References of "Blecker, Christophe"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailThermal and structural behaviour of four industrial laurie fats
Anihouvi, Prudent; Blecker, Christophe ULg; Dombrée, Anne et al

Poster (2013)

Detailed reference viewed: 7 (5 ULg)
Full Text
Peer Reviewed
See detailComparison of the physicochemical behavior of model oil-in-water emulsions based on different lauric vegetal fats
Anihouvi, Prudent; Danthine, Sabine ULg; Kegelaers, Yves et al

in Food Research International (2013), 53

Detailed reference viewed: 4 (1 ULg)
Full Text
Peer Reviewed
See detailEffect of New Synthetic PEGylated Ferulic Acids in Comparison to Ferulic Acid and Commercial Surfactants on the Properties of Wheat Flour Dough and Bread
Nicks, Francois ULg; Richel, Aurore ULg; Dubrowski, Thomas ULg et al

in Journal of the Science of Food and Agriculture (2013), 93(10), 2415-2420

BACKGROUND: Ferulic acid esterified with poly(ethylene glycol) with three different average molecular weights (200, 400 and 1000 g/mol) was studied in breadmaking. The effects of these antioxidants on the ... [more ▼]

BACKGROUND: Ferulic acid esterified with poly(ethylene glycol) with three different average molecular weights (200, 400 and 1000 g/mol) was studied in breadmaking. The effects of these antioxidants on the properties of wheat flour dough and bread were analyzed and compared with those obtained with ferulic acid and two commercial surfactants, diacetyl tartaric acid ester of mono- and diglycerides and sodium stearoyl lactylate. Farinographic and alveographic methods as well as weight, volume and bread firmness measurements were used for this purpose. <br /> <br />RESULTS: Such as ferulic acid, when the PEGylated derivatives were implemented in the dough (5000 ppm), it accelerated its breakdown and decreased its rheological properties. However, it allowed to avoid the important diminution of loaf volume observed when dough supplemented with ferulic acid was baked. That decrease in volume was related to the inhibition of the yeast (Saccharomyces cerevisae) by the unesterified ferulic acid. Moreover, two of the PEGylated ferulic acids even contributed to an increase of loaf volumes (5-6%) and demonstrated crumb softener properties. <br /> <br />CONCLUSION: The addition of ferulic acid in wheat flour dough caused the inhibition of the yeast, which resulted in decreased bread volume. That effect could be avoid by the esterification of ferulic acid with poly(ethylene glycol). [less ▲]

Detailed reference viewed: 54 (25 ULg)
Full Text
Peer Reviewed
See detailEnzymatic synthesis and surface properties of novel rhamnolipids
Nott, Katherine ULg; Richard, Gaetan ULg; Laurent, Pascal ULg et al

in Process Biochemistry (2013), 48

New rhamnolipids were obtained via the development of a synthesis procedure consisting of two biocatalyzed steps. In the first step, naringinase was used to introduce a primary alcohol function onto ... [more ▼]

New rhamnolipids were obtained via the development of a synthesis procedure consisting of two biocatalyzed steps. In the first step, naringinase was used to introduce a primary alcohol function onto rhamnose by glycosylation of 1,3-propanediol. In the second step, immobilized lipase B from Candida antarctica catalyzed the esterification of the primary hydroxyl group with mono- and di-carboxylic fatty acids of increasing chain length (from C8 to C14). For the monoic acids, the initial rate and 24 h yield decreased with increasing chain length. For the dioic acid, the number of carbon atoms of the acid did not influence these parameters. The new rhamnolipid obtained with tetradecanoic acid showed very good surface properties. At pH 5, it had a very low critical aggregation concentration of 1.70 M and it diminished water’s surface tension to 27.6 mN/m. It was also able to form stable insoluble monolayers. On the other hand, the rhamnolipid formed with tetradecanedioic acid showed far less interesting surface properties. [less ▲]

Detailed reference viewed: 30 (11 ULg)
Full Text
Peer Reviewed
See detailEffects of extraction solvents on phenolic contents and antioxidant activities of Tunisian date varieties (Phoenix dactylifera L.)
Kchaou, W; Abbès, F; Blecker, Christophe ULg et al

in Industrial Crops & Products (2013), 45

Second-grade dates (Phoenix dactylifera L.), with hard texture, from six Tunisian cultivars were analysed for their composition and antioxidant activities. Results showed predominance of total sugars and ... [more ▼]

Second-grade dates (Phoenix dactylifera L.), with hard texture, from six Tunisian cultivars were analysed for their composition and antioxidant activities. Results showed predominance of total sugars and a relatively low content of protein, fat andash. On the other hand, optimisation of extraction of antioxidant was carried using five different solvents. The highest level of phenolic compounds for all dates varieties was found in the 70% acetone extract. This level ranged from 199.43 to 576.48 mg of GAE/100 g fresh weight. However, extraction into 50% methanol gave the highest antioxidant activity from 89.55 to 109.67 mg equivalents of ascorbic acid/g fresh weight. For both two olvents, Bejo exhibited the highest phenolic content and total antioxidant activity, while Baydh El Hamam presented the owest. A positive linear correlation between total antioxidant activity and phenolic contents was observed (R2 = 0.83; R2 = 74 for acetone/H2O and methanol/H2O, respectively). The antioxidant activity of acetone/H2O and methanol/H2O extracts was carried using DPPH radical-scavenging activity and reducing power. These results showed that dates had strongly scavenging activity on DPPH reaching 90.12% in methanol/H2O from Deglet Nour. Whereas, acetone/H2O showed the best reducing power which Bejo was significantly higher than the other varieties. This study demonstrates the potential antioxidant activity with Tunisian date, that we can use these natural extracts as food additives in replacement of synthetic compounds. [less ▲]

Detailed reference viewed: 37 (2 ULg)
Full Text
Peer Reviewed
See detailEffect of extraction conditions on the yied and purity of ulvan extracted from Ulva lactuca
Yaich, Hela; Garna, Haikel; Besbes, Souhail et al

in Food Hydrocolloids (2013)

A study of the influence of extraction conditions (pH: 1.5 and 2; temperature: 80 °C and 90 °C; extraction time: 1-3 h), on the yield, chemical composition and purity of the sulphated cell wall ... [more ▼]

A study of the influence of extraction conditions (pH: 1.5 and 2; temperature: 80 °C and 90 °C; extraction time: 1-3 h), on the yield, chemical composition and purity of the sulphated cell wall polysaccharides ulvan, extracted from the green seaweed Ulva lactuca and precipitated by alcohol is carried out. The alcohol precipitate yields varied from 21.68% to 32.67% (%dw/dw) depending on the pH. At pH 2, the alcohol precipitate yields and the uronic acid recovery from extract juice are higher than those obtained at pH 1.5. Other compounds than ulvan such as cellulose, hemicellulose, proteins and ash are solubilized from the cell walls of Ulva lactuca at both pH, and they are precipitated with alcohol. The alcohol precipitate obtained from different extraction conditions has high uronic acid (20.37%-23.60%) and neutral sugar content (20.09%-29.12%), especially when the conditions (pH, temperature) are drastic. It contains rhamnose (13.35%-15.59%), glucose (2.90%-10.97%), and xylose (2.36%-2.73%). A decrease in the molecular weight of ulvan was observed at acid pH, and for long extraction times. The presence of proteins (1.94%-2.32%) and inorganic material (33.36%-47.15%) in alcohol precipitate prove the lower purity of ulvan extracted and shows that ulvan precipitation with ethanol is not specific. © 2012 Elsevier Ltd. [less ▲]

Detailed reference viewed: 86 (5 ULg)
Full Text
Peer Reviewed
See detailInfluence of processing parameters on physicochemical properties of low-trans and trans-free puff pastry margarines
Lefebure, Emilie ULg; Ronkart, Sébastien; Brostaux, Yves ULg et al

in LWT - Food Science and Technology (2013), 51(1), 225-232

Detailed reference viewed: 39 (22 ULg)
Full Text
Peer Reviewed
See detailInfluence of monopalmitin on the isothermal crystallization mechanism of palm oil
Verstringe, S.; Danthine, Sabine ULg; Blecker, Christophe ULg et al

in Food Research International (2013), 51(1), 344-353

Detailed reference viewed: 18 (0 ULg)
Full Text
Peer Reviewed
See detailCharacterization of sugar beet pectic-derived oligosaccharides obtained by enzymatic hydrolysis.
Combo, Agnan Marie Michel ULg; Aguedo, Mario ULg; Quiévy, N et al

in International Journal of Biological Macromolecules (2013), 52(1), 148-156

Detailed reference viewed: 76 (28 ULg)
Full Text
Peer Reviewed
See detailInfluence of steam explosion on physico-chemical properties and hydrolysis rate of pure cellulose fibers
Jacquet, Nicolas ULg; Vanderghem, Caroline ULg; Danthine, Sabine ULg et al

in Bioresource Technology (2012), 121(221-227),

The aim of the present study is to compare the effect of different steam explosion treatments on physicochemical properties and hydrolysis rate of a pure bleached cellulose. The results showed that ... [more ▼]

The aim of the present study is to compare the effect of different steam explosion treatments on physicochemical properties and hydrolysis rate of a pure bleached cellulose. The results showed that moderate steam explosion treatments (severity factor below 5.2) did not improve the enzymatic hydrolysis rate of the cellulose fibers. The characterization of the obtained samples showed an increase of the cellulose accessibility coupled with an increase of the overall crystallinity of the substrate. In these conditions, the higher accessibility is counterbalanced by the increased crystallinity. Indeed, a greater proportion of the substrat is accessible by only a fraction of the enzymatic complex (exo-glucanases) activities. When the severity factor reached 5.2, a decrease of the cellulose enzymatic hydrolysis rate was observed. In this case, TGA analysis showed an increase of the char level at the end of the pyrolysis which traduced an important thermal degradation of the samples. The thermal degradation of cellulose lead to an important change in substrate composition, which induced a decrease of the cellulose ratio available for hydrolysis and caused a decrease of the hydrolysis yields. [less ▲]

Detailed reference viewed: 68 (20 ULg)
Full Text
Peer Reviewed
See detailImprovement of the cellulose hydrolysis yields and hydrolysate concentration by management of enzymes and substrate input
Jacquet, Nicolas ULg; Vanderghem, Caroline ULg; Blecker, Christophe ULg et al

in Cerevisia : Belgian Journal of Brewing and Biotechnology (2012), 37

In order to improve the hydrolysis of cellulose fiber and to obtain highly concentrated hydrolysate, two methods based on successive addition of enzyme and substrate were assessed. The first method, which ... [more ▼]

In order to improve the hydrolysis of cellulose fiber and to obtain highly concentrated hydrolysate, two methods based on successive addition of enzyme and substrate were assessed. The first method, which required only substrate addition, allowed to increase by 50% the hydrolysate concentration and to decrease by 30% enzyme units needed. The second method highlighted the ability to reach very high concentrated hydrolysate (up to 170 g/l) by simultaneous addition of enzyme and substrate. In parallel, relationships between some limiting factors and the yields of hydrolysis were investigated. In conclusion, viscosity evolution of cellulose suspension during hydrolysis step was investigated with an aim to improve the management of enzyme and substrate addition. [less ▲]

Detailed reference viewed: 40 (17 ULg)
Full Text
See detailAn emulsion whippable at room-temperature
Dombrée, Anne; Kegelaers, Yves; Anihouvi, Prudent Placide et al

Patent (2012)

he present invention relates to an oil-in-water emulsion for whipped cream and to a whipped cream obtained by whipping the emulsion. In particular, the present invention relates to a stabilized whippable ... [more ▼]

he present invention relates to an oil-in-water emulsion for whipped cream and to a whipped cream obtained by whipping the emulsion. In particular, the present invention relates to a stabilized whippable oil-in-water emulsion upon increasing the trilaurin triglyceride content of its oily phase, and to the stabilized cream obtained by whipping the emulsion. The present invention further relates to the methods for obtaining this emulsion and this cream, and to the uses of an oil-in-water emulsion according to the invention or of the stabilized cream according to the invention. [less ▲]

Detailed reference viewed: 80 (24 ULg)
Peer Reviewed
See detailFeeding humans with edible insects : actual state and perspectives in Belgium and Europe
Sablon, Ludovic ULg; Alabi, Taofic; Drugmand, Didier et al

Poster (2012, August)

In future decades, world population will grow up to 9 billion of people and we will be confronted to a lack of nutritive resources. We will not continue to produce proteins with our conventional livestock ... [more ▼]

In future decades, world population will grow up to 9 billion of people and we will be confronted to a lack of nutritive resources. We will not continue to produce proteins with our conventional livestock as beef, poultry or pig. It will therefore look to other sources and edible insects are one of these solutions. Indeed, more than 2000 species of edible insects were actually consumed by 3000 ethnic groups in the world. In undernourished populations, entomophagy is essential to relieve deficiencies in proteins, fatty acids and some vitamins. In Europe, we have acquired sedentary habits and we have lost our ancestral harvesting and hunting traditions. It is the reason of disinterest for edible insects and entomophagy was considered as a "barbarian" food habit. Facing food challenges of tomorrow, it is important to sensitize industrialized populations and to reintroduce edible insects in our plates and habits. The first step is to overcome neophobia of food products. Our studies focused on different insect preparations and on perception of entomophagy by different age classes. Globally, our first results indicated that entomophagy was accepted by belgian consumers but the more difficult for them is to taste the first time. These results confirmed neophobia for this type of food products and thus the importance of positive informations and education for acceptance of entomophagy. [less ▲]

Detailed reference viewed: 374 (71 ULg)
Full Text
Peer Reviewed
See detailEffect of heat treatment of rennet skim milk induced coagulation on the rheological properties and molecular structure determined by synchronous fluorescence spectroscopy and turbiscan
Blecker, Christophe ULg; Habib-Jiwan, Jean-Michel; Karoui, Ramdhane

in Food Chemistry (2012), 135(3), 1809-1817

Heat treatment applied to milk induces denaturation of whey proteins, leading to a complex mixture of whey protein and whey protein coated casein micelles. The present paper investigates the effects of ... [more ▼]

Heat treatment applied to milk induces denaturation of whey proteins, leading to a complex mixture of whey protein and whey protein coated casein micelles. The present paper investigates the effects of heat treatment (60 and 80 °C during 20 min) and rennet-induced coagulation temperature (30 and 40 °C) determined by rheology, synchronous fluorescence spectroscopy (SFS) and turbiscan measurements. The gelation times determined by rheology and SFS increased with the increase of heat treatment applied to milk. The rise in temperature induced a decrease in the maximum curd firming rate and an increase in the viscosity of the investigated milk samples. The principal component analysis (PCA) applied, sepa- rately, to the SF and turbiscan spectra showed a clear discrimination between: (i) raw milks and heated milks; and (ii) milks renneted at 30 °C from those renneted at 40 °C. The results showed the ability of SFS as a rapid and non-destructive technique for the: (i) monitoring network structure and molecular inter- action during the coagulation process; and (ii) determination of gelation time of rennet-induced coagu- lation of studied milk samples. [less ▲]

Detailed reference viewed: 8 (0 ULg)
Peer Reviewed
See detailSe nourrir demain : L'entomophagie, une solution ?
Sablon, Ludovic ULg; Alabi, Taofic; Drugmand, Didier et al

Conference (2012, June 01)

La consommation d'insectes, l'entomophagie, est pratiquée dans de nombreux pays du Monde : plus de 1400 espèces d'insectes sont consommées quotidiennement par environ 3500 groupes ethniques. Si toutefois ... [more ▼]

La consommation d'insectes, l'entomophagie, est pratiquée dans de nombreux pays du Monde : plus de 1400 espèces d'insectes sont consommées quotidiennement par environ 3500 groupes ethniques. Si toutefois l'entomophagie reste peu connue et rare dans nos pays industrialisés, en raison de la très bonne valeur nutritionnelle des insectes, force est de reconnaître son intérêt et son utilité pour les populations sous-alimentées ou n'ayant pas d'accès réguliers à des sources de protéines animales (mammifères, poissons et/ou oiseaux). L'analyse de la composition chimique de diverses espèces d'insectes révèle la présence de teneurs élevées en protéines, lipides, vitamines et minéraux nécessaires aux besoins alimentaires et énergétiques quotidiens de l'être humain. De plus, avec des taux de conversion de la biomasse végétale supérieure à nos élevages traditionnels de bovins, porcins, ovins et volailles, les insectes apparaissent comme une alternative durable pour la production de protéines animales. Toutefois, nos études révèlent, qu’en dépit de leur valeur nutritionnelle et un système de production moins polluant, les Occidentaux manifestent une phobie alimentaire culturelle envers les insectes. Une éducation alimentaire et des suppléments d'informations sur les insectes comestibles apparaissent donc nécessaires pour faire de l'entomophagie une solution alimentaire concrète dans un contexte de production et de consommation durables mais aussi rentables pour les futures décennies. [less ▲]

Detailed reference viewed: 625 (83 ULg)
See detailDesign of sugar-based surface active agents for emulsion polymerization in supercritical carbon dioxide
Boyère, Cédric ULg; Favrelle, Audrey; Broze, Guy ULg et al

Conference (2012, May 10)

The use of aqueous dispersed media, such as emulsions, has many advantages over solution processes for chemical transformations and polymerization reactions, i.e. limited environmental impact, ease of ... [more ▼]

The use of aqueous dispersed media, such as emulsions, has many advantages over solution processes for chemical transformations and polymerization reactions, i.e. limited environmental impact, ease of products recovery and increased reaction rate. Emulsions are usually implemented from a water/organic solvent mixture in the presence of a surfactant. However, supercritical carbon dioxide (scCO2) (Pc =74 bars; Tc = 31°C) constitutes an interesting alternative to the traditional organic solvents in these heterogeneous systems because it is inexpensive, non-toxic, non-inflammable and environmentally friendlier. In this context, we developed a novel class of surfactants for the stabilization of H2O/scCO2 emulsions, i.e. fluorinated modified carbohydrates. The hydrophilic head of the surfactant consists in a sugar moiety whereas a fluorinated tail is specifically located in the scCO2 phase. The strategies for the synthesis of these carbohydrates esters rely on selective lipase-catalyzed modifications of sugars and on the versatile thiol-Michael addition reaction. The ability of these molecules to decrease the H2O/scCO2 interfacial tension and to stabilize such emulsions will be presented. Finally, high internal phase scCO2-in-water emulsion (HIPE) were prepared with these new surfactants and used as template for the acrylamide polymerization. The monomer is polymerized in the continuous aqueous phase before removing the CO2 droplets (at least 70 % of the total volume). The resulting permeable porous polymers, called polyHIPEs, exhibit highly interconnected voids (cfr SEM picture) and should be valuable in many applications including support for catalyst, filtration process, immobilization of proteins, etc. [less ▲]

Detailed reference viewed: 35 (17 ULg)
Full Text
Peer Reviewed
See detailA sustainable method inspired by nature for the production of original bi-functional nutraceuticals containing prebiotic fibers and highly bio-available forms of calcium and magnesium
Goffin, Dorothée ULg; Blecker, Christophe ULg; Paquot, Michel ULg

Poster (2012, April 18)

A sustainable method inspired by nature is proposed leading to an original bifunctional product active on gut health, metabolism regulation, immunity and mineral fortification, fighting against topical ... [more ▼]

A sustainable method inspired by nature is proposed leading to an original bifunctional product active on gut health, metabolism regulation, immunity and mineral fortification, fighting against topical chronic diseases (type2 diabetes, osteoporosis, colon cancer…). [less ▲]

Detailed reference viewed: 13 (1 ULg)