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Relationship between arsenic content of food and water applied for food processing Texto completo
2013
Sugár, Éva | Tatár, Enikő | Záray, Gyula | Mihucz, Victor G.
As part of a survey conducted by the Central Agricultural Office of Hungary, 67 food samples including beverages were taken from 57 food industrial and catering companies, 75% of them being small and medium-sized enterprises (SMEs). Moreover, 40% of the SMEs were micro entities. Water used for food processing was simultaneously sampled. The arsenic (As) content of solid food stuff was determined by hydride generation atomic absorption spectrometry after dry ashing. Food stuff with high water content and water samples were analyzed by inductively coupled plasma mass spectrometry. The As concentration exceeded 10μg/L in 74% of the water samples taken from SMEs. The As concentrations of samples with high water content and water used were linearly correlated. Estimated As intake from combined exposure to drinking water and food of the population was on average 40% of the daily lower limit of WHO on the benchmark dose for a 0.5% increased incidence of lung cancer (BMDL0.5) for As. Five settlements had higher As intake than the BMDL0.5. Three of these settlements are situated in Csongrád county and the distance between them is less than 55km. The maximum As intake might be 3.8μg/kg body weight.
Mostrar más [+] Menos [-]Simultaneous determination of water soluble vitamins in fortified food products Texto completo
2010
Engel, R. | Abrankó, L. | Stefanovits-Bányai, É | Fodor, P.
Vitamins form a heterogeneous chemical group having different stability. In foodstuffs some of them might be bound to matrix components. In the case of vitamin supplemented food products, since the vitamins are not strongly embedded in the matrix a general extraction method could be fit for purpose. The aim of this study was the simultaneous determination of the most common water-soluble vitamins, i.e. ascorbic acid (C), riboflavin (B <sub>2</sub>), niacin (B <sub>3</sub>), pyridoxine (B <sub>6</sub>), folic acid (B <sub>9</sub>) in enriched food products. Sample preparation based on the European Standard (CEN, 2003) was optimised for further LC-MS compatible chromatography. The separation of the vitamins was achieved by reversed-phase liquid chromatography. Detection was carried out with a photodiode array detector at four different wavelengths. The chromatographic method and the sample preparation were successfully applied for vitamin-enriched cereal, instant cacao powder and fruit juice samples.
Mostrar más [+] Menos [-]Perchlorate as an emerging contaminant in soil, water and food Texto completo
2016
Kumarathilaka, Prasanna | Oze, Christopher | Indraratne, S.P. | Vithanage, Meththika
Perchlorate (ClO4−) is a strong oxidizer and has gained significant attention due to its reactivity, occurrence, and persistence in surface water, groundwater, soil and food. Stable isotope techniques (i.e., (18O/16O and 17O/16O) and 37Cl/35Cl) facilitate the differentiation of naturally occurring perchlorate from anthropogenic perchlorate. At high enough concentrations, perchlorate can inhibit proper function of the thyroid gland. Dietary reference dose (RfD) for perchlorate exposure from both food and water is set at 0.7 μg kg−1 body weight/day which translates to a drinking water level of 24.5 μg L−1. Chromatographic techniques (i.e., ion chromatography and liquid chromatography mass spectrometry) can be successfully used to detect trace level of perchlorate in environmental samples. Perchlorate can be effectively removed by wide variety of remediation techniques such as bio-reduction, chemical reduction, adsorption, membrane filtration, ion exchange and electro-reduction. Bio-reduction is appropriate for large scale treatment plants whereas ion exchange is suitable for removing trace level of perchlorate in aqueous medium. The environmental occurrence of perchlorate, toxicity, analytical techniques, removal technologies are presented.
Mostrar más [+] Menos [-]Microplastics and nanoplastics in food, water, and beverages, part II. Methods Texto completo
2022
Vitali, Clementina | Peters, Ruud J.B. | Janssen, Hans Gerd | Nielen, Michel W.F. | Ruggeri, Francesco Simone
Since microplastics (MPs) and nanoplastics (NPs) have started emerging as ubiquitous contaminants in the environment, a variety of analytical techniques has been developed and tested for the detection and characterization of polymer particles at a micro- and nano-scale. Yet, no unique method stands out for its ability to yield all the relevant information required to properly address MP and NP contamination in the environment, and even less so in food material. In this review, several approaches to sample preparation and isolation of MPs from food matrices are reported, well-established and promising emerging analytical techniques for the detection and characterization of MPs and NPs are described and discussed. The information reported in this review shows that even the most widely used methods are still under development and MP/NP analysis is still far away from method validation and standardization. The establishment of rigorous best practices to yield reliable data and build a comprehensive knowledge of MP and NP occurrence in food is essential for the implementation of strategies and policies to address MP/NP pollution. Therefore, an outlook of the field towards harmonization and quality improvement of MP/NP analysis is included in this review.
Mostrar más [+] Menos [-]Halimione portulacoides biomass - a sustainable feedstock for bioenergy production from an integrated water-energy-food system Texto completo
2022
Coimbra, Ricardo N. | Custódio, Marco | Cuerda-Correa, Eduardo M. | Ali Khan, Moonis | Calado, Ricardo | Lillebø, Ana I. | Otero, Marta
In view of a water-energy-food (WEF) nexus strategy, the present work assessed the bioenergy production potential of Halimione portulacoides used for the phytoremediation of nutrient-rich simulated wastewater from saltwater-based integrated multi-trophic aquaculture (IMTA). Specimens of this halophyte plant were grown in hydroponics under four different nutrient treatments with distinct nitrogen (N) and phosphorous (P) concentrations. Ultimate and proximate analysis, calorific value and thermogravimetric analysis coupled to mass spectrometry were used to assess the bioenergy potential of the non-edible biomass of the plants, namely the canes (C) and roots (R), and of commercial pellets (CP), which were used as benchmark. R and, especially, CP had higher carbon but lower oxygen content and larger volatiles but lower ashes than C. The higher heating values (HHV) of C (16–17 MJ kg⁻¹) and R (17–18 MJ kg⁻¹) were the same order as those of conventional energy crops and CP (20 MJ kg⁻¹). Although mass loss and associated gaseous emissions during temperature programmed pyrolysis occurred mainly between 250 and 650 °C for all biomasses, they took place at slightly higher temperatures for C > CP > R. In any case, the integrated gaseous emissions during the pyrolysis of C, R, and CP were very similar and included H₂, CH₄, CO, and CO₂ (syngas main constituents). Biomass production of C was affected by the nutrients load of the applied treatments, but this was not the case for R. Also, the nutrients treatments had no detectable effects on the biomasses’ ultimate or proximate analysis, HHV, thermal decomposition or resultant gaseous emissions. Thermal properties and behaviour of C and R were very similar to those of CP, showing their potential for bioenergy production and revealing that a WEF nexus strategy can be implemented in IMTA by energetic valorization of non-edible biomass of H. portulacoides used for water phytoremediation.
Mostrar más [+] Menos [-]A highly sensitive and selective fluorescent probe for quantitative detection of Al³⁺ in food, water, and living cells Texto completo
2019
Jiang, Qian | Li, Mingxin | Song, Jie | Yang, Yiqin | Xu, Xu | Xu, Haijun | Wang, Shifa
Three novel β-pinene-based fluorescent probes 2a–2c were designed and synthesized for the selective detection of Al³⁺. Probe 2a showed higher fluorescence intensity toward Al³⁺ than the other two compounds. Probe 2a determined the concentration of Al³⁺ with a rapid response time (45 s), wide pH range (pH = 1–9), excellent sensitivity (LOD = 8.1 × 10⁻⁸ M) and good selectivity. The recognition mechanism of probe 2a toward Al³⁺ was confirmed by ¹H NMR, HRMS and DFT analysis. Probe 2a was successfully used as a signal tool to quantitatively detect Al³⁺ in food samples and environmental water samples. Furthermore, probe 2a was successfully utilized to label intracellular Al³⁺, indicating its promising applications in living cells.
Mostrar más [+] Menos [-]Modeling for Survival of Clostridium perfringens in Saeng-sik,a Powdered Ready-to-Eat Food with Low Water Activity Texto completo
2019
Park, Jin Hwa | Koo, Min Seon | Kim, Hyun Jung
Saeng-sikis a powdered ready-to-eat food with very low moisture that contains dried raw materials such as grains, fruits,mushrooms, and seaweeds. This product is consumed as a convenient and nutritious meal replacement. The objective of this study was to develop a mathematical model for predicting the survival of Clostridium perfringens vegetative cells and spores in saeng-sikas a function of temperature and to validate the model using saeng-siksamples with different microbial communities analyzed by matrix-assisted laser desorptionionization time-of-flight mass spectrometry. Kinetic data for C. perfringens survival in saeng-sikfit well to the Weibull model with high goodness off it (R(2) = 0.92 to 0.98). The obtained δ values (required time for first decimal reduction) for each temperature were 19.62 to 864.86 h, and concave curves (p < 1) were observed under all experimental conditions (5 to 40 degree C). Kinetic parameters were further described in a secondary model as a function of temperature using a Davey model (R(2) =0.99). The developed model was validated by the bias factor, accuracy factor, and root mean square error, and the values were within acceptable ranges for predictive models, even for saeng-sik samples with different microbial communities. When saeng-sikwas rehydrated according to the manufacturer’s recommendations, germination and outgrowth of C. perfringens was observed when the sample was subjected to unusual temperatures during storage, such as at 30 degree C for 15 h. C. perfringens spores survived in saeng-sik with very low water activity. Because C. perfringens could germinate and grow under such conditions, care must be taken to avoid initial contamination of C. perfringens during the manufacturing process. Our model developed with samples with different microbial communities provides useful information for next-generation microbiological risk assessment taking into consideration the ecology of the food-associated microbial community.
Mostrar más [+] Menos [-]Analysis of antibiotics and PFAS as potential emerging pollutants in the water bodies and their accumulation in food samples Texto completo
2021
Mpela, Ntshani Gershom | Tavengwa, N. T.
MSc (Chemistry) | Department of Chemistry | Antibiotics and perfluoroalkyl substances (PFAS) are groups of anthropogenic substances that are found in industries and consumer products, i.e., antibiotics are used in healthcare facilities, pharmaceutical companies, and agriculture, whereas PFAS are used in industries and households. These compounds find their way into the environment through emission, landfill disposal, agricultural run-offs, irrigations, leaching and wastewater spillage. Their residues are widely detected in almost every environmental compartment. Their detection in drinking water and food is one of the global concerns. Their effect in living organisms have been widely documented ranging from allergic reaction to carcinogenic effect, and in serious situations they can lead to death. In this project, the background review on the behaviour of antibiotics and PFAS in different environments are discussed in chapter two. This has been done by looking into their physico-chemical properties, distribution pathways, accumulation and toxicity in various environmental compartments through available literature. After understanding their behaviour in the environment two review papers, namely Paper I and Paper II, were written. Paper I was a book chapter which focused on the application of miniaturised liquid phase extraction techniques used for extraction of antibiotics in environmental water samples. In this book chapter, the use of liquid-liquid extraction techniques was discussed and the evolution of liquid-liquid extraction technique into miniaturised extraction technique was reviewed. Paper II was a critical review which focuses on the application of dispersive liquid-liquid micro-extraction of PFAS in different environmental samples. In this paper, the principles of dispersive liquid-liquid micro-extraction was explained. Later, its application for pre-concentration of PFAS was reviewed and the future trends were discussed. In chapter four, three lab-based papers, namely Paper III, Paper IV and Paper V, were written. In Paper III, for the first time a dispersive liquid-liquid microextraction technique was developed and applied for extraction of multi-class antibiotics in macadamia nuts prior to UHPLC-qToF-MS analysis. In paper IV, a novel deep eutectic solvent was synthesised and characterised using FTIR spectroscopy. For the first time the synthesised deep eutectic solvent was applied for extraction of multiclass antibiotics in green beans prior to UHPLC-qToF-MS analysis. In Paper V, for the first a dispersive liquid-liquid micro-extraction technique was developed and applied for extraction of PFAS in food contact materials prior to UHPLC-qToF-MS analysis. Owing to their ease of operation, efficiency and sensitivity, these techniques can also be applied for preconcentration of antibiotics and PFAS in different food, environmental and biological samples. | NRF
Mostrar más [+] Menos [-]Identification of Cationic and Anionic Surfactants by Chromatography–Mass-Spectrometry in the Microextraction–Fluorimetry Screening of Water and Food Products Texto completo
2021
Amelin, V. G. | Shogah, Z. A. Ch | Bol’shakov, D. S.
A method is proposed for the identification of surfactants by ultra-performance liquid chromatography (UPLC) with high-resolution mass spectrometry detection after screening water and food samples for the total concentration of cationic and anionic surfactants by microextraction–fluorimetry. The method is based on the use of dispersive liquid–liquid microextraction with chloroform of surfactant ion pairs with organic reagents (eosin and acridine yellow), measuring the fluorescence of the obtained adducts using a smartphone, obtaining RGB colorimetric characteristics, and determining the total surfactant concentration. The main analytical characteristics of the identification of cationic surfactants (alkylpyrdinium, alkyltrimethylammonium, alkyldimethylbenzylammonium (benzalkonium), alkylmethylethylbenzylammonium, didecyldimethylammonium, benzyldimethyl[3-(myristoylamino)propyl]ammonium, N,N-bis(3-aminopropyl)dodecylamine chlorides) and anionic surfactants (alkyl benzene sulfonates (sulfonol), alkyl sulfates, laureth sulfates, alkyl sulfonates, and sodium alkyl carboxylates) by chromatography–mass spectrometry under the selected conditions of chromatographic separation and mass spectrometric detection are found. The features of the chromatographic behavior of the surfactant polymerhomologs under the conditions of UPLC and gradient elution are considered.
Mostrar más [+] Menos [-]Absolute quantification of norovirus capsid protein in food, water, and soil using synthetic peptides with electrospray and MALDI mass spectrometry Texto completo
2015
Hartmann, Erica M. | Colquhoun, David R. | Schwab, Kellogg J. | Halden, Rolf U.
Norovirus infections are one of the most prominent public health problems of microbial origin in the U.S. and other industrialized countries. Surveillance is necessary to prevent secondary infection, confirm successful cleanup after outbreaks, and track the causative agent. Quantitative mass spectrometry, based on absolute quantitation with stable-isotope labeled peptides, is a promising tool for norovirus monitoring because of its speed, sensitivity, and robustness in the face of environmental inhibitors. In the current study, we present two new methods for the detection of the norovirus genogroup I capsid protein using electrospray and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The peptide TLDPIEVPLEDVR was used to quantify norovirus-like particles down to 500 attomoles with electrospray and 100 attomoles with MALDI. With MALDI, we also demonstrate a detection limit of 1 femtomole and a quantitative dynamic range of 5 orders of magnitude in the presence of an environmental matrix effect. Due to the rapid processing time and applicability to a wide range of environmental sample types (bacterial lysate, produce, milk, soil, and groundwater), mass spectrometry-based absolute quantitation has a strong potential for use in public health and environmental sciences.
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