Wessling International Research and Educational Center

Budapest, Hungary

Wessling International Research and Educational Center

Budapest, Hungary
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Bodai Z.,Eötvös Loránd University | Jakab P.P.,Eötvös Loránd University | Novak M.,Eötvös Loránd University | Nyiri Z.,Eötvös Loránd University | And 4 more authors.
Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment | Year: 2016

Solubility values for six UV stabilisers (Cyasorb UV-1164, Tinuvin P, Tinuvin 234, Tinuvin 326, Tinuvin 327 and Tinuvin 1577) and five antioxidants (Irgafos 168, Irganox 1010, Irganox 3114, Irganox 3790 and Irganox 565) were determined in all the liquid food simulants (3% (m/V) acetic acid–water mixture, 10% (V/V), 20% (V/V), 50% (V/V) ethanol–water mixture and vegetable oil) proposed in European Union Regulation No. 10/2011/EC, as well as in fruit juice and cola drink. The applied method was obtained by modification of the method for the determination of water solubility as described in OECD guideline Test No. 105. By using ultrasonication and shorter equilibration time, the time demand of the solubility determinations were decreased notably. Solubility values proved to be lower than the specific migration limits (as specified in 10/2011/EC) at 25°C for almost all target compounds in food simulants A, B, C and D1 as well as in fruit juice and cola drink. The exceptions were Tinuvin P and Irganox 3790 in simulant D1. The solubility in food simulant D2 was higher than 1000 µg ml–1 for all target compounds. These results show that the solubility of some additives in food simulants can be so low that it makes migration studies for certain additive–food simulant pairs dispensable. © 2016 Taylor & Francis


Novak M.,Eötvös Loránd University | Kirchkeszner C.,Eötvös Loránd University | Palya D.,Eötvös Loránd University | Bodai Z.,Eötvös Loránd University | And 6 more authors.
International Journal of Environmental Analytical Chemistry | Year: 2015

Solid-state urea clathrate formation (SSUCF) as a chemical separation method prior to stable carbon isotope fingerprinting of diesel fuel contaminations was studied. The stable carbon isotope ratios (δ13C) of n-alkanes in diesel fuel can be used to trace the origin of a contamination. The accurate measurement of the stable isotopic composition of individual compounds requires baseline separation from any other co-eluting compounds. For this purpose silica gel column chromatography (SGCC) and SSUCF were applied. Detailed optimisation of SSUCF was performed: different activators, clathrate formation temperatures, activator volumes, clathrate formation times and sample capacity were investigated. The main benefits of the developed method are reduced clathrate formation time and increased recoveries for lower molecular weight n-alkanes. The recoveries of the developed SSUCF method ranged between 63 and 100% for C10–C24 n-alkanes with relative standard deviation no more than 7%. The precision of the gas chromatography-isotope ratio mass spectrometry measurement was acceptable with a standard deviation of the δ13C values ranging between 0.08 and 0.15‰. The absence of isotopic fractionation was also investigated. The robustness of the method was tested within a model experiment. Nine different water samples including distilled water, tap water, river water, industrial wastewaters and groundwater samples were spiked with the same diesel fuel. The water samples were extracted with n-hexane and after purification with both SGCC and SSUCF n-alkanes were measured. The δ13C values of n-alkanes were found to be similar for all samples. The importance of sample purification prior to compound-specific isotope analysis (CSIA) was also demonstrated within this model experiment by analysing samples from different stages of the sample preparation. Our results show that the proposed method can remarkably improve the precision of compound-specific stable carbon isotope analysis of n-alkanes originating from diesel contamination of the aquatic environment. © 2015 Taylor & Francis.


Bodai Z.,Eötvös Loránd University | Kirchkeszner C.,Eötvös Loránd University | Novak M.,Eötvös Loránd University | Nyiri Z.,Eötvös Loránd University | And 6 more authors.
Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment | Year: 2015

Migration of Tinuvin P (UV stabiliser) and Irganox 3114 (antioxidant) from high-density polyethylene (HDPE) was studied. HDPE pieces were soaked in either milk (1.5% or 3.5% fat content) or 50% (v/v) ethanol–water mixture – the food simulant for milk as specified in Regulation No. 10/2011/EC. The obtained extracts were analysed by LC-MS/MS. For statistical assessment variography was used. It proved to be a useful tool for making a distinction between the early migration range and the equilibrium, despite the variance of the data. Regulation No. 10/2011/EC specifies 10 days of contact time for milk at 5°C. Our experiments with the food simulant with 24 dm2 kg−1 surface/mass ratio showed that both Tinuvin P and Irganox 3114 need less than 1 h to reach equilibrium. Furthermore, 10-day experiments with daily sampling showed that these additives are stable in milk, as well as in the food simulant. The effect of the concentration of the additives in HDPE was studied in the 0.01–5% (m/m) range. For both Tinuvin P and Irganox 3114 and all three extractants the migrated amount became independent of the concentration of the additive in the HDPE approximately at 1% (m/m). For Tinuvin P the food simulant gave a close estimate for the milk samples. However, using the food simulant for modelling the migration of Irganox 3114 into milk gave an overestimation with a factor of minimum 3.5. In the case of Tinuvin P special care must be taken, since the recommended amount in the HDPE can result in additive concentrations near or even over the specific migration limit (SML). However, Irganox 3114 cannot reach the SML either in milk or in the food simulant. © 2015 Taylor & Francis.


Bodai Z.,Eötvös Loránd University | Szabo B.S.,Eötvös Loránd University | Novak M.,Eötvös Loránd University | Hamori S.,Eötvös Loránd University | And 4 more authors.
Journal of Agricultural and Food Chemistry | Year: 2014

A simple and fast analytical method was developed for the determination of six UV stabilizers (Cyasorb UV-1164, Tinuvin P, Tinuvin 234, Tinuvin 326, Tinuvin 327, and Tinuvin 1577) and five antioxidants (Irgafos 168, Irganox 1010, Irganox 3114, Irganox 3790, and Irganox 565) in milk. For sample preparation liquid-liquid extraction with low-temperature purification combined with centrifugation was used to remove fats, proteins, and sugars. After the cleanup step, the sample was analyzed with high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). External standard and matrix calibrations were tested. External calibration proved to be acceptable for Tinuvin P, Tinuvin 234, Tinuvin 326, Tinuvin 327, Irganox 3114, and Irganox 3790. The method was successfully validated with matrix calibration for all compounds. Method detection limits were between 0.25 and 10 μg/kg. Accuracies ranged from 93 to 109%, and intraday precisions were <13%. © 2014 American Chemical Society.


Nasz S.,Eötvös Loránd University | Karolyne E.M.,Alfoldi Tej Kft | Rikker T.,Wessling International Research and Educational Center | Eke Z.,Eötvös Loránd University | Eke Z.,Wessling International Research and Educational Center
Chromatographia | Year: 2012

A liquid chromatographic tandem mass spectrometric (LC-MS-MS) method for the determination of five chemical coccidiostats (decoquinate, diclazuril, halofuginone, nicarbazin, and robenidine) and five ionophore coccidiostats (maduramicin, monensin, narasin, salinomycin, and semduramicin) in yoghurt, kefir, and sour cream is presented. Lasalocid, the sixth ionophore listed in 124/2009/EC was not included because of its extremely dissimilar behavior during sample preparation. Main steps of the method include extraction with acetonitrile, centrifugation, clean-up on Oasis HLB solid phase extraction cartridge, evaporation under nitrogen stream, and LC-MS-MS determination. Selectivity, linearity, sensitivity, accuracy, repeatability, within-laboratory reproducibility, limit of determination, and limit of quantitation were determined during the validation procedure. The method proved to be applicable for both qualitative and quantitative determination of the ten above-mentioned target compounds. In our in-house fermentation experiments, milk fortified with coccidiostats was fermented to get yoghurt, kefir, and sour cream. Our results show that the coccidiostat content did not change significantly during fermentation for any of the target compounds. © Springer-Verlag 2012.


Nasz S.,Eötvös Loránd University | Debreczeni L.,Feed Investigation National Reference Laboratory | Rikker T.,Wessling International Research and Educational Center | Eke Z.,Eötvös Loránd University | Eke Z.,Wessling International Research and Educational Center
Food Chemistry | Year: 2012

A reversed phase liquid chromatographic-tandem mass spectrometric method with simple solvent extraction and purification by solid phase extraction (SPE) has been developed for the determination of coccidiostats in milk. For sample preparation matrix solid phase dispersion, extraction by organic solvent and SPE with different cartridges were also tested. The compounds determined include lasalocid, narasin, salinomycin, monensin, semduramicin, maduramicin, robenidine, decoquinate, halofuginone, nicarbazin and diclazuril. Main steps of the method are addition of acetonitrile to the milk samples, centrifugation, removal of matrix by SPE, concentration by evaporation and LC-MS-MS determination. During a 15 min time segmented chromatographic run compounds are ionised either positively or negatively. Calculated recoveries range between 77.1% and 118.2%. Maximum levels are in the range of 1-20 μg/kg. The developed method was validated in line with the requirements of Commission Decision 2002/657/EC (2002). It is applicable for control of coccidiostat residues in milk as indicated in Regulation 124/2009/EC (2009). © 2012 Elsevier Ltd. All rights reserved.


PubMed | Wessling International Research and Educational Center, Eötvös Loránd University and Feed Investigation National Reference Laboratory
Type: Journal Article | Journal: Food chemistry | Year: 2015

A reversed phase liquid chromatographic-tandem mass spectrometric method with simple solvent extraction and purification by solid phase extraction (SPE) has been developed for the determination of coccidiostats in milk. For sample preparation matrix solid phase dispersion, extraction by organic solvent and SPE with different cartridges were also tested. The compounds determined include lasalocid, narasin, salinomycin, monensin, semduramicin, maduramicin, robenidine, decoquinate, halofuginone, nicarbazin and diclazuril. Main steps of the method are addition of acetonitrile to the milk samples, centrifugation, removal of matrix by SPE, concentration by evaporation and LC-MS-MS determination. During a 15 min time segmented chromatographic run compounds are ionised either positively or negatively. Calculated recoveries range between 77.1% and 118.2%. Maximum levels are in the range of 1-20 g/kg. The developed method was validated in line with the requirements of Commission Decision 2002/657/EC (2002). It is applicable for control of coccidiostat residues in milk as indicated in Regulation 124/2009/EC (2009).

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