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See detailFuran Formation from Lipids in Starch-Based Model Systems, As Influenced by Interactions with Antioxidants and Proteins.
Owczarek-Fendor, A.; De Meulenaer, B.; Scholl, Georges ULg et al

in Journal of Agricultural and Food Chemistry (2011), 59(6), 2368-2376

The formation of furan upon sterilization of a lipid-containing starch gel was investigated in the presence of various antioxidants, namely, alpha-tocopherol, beta-carotene, and ascorbic acid, with and ... [more ▼]

The formation of furan upon sterilization of a lipid-containing starch gel was investigated in the presence of various antioxidants, namely, alpha-tocopherol, beta-carotene, and ascorbic acid, with and without proteins. Results indicated that alpha-tocopherol did not significantly influence furan formation from oxidized lipids. beta-Carotene, suggested previously to be a furan precursor itself, did influence the generation of furan in a concentration-dependent manner, although to a limited extent. Surprisingly, the presence of lipids seemed to limit the furan generation from beta-carotene. Interestingly, the addition of ascorbic acid to the emulsions containing soybean or sunflower oils considerably enhanced the formation of furan from these oils. This was also the case when fresh oils were applied, shown previously to be nearly unable to generate furan. This observation can be explained by an intensified ascorbic acid degradation stimulated by the presence of lipids. [less ▲]

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See detailFuran formation in baby food model system via lipid oxidation and sugar degradation
Owczarek-Fendor, Agnieszka; De Meulenaer, Bruno; Scholl, Georges ULg et al

in Communications in Agricultural and Applied Biological Sciences (2011), 76(1), 107-110

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See detailDioxins in Human Milk from Different Regions of France: Pilot of the French Longitudinal Study of Children (ELFE)
Vandentoren, S; Frery, N; Bidondo, ML et al

in Organohalogen Compounds (2011), 73

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See detailPLE for extraction of dioxins in animal feed and ingredients
Focant, Jean-François ULg; Scholl, Georges ULg; De Pauw, Edwin ULg et al

in Organohalogen Compounds (2010, September), 72

Within the entire complex procedure required to measure dioxins and related compounds in biological matrices, the extraction step is often seen as a well controlled step. Although maybe true for many ... [more ▼]

Within the entire complex procedure required to measure dioxins and related compounds in biological matrices, the extraction step is often seen as a well controlled step. Although maybe true for many human and food-related matrices, the situation is very different for animal feed and feed ingredients. Specific European guidelines (e.g. Commission Directive 2006/13/EC, Commission Regulation (EC) No 152/2009) exist for animal feed but only list general requirements for the various stages of the procedure. The liberty is left to laboratories to select, for example, the tools used for the extraction steps. This has the advantage to allow ‘in-house’ methods to be used, as long as they satisfy with all the requirements of the EU Regulation. In that context, it is foreseen that the European Committee for Standardization (CEN) will soon propose a standard for the determination of PCDD/Fs and PCBs in animal feed that would be the reference method to be used to solve potential issues in case of dispute over results reported from different laboratories. A major point of concern is that it has been reported earlier1 that most commonly accepted extraction procedure can conduct to significantly different results for the extraction of dioxins and related compounds in feed and feed additives such as mineral clays and various oxides. Several non-instrumental and instrumental automated approaches are available for extraction. Soxhlet extractors have long been the most used tools for non-instrumental extraction of solids. They have proven to be very efficient but some limitations encouraged the development of other approaches based on instrumental techniques. For feed extraction, pressurized liquid extraction (PLE) (also branded as accelerated solvent extraction ASE®) is the technique of choice for high sample throughput. This study reports on the investigation of the use of various solvent mixtures, extraction temperatures, and instruments (parallel PLE, sequential ASE®) for the extraction of 17 PCDD/Fs and 12 dioxin-like PCBs in mineral clay, bovine feed, fish meal, and in-house quality control animal compound feed. [less ▲]

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See detailFuran formation from vitamin C in a starch-based model system: Influence of the reaction conditions
Owczarek-Fendor, Agnieska; De Meulenaer, Bruno; Scholl, Georges ULg et al

in Food Chemistry (2010), 121(4), 1163-1170

The generation of furan from vitamin C during thermal treatment of a starch-based model system, which simulated baby food, was studied. Results indicated that the amount of sample heated in the vial ... [more ▼]

The generation of furan from vitamin C during thermal treatment of a starch-based model system, which simulated baby food, was studied. Results indicated that the amount of sample heated in the vial influenced the furan generation from ascorbic acid. Increasing the amount of heated sample from 5% to approximately 98% of the total vial volume, drastically reduced furan formation from 70 ppb to 16 ppb. Changes in ascorbic acid concentrations from 0.1 to 4.5 mg/g did not influence furan concentration nor did different ascorbic/dehydroascorbic acid molar ratios. Interestingly, waxy corn starch itself considerably enhanced furan generation from ascorbic acid. Under the same conditions, 13.2 ppb of furan was generated in starch-based samples, while in ascorbic acid buffered solutions only 0.4 ppb of furan was formed. Application of other matrices, in particular agar and hydrolysed starch, resulted in similar furan concentrations as for native starch, while in polyol solutions furan concentrations were comparable to those obtained for the buffered ascorbic acid solutions. [less ▲]

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See detailFuran formation in baby food model systems from vitamin C and unsaturated fatty acids
Owczarek-Fendor, Agnieszka; De Meulenaer, Bruno; Scholl, Georges ULg et al

Conference (2010)

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See detailImportance of fat oxidation in starch-based emulsions in the generation of the process contaminant furan.
Owczarek-Fendor, Agnieszka; De Meulenaer, Bruno; Scholl, Georges ULg et al

in Journal of Agricultural and Food Chemistry (2010), 58(17), 9579-86

The formation of the possibly carcinogenic process contaminant furan was studied in starch-based emulsions during heat treatments as applied for sterilization. Fresh and oxidized soybean, sunflower, high ... [more ▼]

The formation of the possibly carcinogenic process contaminant furan was studied in starch-based emulsions during heat treatments as applied for sterilization. Fresh and oxidized soybean, sunflower, high-oleic sunflower, olive, linseed, and rapeseed oils were compared. Results indicated that both the oil type, in particular, the fatty acid composition, and the oxidation degree of the oil determined the susceptibility of the oils to generate furan upon heating. Thus, oils containing the nutritionally relevant omega-3 unsaturated alpha-linolenic acid proved to be able to generate significant amounts of furan if the oils were oxidized. No clear relationship between p-anisidine values of various oils and the amount of generated furan could be observed. However, in the case of soybean oil, significantly more furan was produced upon an increase in oxidation degree. Surprisingly, furan formation in food-relevant systems containing fresh lipids proved to be a minor route (up to 1.5 ppb furan) compared to a previously studied vitamin C containing model system (up to 13 ppb furan). [less ▲]

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See detailPersistent organochlorine pollutants, dioxins and polychlorinated biphenyls
Scippo, Marie-Louise ULg; Eppe, Gauthier ULg; Saegerman, Claude ULg et al

in Contaminant and Residue Analysis, Comprehensive Analytical Chemistry of Elsevier (2008)

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See detailAnalysis of furan by GC/MS
Scholl, Georges ULg; Eppe, Gauthier ULg; Scippo, Marie-Louise ULg et al

Poster (2007)

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See detailHigh-throughput biomonitoring of dioxins and polychlorinated biphenyls at the sub-picogram level in human serum
Focant, Jean-François ULg; Eppe, Gauthier ULg; Massart, Anne-Cécile ULg et al

in Journal of Chromatography. A (2006), 1130(1), 97-107

We report on the use of a state-of-the-art method for the measurement of selected polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated biphenyls in human serum specimens ... [more ▼]

We report on the use of a state-of-the-art method for the measurement of selected polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated biphenyls in human serum specimens. The sample preparation procedure is based on manual small size solid-phase extraction (SPE) followed by automated clean-up and fractionation using multi-sorbent liquid chromatography columns. SPE cartridges and all clean-up columns are disposable. Samples are processed in batches of 20 units, including one blank control (BC) sample and one quality control (QC) sample. The analytical measurement is performed using gas chromatography coupled to isotope dilution high-resolution mass spectrometry. The sample throughput corresponds to one series of 20 samples per day, from sample reception to data quality cross-check and reporting, once the procedure has been started and series of samples keep being produced. Four analysts are required to ensure proper performances of the procedure. The entire procedure has been validated under International Organization for Standardization (ISO) 17025 criteria and further tested over more than 1500 unknown samples during various epidemiological studies. The method is further discussed in terms of reproducibility, efficiency and long-term stability regarding the 35 target analytes. Data related to quality control and limit of quantification (LOQ) calculations are also presented and discussed. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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