References of "Blecker, Christophe"
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See detailInteresterification of rapeseed oil with anhydrous milk fat and its stearin fraction
Giet, Jean-Michel ULg; Aguedo, Mario ULg; Hanon, Emilien ULg et al

Poster (2009)

The compositional changes occurring during the lipase-catalysed interesterification of AMF/rapeseed oil (RO) and AMF stearin fraction (AMFSF)/RO blends were described in the first part of this study. In ... [more ▼]

The compositional changes occurring during the lipase-catalysed interesterification of AMF/rapeseed oil (RO) and AMF stearin fraction (AMFSF)/RO blends were described in the first part of this study. In the present and second part are reported the resulting changes in physical properties, especially the melting behaviour through solid fat content (SFC), dropping point (DP) and fusion profiles by differential scanning calorimetry (DSC). [less ▲]

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See detailEnrichment of Anhydrous Milk Fat in Polyunsatured Fatty Acid Residues
Aguedo, Mario ULg; Hanon, Emilien ULg; Danthine, Sabine ULg et al

Poster (2009)

Lipozyme TL IM was used in a solvent-free batch, microaqueous system for enzymatic interesterification of anhydrous milkfat (AMF) with linseed oil (LO) in binary blends and with rapeseed oil (RO) in one ... [more ▼]

Lipozyme TL IM was used in a solvent-free batch, microaqueous system for enzymatic interesterification of anhydrous milkfat (AMF) with linseed oil (LO) in binary blends and with rapeseed oil (RO) in one ternary blend. [less ▲]

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See detailEffect of surfactants and biomass on the gas/liquid mass transfer in an aqueous-silicone oil two-phase partitioning bioreactor using Rhodococcus erythropolis T902.1 to remove VOCs from gaseous effluents
Aldric, Jean-Marc ULg; Gillet, Sébastien ULg; Delvigne, Frank ULg et al

in Journal of Chemical Technology & Biotechnology (2009), 84

BACKGROUND: The two-phase partitioning bioreactor (TPPB) has become a new strategy in the context of waste gas treatment. However, the impact of biomass and surfactants on gas/liquid (G/L) mass transfer ... [more ▼]

BACKGROUND: The two-phase partitioning bioreactor (TPPB) has become a new strategy in the context of waste gas treatment. However, the impact of biomass and surfactants on gas/liquid (G/L) mass transfer needs to be better evaluated because the impact of these factors on the mass transfer coefficient “ ” and the interfacial area “ ”, respectively, remains misunderstood. RESULTS: Our study showed that, firstly, the surfactant extract produced by Rhodococcus erythropolis reduced the surface hydrophobicity of the biomass. Secondly, an optimal concentration appeared to exist for both of the components, respectively 0.5 g.L-1 and 0.7 g.L-1 for biomass (B) and surfactant extract (SE) when the global mass transfer coefficient ( ) of oxygen was measured in a silicone oil/water TPPB. However, the combination of B and SE was found to induce a negative synergism. In particular, SE improved the interfacial area “ ” by increasing the bubble diameter, while B reduced it as soon as a concentration of 1g.L-1 was exceeded. By contrast, the SE acted negatively on the , while B improved it overall. CONCLUSION: Better consideration is needed of the effect of biotic components in order to understand the phenomenon of G/L mass transfer in a TPPB. The behaviour of biomass growth and surfactants may strongly influence the mathematical models suggested in the literature. [less ▲]

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See detailImpact of the Crystallinity on the Physical Properties of Inulin during Water Sorption
Ronkart, Sebastien N; Paquot, Michel ULg; Blecker, Christophe ULg et al

in Food Biophysics (2009), 4(1), 49-58

The impact of the crystallinity of spray-dried inulins on their stability and physical properties was investigated after a conditioning of 1 week at different relative humidity levels (0% to 94%) at 20 A ... [more ▼]

The impact of the crystallinity of spray-dried inulins on their stability and physical properties was investigated after a conditioning of 1 week at different relative humidity levels (0% to 94%) at 20 A degrees C. An environmental scanning electron microscopy study showed that the amorphous powders hardened at a relative humidity storage between 59% and 75%; while their semi-crystalline counterparts were partially agglomerated but friable in the same conditions. Caking was observed when the glass transition temperature of the amorphous phase of the material dropped below the storage temperature of the powder. It resulted in a crystallization of the structural units of varying lengths composing inulin, but also an increase of the crystallinity of the semi-crystalline ones. This study showed the importance of the crystallinity of inulin on its stability and physical properties during storage which is of crucial importance for the shelf-life of food and pharmaceutical products in the dry state. [less ▲]

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See detailEffect of water uptake on amorphous inulin properties
Ronkart, Sebastien N; Paquot, Michel ULg; Fougnies, Christian et al

in Food Hydrocolloids (2009), 23(3), 922-927

Physical property changes of amorphous spray-dried inulin were investigated during water uptake at 20 degrees C. Modulated Differential Scanning Calorimetry (MDSC) and Wide Angle X-ray Scattering (WAXS ... [more ▼]

Physical property changes of amorphous spray-dried inulin were investigated during water uptake at 20 degrees C. Modulated Differential Scanning Calorimetry (MDSC) and Wide Angle X-ray Scattering (WAXS) were used to investigate the evolution of the glass transition temperature (T-g) and the crystallinity index, respectively. The water content, crystallization and thermal properties relationship enabled the identification of three zones in the T-g-water content state diagram. Zone I delimited inulin in a glassy amorphous state, while zone II characterized inulin in a liquid amorphous state. Inulin crystallized and caked when T-g was below the storage temperature of 20 degrees C, but crystallization (zone III) was not spontaneous and was delayed by the defined zone II. The crystallization led to thermograms with an endotherm close to T-g. Temperature-Resolved WAXS allowed to correctly ascertain the MDSC endothermic peak as a melting peak because the crystallinity index was maximal at onset temperature of the transition, and dropped to zero at the endset temperature. (C) 2008 Elsevier Ltd. All rights reserved. [less ▲]

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See detailOptimization of enzymatic extraction of ferulic acid from wheat bran, using response surface methodology, and characterization of the resulting fractions
Barberousse, Helene; Kamoun, Amel; Chaabouni, Moncef et al

in Journal of the Science of Food and Agriculture (2009), 89(10), 1634-1641

BACKGROUND: The agro-industries generate thousands of tons of by-products, such as bran or pulps, each year. They are, at best, used for cattle feeding. Through biocracking, this biomass may constitute a ... [more ▼]

BACKGROUND: The agro-industries generate thousands of tons of by-products, such as bran or pulps, each year. They are, at best, used for cattle feeding. Through biocracking, this biomass may constitute a renewable source for various molecules of interest for the industry. For instance, ferulic acid, a compound showing antioxidant ability, is found in abundance in cereal bran. Its release depends mainly on the breaking of its ester linkage to other constitutive elements of the cell wall, such as arabinoxylans. Response surface methodology was used to evaluate the effects of ferulic acid esterase (FAE) and xylanase activities, as well as incubation time and temperature, on ferulic acid extraction yield from wheat bran. Under optimized conditions, the composition of the hydrolysate and of residual bran were compared to native bran. RESULTS: Experiments carried out under the predicted optimal conditions (FAE amount, 27 U g(-1); xylanase amount, 304 U g(-1); incubation time, 2 h; and temperature, 65 degrees C) led to an extraction yield of 52.8%, agreeing with the expected value (51.0%). The crude ferulic acid fraction was purified with Amberlite XAD16, leading to a final concentration of 125 mu g mL(-1) of ferulic acid in ethanol. The antioxidant capacity of this purified fraction was evaluated by the DPPH. scavenging method: it exhibited better efficiency (EC50 = 10.6 mu mol L-1 in ferulic acid) than the ferulic acid standard (EC50 = 13.7 mu mol L-1). CONCLUSION: These results confirm the potential of wheat bran valorization in the field of natural antioxidant extraction, possibly viable in an industrial scheme. (C) 2009 Society of Chemical Industry [less ▲]

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See detailCompositional, Physical, Antioxidant and Sensory Characteristics of Novel Syrup from Date Palm (Phoenix dactylifera L.)
Ben Thabet, I.; Besbes, S.; Masmoudi, M. et al

in Food Science & Technology International (2009), 15(6), 583-590

This study is a contribution to valorise date palm sap (Phoenix dactylifera L.) by elaboration of high quality syrup. Sap was concentrated by evaporation and the obtained product was characterized by its ... [more ▼]

This study is a contribution to valorise date palm sap (Phoenix dactylifera L.) by elaboration of high quality syrup. Sap was concentrated by evaporation and the obtained product was characterized by its physicochemical, rheological, thermal, sensory properties and by its antioxidant activity. Syrups from date palm sap have a good nutritional value marked by high amounts of sugars (58-75 g/100 g fresh matter basis), minerals (2.1-2.6 g/100 g fresh matter basis) and phenolics (147.61-224.55 mg of ferulic acid equivalents/kg fresh weight). Syrup also presents an antioxidant activity that appears related to total phenolic content. Rheological properties indicate that syrup preserves a Newtonian behavior from 10 degrees C to 55 degrees C well modeled by Arrhenius equation. Hedonic evaluation showed that consumers' appreciation of date palm syrup was not significantly different to the most known sap syrup: maple syrup. [less ▲]

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See detailPhysicochemical Characteristics of Date Sap Lagmi from Deglet Nour Palm (Phoenix Dactylifera L.)
Ben Thabet, Imene; Besbes, Souhail; Attia, Hamadi et al

in International Journal of Food Properties (2009), 12(3), 659-670

Physicochemical properties of sap from Deglet Nour date palm (Phoenix dactylifera L.) were studied. Composition analysis revealed (on a dry-weight basis) a high content of carbohydrates (94.98 g/100 g of ... [more ▼]

Physicochemical properties of sap from Deglet Nour date palm (Phoenix dactylifera L.) were studied. Composition analysis revealed (on a dry-weight basis) a high content of carbohydrates (94.98 g/100 g of dry matter basis) mainly sucrose, 2.72 g/100g (dry matter basis) of proteins and 2.29 g/100 g (dry matter basis) of ash. Date palm sap also contains 7.64 mg gallic acid equivalent/100 ml of total polyphenol. Thus, date palm sap showed antioxidant activity with a percentage inhibition of the DPPH radical value of 47.64%. Surface and foaming properties were also performed by drop volume and bubbling method, respectively. Equilibrium surface tension of fresh sap was 63.51 mN/m. Freeze-drying method preserved surface activity. Native sap showed better foam power (1.03) and foam stability (1150 s) than solutions prepared from lyophilised sap (5-30 g /100g of solution). Results demonstrated that this natural juice could be regarded as functional food due to its high nutritional value, antioxidant activity, surface activity, and foam power. [less ▲]

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See detailCalorimetric study of milk fat/rapeseed oil blends and their interesterification products
Aguedo, Mario ULg; Giet, Jean-Michel ULg; Hanon, Emilien ULg et al

in European Journal of Lipid Science and Technology [=EJLST] (2009), 111(4), 376-385

Milk fat (MF) and rapeseed oil (RO) blends were analyzed by differential scanning calorimetry (DSC). It was shown that peak and onset temperatures can be used to determine the percentage of each fat in ... [more ▼]

Milk fat (MF) and rapeseed oil (RO) blends were analyzed by differential scanning calorimetry (DSC). It was shown that peak and onset temperatures can be used to determine the percentage of each fat in the blend and that the relative enthalpy of one peak assigned to low-melting triacylglycerols (TAG) can also be used to determine the percentage of RO in the blend. A linear relation was also established between IMF content of the blend and its dropping point (DP), indicating that DP can be linearly related with the above DSC data. A blend of MF/RO 70 : 30 (wt/wt) was then chosen as a model system for enzymatic interesterification (EIE). The applicability of DSC analyses to EIE products was checked and a correct correlation could be established between DSC values and the interesterification degree and DP. Among the data from the DSC profiles, the peak associated with low-melting TAG was the best indicator of the reaction course. In the same way, a high-melting MF stearin fraction was interesterified. with RO. In that case, onset temperatures and peak "a" were better reaction indicators than for the interesterified MF/RO blend. We therefore suggest that values from DSC endotherms could be used to monitor EIE of fat blends. [less ▲]

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See detailSynthèse et propriétés tensioactives de nouveaux surfactants provenant de matières premières renouvelables.
Laurent, Pascal ULg; Razafindralambo, Hary ULg; Wathelet, Bernard ULg et al

Poster (2009)

A l'heure actuelle, le bioraffinage se présente de plus en plus comme une alternative prometteuse aux filières pétrochimiques puisqu'il vise à la fois le remplacement d'une partie du pétrole comme source ... [more ▼]

A l'heure actuelle, le bioraffinage se présente de plus en plus comme une alternative prometteuse aux filières pétrochimiques puisqu'il vise à la fois le remplacement d'une partie du pétrole comme source d'énergie et le développement de produits chimiques issus de la biomasse (végétale principalement) tels que détergents, produits phytopharmaceutiques, dissolvants, matières plastiques, etc. La valorisation de carbohydrates provenant de matières premières renouvelables fait ainsi actuellement l'objet de nombreuses recherches. Dans ce cadre, la synthèse de nouveaux tensioactifs non ioniques dérivés des acides Dglucuronique et D-galacturonique a été effectuée. [less ▲]

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See detailHigh-throughput methodology applied to screening of carbohydrate-based surfactant interfacial properties for colloidal system formulations
Razafindralambo, Hary ULg; Blecker, Christophe ULg; Deroanne et al

Poster (2009)

Carbohydrate-based surfactants (CBS) constitute an attractive class of amphiphilic molecules owing to their structural diversity generating a wide range of properties which could be developed in food and ... [more ▼]

Carbohydrate-based surfactants (CBS) constitute an attractive class of amphiphilic molecules owing to their structural diversity generating a wide range of properties which could be developed in food and non-food applications. Based on many functional groups of the carbohydrate part, it is possible to design multiple amphiphilic structures of CBS varying in the hydrophilic head groups (mono-, oligo-, or polysaccharides), hydrophobic tail (mono-, di-, tricatenar) but also in the linker/spacer between them. The main structures of CBS include mono- and bicatenar glycolipids, bolaforms, and gemini. Moreover, CBS compounds can be produced from the most abundant renewable materials allowing large product concept possibilities. Among general properties of surfactants, interfacial properties molecules occupy a fundamental key role for colloidal system formulations since they control most of technological aptitudes required for forming and stabilizing food, cosmetic, agrochemical, detergent, and pharmaceutical products. High-throughput methodology applied to screening of CBS interfacial properties appears crucial for achieving optimum formulations of colloidal systems like foams and emulsions for which small amounts of single or mix surface-active agents are often needed and numerous physical and chemical parameters are involved. This general approach may be applied to any amphiphilic molecules produced from other renewable resources of surface-active compounds like micro-organisms and by direct extraction from vegetable materials. One of the key factors for the development of this methodology is the use of automated instrument systems in laboratory scale which are still lacking in this field compared to those existing in the analytical chemistry and biochemistry areas. [less ▲]

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See detailImpacts of the carbonyl group location of ester bond on interfacial properties of sugar-based surfactants: experimental and computational evidences
Razafindralambo, Hary ULg; Blecker, Christophe ULg; Mezdour, Samir et al

in Journal of Physical Chemistry B (2009), 113

Interfacial properties of surfactants are dependent on the conformation adopted by the hydrophilic headgroup or/and the hydrophobic tail at the boundary limit of two immiscible phases. Here, we ... [more ▼]

Interfacial properties of surfactants are dependent on the conformation adopted by the hydrophilic headgroup or/and the hydrophobic tail at the boundary limit of two immiscible phases. Here, we demonstrate the impacts of the carbonyl group (-CO-) location of the ester bond of sugar-based surfactants by comparing some properties of two closely related esters, octyl glucuronate and glucose octanoate, at the air-water interface. The carbonyl group location influences the rate and extent of interfacial adsorption and the rheology properties of sugar esters at the air-water interface, which were evaluated by dynamic surface tension and complex surface viscoelastic measurements. Octyl glucuronate adsorbs the fastest at the air-water interface whereas glucose octanoate reduces the dynamic surface tension at the lowest value and exhibits the highest film viscoelasticity. Differences are attributed to molecular conformation constraints inducing relevant changes to the surface coverage kinetic capacity and the interaction strengths of the octyl sugar ester adsorbed films at the air-water interface. All of the results are supported by the minimum cross-sectional area values per molecule determined by both experimental and computational approaches. [less ▲]

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See detailFractionation process to produce a new milk ingredient enriched in phospholipids and sphingolipids
Bodson, P.; Dalemans, D.; Danthine, Sabine ULg et al

Poster (2008, October)

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See detailImpact of the spray drying conditions on inulin's physical properties
Ronkart, Sébastien; Blecker, Christophe ULg; Deroanne, Claude et al

Poster (2008, July)

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See detailImpact of physical properties of inulin on stability during moisture sorption.
Ronkart, Sébastien; Paquot, Michel ULg; Fougnies, C. et al

Poster (2008, July)

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See detailA working methodology for the total water determination in inulin by the volumetric Karl Fischer titration.
Ronkart, Sébastien; Blecker, Christophe ULg; Fougnies, C. et al

Poster (2008, July)

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See detailStudy of the stability and the physical property changes of amorphous inulin during moisture adsorption
Ronkart, S.; Paquot, Michel ULg; Fougnies, C. et al

Poster (2008, July)

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See detailEfficiency of sieving or classification for dry fractionation of aot mills and beta-glucans enrichment.
Roiseux, Olivier; Vanderbeke, E.; Blecker, Christophe ULg et al

Poster (2008, June)

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See detailImpact of pre-treatment processing on cereal by-products valorisation through enzymatic extraction of ferulic acid.
Barberousse, Hélène; Roiseux, Olivier; Deroanne, Claude et al

Poster (2008, June)

Detailed reference viewed: 24 (2 ULg)