci ; 22(6)2021 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-33809986

RESUMEN

The approaches based on high-resolution analytical techniques, such as nuclear magnetic resonance or mass spectrometry coupled to chromatographic techniques, have a determining role in several of the stages necessary for the development of functional foods. The analyses of botanical extracts rich in bioactive compounds is one of the fundamental steps in order to identify and quantify their phytochemical composition. However, the compounds characterized in the extracts are not always responsible for the bioactive properties because they generally undergo metabolic reactions before reaching the therapeutic targets. For this reason, analytical techniques are also applied to analyze biological samples to know the bioavailability, pharmacokinetics and/or metabolism of the compounds ingested by animal or human models in nutritional intervention studies. In addition, these studies have also been applied to determine changes of endogenous metabolites caused by prolonged intake of compounds with bioactive potential. This review aims to describe the main types and modes of application of high-resolution analytical techniques in all these steps for functional food development.


Asunto(s)
Análisis de los Alimentos/métodos , Alimentos Funcionales/análisis , Animales , Productos Biológicos/análisis , Cromatografía Liquida , Cromatografía de Gases y Espectrometría de Masas , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Nutrientes/análisis , Fitoquímicos/análisis
10.
J Agric Food Chem ; 69(16): 4578-4603, 2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33851531

RESUMEN

Acrylamide, a food processing contaminant with demonstrated genotoxicity, carcinogenicity, and reproductive toxicity, is largely present in numerous prominent and commonly consumed food products that are produced by thermal processing methods. Food regulatory bodies such as the U.S. Food and Drug Administration (U.S. FDA) and European Union Commission regulations have disseminated various acrylamide mitigation strategies in food processing practices. Hence, in the wake of such food and public health safety efforts, there is a rising demand for economic, rapid, and portable detection and quantification methods for these contaminants. Since conventional quantification techniques like liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS) methods are expensive and have many drawbacks, sensing platforms with various transduction systems have become an efficient alternative tool for quantifying various target molecules in a wide variety of food samples. Therefore, this present review discusses in detail the state of robust, nanomaterials-based and other bio/chemical sensor fabrication techniques, the sensing mechanism, and the selective qualitative and quantitative measurement of acrylamide in various food materials. The discussed sensors use analytical measurements ranging from diverse and disparate optical, electrochemical, as well as piezoelectric methods. Further, discussions about challenges and also the potential development of the lab-on-chip applications for acrylamide detection and quantification are entailed at the end of this review.


Asunto(s)
Acrilamida , Nanoestructuras , Acrilamida/análisis , Cromatografía Liquida , Análisis de los Alimentos , Contaminación de Alimentos/análisis
11.
Food Chem ; 355: 129555, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-33831729

RESUMEN

Phenolic compounds are the important taste source of tea infusion. In this paper, the phenolic compounds in tea extracts were separated by high-performance thin-layer chromatography (HPTLC), and then in-situ determined by desorption electrospray ionization mass spectrometry (DESI-MS). Total 44 phenolic compounds in tea extracts were accurately confirmed by NIST library as well as reference substances. The clustering results of heat-map can better reflect the differences of phenolic compounds in different categories and subcategories of teas. Besides, the contents of hydrolyzable tannins, including galloylglucose, digalloylglucose, trigalloyglucose and strictinin, were positively correlated with the grades of green tea. The method validation and quantification results of exemplified five phenolic compounds in teas were also obtained, and LODs, LOQs and recoveries were ranging between 1.5-15.9 µg/mL, 5.1-53.1 µg/mL, and 79%-117.6%, respectively. Moreover, HPTLC-DESI-MS can save tenfold analytical time compared to HPLC-MS. Therefore, HPTLC-DESI-MS was a rapid, efficient characterization method of phenolic compounds in tea extracts.


Asunto(s)
Cromatografía en Capa Delgada , Análisis de los Alimentos/métodos , Fenol/análisis , Espectrometría de Masa por Ionización de Electrospray , Gusto , Té/química , Factores de Tiempo
12.
Food Chem ; 354: 129568, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-33799063

RESUMEN

The identification of geographical origin is an important factor in evaluating the authenticity of honey. However, at present, there are few studies concerning the honey of Apis cerana Fabricius (A. cerana, Asiatic honeybee). To identify geographical origin, we used two common methods (multi-physicochemical parameters and phenolic chromatographic fingerprints) but achieved only poor identification. To compensate for this shortcoming, we established an ICP-MS-based ionomics method using 18 elements in 27 A. cerana honey samples from three different areas in Shaanxi Province, China. Multivariate analysis showed that significant differences in contents can be used to discriminate the geographical origin of A. cerana honey. The method was further validated using an independent test set of 11 samples with 90.91% accuracy, demonstrating its potential for the identification and prediction of the geographical origin of honey.


Asunto(s)
Abejas , Análisis de los Alimentos/métodos , Geografía , Miel/análisis , Espectrometría de Masas , Animales , Análisis Espectral
13.
J Chromatogr A ; 1645: 462129, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-33864987

RESUMEN

Comprehensive two-dimensional liquid chromatography is a well-established method for the unraveling of very complex real-world samples. With regard to food and natural products such a technique turned out to be a very promising approach due to its high resolving power and improved identification capability, especially in combination with mass spectrometry. In this context, polyphenols comprise a particular complex class of bioactive compounds, due to their nature and content in commonly consumed foodstuffs, making their analysis challenging. The present contribution shows an overview of the two commonly employed approaches used for polyphenol analysis, viz. RP-LC × RP-LC and HILIC × RP-LC. Furthermore, the latest implementations as well as limitations and future perspectives are critically reported.


Asunto(s)
Productos Biológicos/química , Cromatografía Liquida/métodos , Análisis de los Alimentos/métodos , Polifenoles/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Espectrometría de Masas
14.
Food Chem ; 352: 129312, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33652193

RESUMEN

High-value acacia honey is often adulterated with inexpensive high fructose corn syrup (HFCS), due to their similar color and sugar composition. α­Dicarbonyl compounds formed by Maillard reaction or caramelization during heat treatment or storage, differ between HFCS and honey due to differences in starting materials and processing methods. In this study, we compared α-dicarbonyl compounds in acacia honey and HFCS by Ion Mobility-Mass Spectrometry and multivariate statistical analysis. Through α-dicarbonyl compound derivatization with o-phenylenediamine, we screened a marker with 189.1023 m/z and 139.3 Å2 Collision Cross-Section that can distinguish HFCS from acacia honey. Nuclear magnetic resonance spectra identified this marker compound as 3,4-dideoxypentosulose. We then used chromatography-coupled tandem mass spectrometry to quantitate 3,4-dideoxypentosulose in market samples of honey and HFCS and found that 3,4-dideoxypentosulose was negligible (<0.098 mg/kg) in honey, but prevalent in HFCS (≧1.174 mg/kg), indicating 3,4-dideoxypentosulose can serve as an alternative indicator of HFCS adulteration of acacia honey.


Asunto(s)
Acacia/química , Bebidas/análisis , Cromatografía Líquida de Alta Presión , Análisis de los Alimentos/métodos , Jarabe de Maíz Alto en Fructosa/análisis , Espectrometría de Movilidad Iónica , Espectrometría de Masas en Tándem , Calidad de los Alimentos , Fraude/prevención & control
15.
Food Chem ; 352: 129343, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33652194

RESUMEN

In this work, the interaction of wine macromolecules with a bovine serum albumin (BSA) was investigated using fluorescence correlation spectroscopy (FCS). FCS offers the opportunity to study molecular and macromolecular aggregation without disturbing the wine by introducing only very small amounts of fluorescently labelled molecules to the system. It was observed that the diffusion coefficient of fluorescently labelled BSA varies with the addition of wine macromolecules, indicating changes in the protein conformation and the formation of complexes and aggregates. The addition of a wine polysaccharide rhamnogalacturonan II-enriched fraction led to aggregation, while addition of a mannoprotein-enriched fraction exhibited a protective effect on protein aggregation. Proteins strongly interacted with tannins, leading to the precipitation of protein-tannin complexes, while the presence of polysaccharides prevented this precipitation. Finally, the application of FCS was demonstrated in real wines, to investigate the problem of protein haze formation through live monitoring of heat-induced aggregation in wine.


Asunto(s)
Análisis de los Alimentos , Sustancias Macromoleculares/química , Espectrometría de Fluorescencia , Vino/análisis
16.
Food Chem ; 352: 129331, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33652198

RESUMEN

A novel density-tunable liquid-phase microextraction (DT-LPME) system was developed with high-density deep eutectic solvents (DESs) as extractant and low-density organic solvents as emulsifier and density regulator. DES-rich phase was induced to form in the bottom or in the top by adjusting the emulsifier amount. This system was used to directly extract polycyclic aromatic hydrocarbons (PAHs) from liquid and solid foods, and the obtained DES-rich phase was easy to be collected for quantification. The method (LPME with HPLC-fluorescence detector) has linearity (R2 > 0.9974), detection limits of 0.6-4.2 ng L-1 for liquid foods and 0.05-0.35 ng g-1 for solid foods, recoveries of 86.2-114.9%, and intra-day/inter-day RSDs below 6.6%. The method was applied to detect PAHs in real samples, and the PAHs residue was found in honey and five solid foods. The DT-LPME method is simple, fast, green and suitable for direct extraction of analytes from both liquid and solid samples.


Asunto(s)
Microextracción en Fase Líquida/métodos , Plantas Medicinales/química , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Solventes/química , Té/química , Análisis de los Alimentos , Miel/análisis , Límite de Detección
17.
Food Chem ; 352: 129341, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33657483

RESUMEN

A healthy life means a balance between physical activity and a diet rich in fruits and vegetables, however, some plant-based foods can have certain adverse effects due to the presence of anti-nutritional factors, such as lectins, capable of binding molecules and preventing their normal assimilation. The level of lectins in Synsepalum dulcificum fruit was determined by hemagglutination assays in human blood, and its comparison with foods characterized as having high and low lectin content. The relative hemagglutinating activity of berries from Synsepalum dulcificum compared to our positive high lectin content food reference (Pinto bean) corresponds to 3.13-6.25%, representing safe levels for nutritional food.


Asunto(s)
Análisis de los Alimentos/normas , Lectinas de Plantas/análisis , Synsepalum/química , Dieta , Frutas/química , Humanos , Estándares de Referencia
18.
Food Chem ; 352: 129330, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33657486

RESUMEN

Pregnancy test strips are one of the most mature and widely used commercial lateral flow devices used to determine pregnancy. Being a simple and rapid detection method, human chorionic gonadotropin (hCG) was used with different aptamers (hCG-apt) as probes for the detection of metal ions, small organic molecules, and proteins. Quantitative detection of target analytes was achieved using a smartphone app and a portable device developed in our laboratory. The results showed detection ranges of 1 nM-1 µM, 0.1 nM-10 µM and 32 nM-500 nM for Pb2+, chloramphenicol, and ß-lactoglobulin, respectively, and the corresponding visual detection limits in dairy products were 5 nM, 1 nM and 50 nM, respectively. Based on these results, rapid detection of multiple analytes can be realized through aptamer modification, thereby broadening the application range of commercial lateral flow devices for analysis of food chemistry.


Asunto(s)
Aptámeros de Nucleótidos/metabolismo , Productos Lácteos/análisis , Compuestos Férricos/química , Análisis de los Alimentos/instrumentación , Grafito/química , Pruebas de Embarazo/instrumentación , Teléfono Inteligente , Animales , Femenino , Oro/química , Humanos , Límite de Detección , Embarazo
19.
Food Chem ; 352: 129327, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33690077

RESUMEN

This paper describes a voltammetric method and data analysis program developed for the detection of arsenic(III) in commercial apple juice. Arsenic(III) was detected using square wave stripping voltammetry with gold nanoparticle modified screen printed electrodes. The only sample pretreatment performed was the addition of a 100 mM phosphate buffer with a pH of 7. To compensate for interference from high ascorbic acid concentrations, a data analysis program was developed in MATLAB to fit a non-linear baseline, allowing for accurate peak height measurement. With this data analysis program, the developed methodology had a sensitivity of 0.1007 µA (µg L-1)-1 and a limit of detection of 16.73 µg L-1. A comparison between the voltammetric method and graphite furnace atomic absorption spectroscopy showed no bias in the voltammetric results and a good correlation between the two sets of predicted concentrations, with an R2 of 0.939.


Asunto(s)
Arsénico/análisis , Carbono/química , Electroquímica/instrumentación , Jugos de Frutas y Vegetales/análisis , Oro/química , Malus/química , Nanopartículas del Metal/química , Electrodos , Análisis de los Alimentos/instrumentación , Impresión , Factores de Tiempo
20.
Food Chem ; 351: 129351, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-33647687

RESUMEN

Histamine is a biogenic amine that is formed from histidine by action of the enzyme histidine decarboxylase and can be toxic at high intakes. Thus, the quantification of these analytes in foods constitutes a significant axis of food safety. In this study we present the development, validation and application of a new method for the determination of histamine and its precursor histidine in fish products and oriental sauces. The analytes were separated rapidly through a cation exchange column using an acidic mobile phase (7 mmol L-1 nitric acid) and reacted downstream with o-phthalaldehyde in post-column mode in the absence of nucleophilic reagents. The derivatives were detected spectrofluorimetrically at λex/λem. = 360/440 nm. Following investigation of the chromatographic and post-column conditions, the method was validated as for its intended applications. The limits of detection were 0.16 and 0.17 µmol L-1 for histidine and histamine respectively (ca. 0.1 mg kg-1) and the precision was better than 5%. Various food samples were successfully analyzed without matrix interferences following minimal pretreatment. The percent recoveries ranged between 91.3 and 117.9%.


Asunto(s)
Cromatografía por Intercambio Iónico/métodos , Peces , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Histamina/análisis , Histidina/análisis , Animales , Histamina/química , Histidina/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...