References of "Blecker, Christophe"
     in
Bookmark and Share    
Peer Reviewed
See detailPhysiological and bio-functional properties of gum arabic: a notable interest for certain human diseases
Eloundou Mballa, Pierre; Goffin, Dorothée ULg; Destain, Jacqueline ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (in press)

Detailed reference viewed: 195 (122 ULg)
Full Text
Peer Reviewed
See detailPhysico-chemical properties and amino acid profiles of sap from Tunisian date palm
Makhouf-Gafsi, Ines; Mokni-Ghribi, Abir; Brahim, Bchir et al

in Scientia Agricola (2016), 73(1), 85-90

Date palm sap (Phoenix dactylifera L.), also known as "legmi", is a fresh juice ex¬tracted from date palm trees. The present study aimed to elucidate the effects of collection time (at the beginning of ... [more ▼]

Date palm sap (Phoenix dactylifera L.), also known as "legmi", is a fresh juice ex¬tracted from date palm trees. The present study aimed to elucidate the effects of collection time (at the beginning of the tapping period and after seven days of collection) on the amino acid profile and physico-chemical properties of date palm sap from both male and female trees. Dry matter, protein, amino acid, and sugar profiles were determined using the Kjeldahl method, High-Performance Liquid Chromatography (HPLC), and High-Performance Anion-Exchange Chro¬matography with Pulsed Amperometric Detection (HPAEC-PAD), respectively. Date palm sap from both male and female trees contained high levels of carbohydrates. HPLC analysis showed that this fraction was dominated by sucrose in the sap sample from female trees compared to that from male trees. Male date palm sap was noted to exhibit lower dry matter content than female date palm sap but higher protein, total polyphenol, ash, and amino acid contents. While the major essential amino acids in the sap from male trees consisted of valine and threonine, they were represented by lysine and phenylalanine in sap samples from female trees. Further, Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) analysis showed the presence of a proteinic band of 30 kDa only for the sap from male trees. Taken together, the sap from both male and female date palm trees had a number of properties that are highly valued by the functional food industry. [less ▲]

Detailed reference viewed: 15 (0 ULg)
Full Text
Peer Reviewed
See detailAirewater interfacial properties of enzymatic wheat gluten hydrolyzates determine their foaming behavior
Wouters, Arno G.B.; Rombouts, Ine; Legein, Marie et al

in Food Hydrocolloids (2016), 55

Insight in the link between foaming and interfacial properties of proteins can increase their potential as functional agents in food systems. Here, foaming capacity and stability of structurally different ... [more ▼]

Insight in the link between foaming and interfacial properties of proteins can increase their potential as functional agents in food systems. Here, foaming capacity and stability of structurally different peptic and tryptic wheat gluten hydrolyzates were related to the kinetics of their adsorption at an airewater interface as well as to the properties of a compressed protein film at this interface. Foams from degree of hydrolysis (DH, i.e. the percentage of cleaved peptide bonds) 2 hydrolyzates were more stable than those from their DH 6 counterparts, and this at all protein concentrations tested. However, at protein concentrations from 0.010% to 0.050% (wprot/v), peptic DH 2 and 6 hydrolyzates had better foaming stability than their tryptic counterparts of the same DH. The opposite was observed when protein concentrations ranged from 0.050% to 0.150% (wprot/v). These observations can in part be explained by the molecular mass composition of the samples and, more importantly, by high levels of hydrophobic peptides in the DH 2 samples. The calculation of an average elasticity (up to 20e25 mN/m) from the variation in surface pressure for a variation in surface area in Langmuir isotherms showed that DH 2 samples had higher elasticity than DH 6 samples, which was in agreement with their foaming stabilities at various protein concentrations. Additionally, although not usually considered in literature, it seemed there was a correspondence between surface pressure at different protein surface concentrations and foaming stability at different protein concentrations. [less ▲]

Detailed reference viewed: 10 (0 ULg)
Full Text
Peer Reviewed
See detailPhysical, functional and structural characterization of the cell wall fractions from baker's yeast Saccharomyces cerevisiae
Borchani, C.; Fonteyn, F.; Jamin, G. et al

in Food Chemistry (2016), 194

The yeast cell wall of Saccharomyces cerevisiae is an important source of β-D-glucan, a glucose homopolymer with many functional, nutritional and human health benefits. In the present study, the yeast ... [more ▼]

The yeast cell wall of Saccharomyces cerevisiae is an important source of β-D-glucan, a glucose homopolymer with many functional, nutritional and human health benefits. In the present study, the yeast cell wall fractionation process involving enzymatic treatments (savinase and lipolase enzymes) affected most of the physical and functional characteristics of extracted fractions. Thus, the fractionation process showed that β-D-glucan fraction F4 had significantly higher swelling power and fat binding capacity compared to other fractions (F1, F2 and F3). It also exhibited a viscosity of 652.12 mPa s and a high degree of brightness of extracted β-D-glucan fraction. Moreover, the fractionation process seemed to have an effect on structural and thermal properties of extracted fractions. Overall, results showed that yeast β-D-glucan had good potential for use as a prebiotic ingredient in food, as well as medicinal and pharmaceutical products. © 2015, Elsevier Ltd. All rights reserved. [less ▲]

Detailed reference viewed: 47 (0 ULg)
Full Text
Peer Reviewed
See detailPhenolic profile, antibacterial and cytotoxic properties of second grade date extract from Tunisian cultivars (Phoenix dactylifera L.)
Kchaou, Wissal; Abbès, Fatma; Ben Mansour, Riadh et al

in Food Chemistry (2016), (194), 1048-1055

The present study aimed to investigate the phenolic profile of second grade date extracts and evaluate their antimicrobial and cytotoxic activities with regard to some pathogenic microorganisms. Phenolic ... [more ▼]

The present study aimed to investigate the phenolic profile of second grade date extracts and evaluate their antimicrobial and cytotoxic activities with regard to some pathogenic microorganisms. Phenolic content was analyzed by HPLC. Antimicrobial activity was evaluated by the agar disk diffusion method, and in vitro cytotoxic activity was examined by cell proliferation assay. The results revealed that second grade dates presented three benzoic acids, five cinnamic acids and two flavonoids, with the predominance of q-coumaric acid (1998.80 lg/100 g). The antimicrobial activities showed that the date extracts were active against Gram (+) and Gram (-) bacteria, showing marked activity against Escherichia coli with an inhibition zone of 25 mm. Cytotoxicity assays showed that the date extracts were able to inhibit the proliferation of HeLa cell lines. The results confirmed that the date extracts were rich in biologically active compounds that are highly valued in the functional food and nutraceutical industries. [less ▲]

Detailed reference viewed: 15 (0 ULg)
Full Text
Peer Reviewed
See detailPHYSICAL-CHEMICAL PROPERTIES OF MILK FAT GLOBULE MEMBRANE AT DIFFERENT STAGES OF ISOLATION
Malik, Priyanka ULg; Danthine, Sabine ULg; Paul, Aman ULg et al

in Scientific Bulletin. Series F. Biotechnologies (2015), XIX

Fat globules in milk are present in form of emulsion stabilized by milk fat globule membrane (MFGM) which originates in mammary gland. Buttermilk which is rich source of MFGM finds application as an ... [more ▼]

Fat globules in milk are present in form of emulsion stabilized by milk fat globule membrane (MFGM) which originates in mammary gland. Buttermilk which is rich source of MFGM finds application as an ingredient in dairy and food industry (emulsions, infant formulas & low fat products) for its emulsifying and stabilizing properties which are associated to polar lipids. Phospholipids & some proteins have also shown some medicinal properties. So, MFGM received much attention in recent years due to its health-beneficial & technological properties. This work has been carried out with the objective to characterize MFGM at different stages of extraction. MFGM fractions were isolated from fresh cream and collected at different steps during processing to study its physical-chemical characterization. The fractions were characterized for their chemical composition to have an idea at which stage which components are isolated. The sample were also characterized for their surface properties which included study of mechanical properties of monolayer using Langmuir film balance, surface tension and zeta potential. Physical-chemical studies of fractions suggest that each fraction of MFGM have different chemical composition and surface properties which could be of interest for use in different food products depending on the requirement. The choice of these fractions could be done for their use as food additive/ingredient in food industry depending on the application. It may even have an extended application in pharmaceutical industry. [less ▲]

Detailed reference viewed: 22 (2 ULg)
Full Text
Peer Reviewed
See detailPhysicochemical properties and thermal behaviour of African wild mango (Irvingia gabonensis) seed fat
Yamoneka, J.; Malumba Kamba, Paul ULg; Blecker, Christophe ULg et al

in LWT - Food Science and Technology (2015), 64

African wild mango (Irvingia gabonensis) is now recognized for its numerous food and medicinal uses. This plant produces seeds rich in fat, which is traditionally used as a soup thickener. In the present ... [more ▼]

African wild mango (Irvingia gabonensis) is now recognized for its numerous food and medicinal uses. This plant produces seeds rich in fat, which is traditionally used as a soup thickener. In the present study, the fat from Irvingia gabonensis seeds was solvent extracted and characterized. Besides a chemical characterization (fatty acid (FA) and triacylglycerol (TG) profiles), the melting and crystallization behaviour of the extracted fat was studied by complementary techniques: pNMR, DSC and X-ray diffraction in order to get basic information regarding its physical properties and more particularly, about its polymorphism. The seeds from Irvingia gabonensis (IG) represent an important source of lipids (69e75 g/100 g), rich in myristic (49.8%) and lauric acid (37%). Due to its FA composition, this fat can be classified among “lauric fats”. The melting profiles of IG fat indicates that a high amount of fat remains solid at temperatures up to 30 °C; the complete melting was detected at around 40 °C. The most stable polymorph of this fat is the ℬ' 1-form. Moreover, IG fat presents a good oxidative stability due to its low content in unsaturated fatty acid. [less ▲]

Detailed reference viewed: 26 (6 ULg)
Full Text
Peer Reviewed
See detailEffect of γ-radiation on free radicals formation, structural changesand functional properties of wheat starch
Atrous, Hager; Benbettaieb, Nasreddine; Hosni, Faouzi et al

in International Journal of Biological Macromolecules (2015), 80

Wheat starch was treated by different γ-radiation doses (3, 5, 10, 20, 35 and 50 kGy). The effects of γ-radiation on structural, thermal, physicochemical, morphological and rheological properties of wheat ... [more ▼]

Wheat starch was treated by different γ-radiation doses (3, 5, 10, 20, 35 and 50 kGy). The effects of γ-radiation on structural, thermal, physicochemical, morphological and rheological properties of wheat starch were studied. The presence of free radicals after γ-radiation treatment, which number decreased with time was confirmed. Structural analysis revealed decreases in the intensities of the O–H and C–H stretches and glycosidic linkages indicating the depolymerization of amylose and probably amy-lopectin into shorter chain molecules, but showed that γ-radiation treatment did not affect the crystalline structure. Differential scanning calorimetric (DSC) thermograms showed the absence of significant differences in the gelatinization temperatures, as well as the corresponding transition enthalpies since the DSC parameters are related to the crystalline ordering within the granules. Apparent amylose content decreased linearly with increasing irradiation dose leading to an increase in water solubility index. Anincrease in the swelling power was observed after irradiation treatment until 20 kGy, followed by a rapiddecrease at higher doses. Microscopic observations showed that the effect of γ-radiation was more visible on starch pastes than on starch granules. Rheological properties of the starch pastes decreased within creasing irradiation dose as a result of glycosidic bond cleavage. [less ▲]

Detailed reference viewed: 29 (0 ULg)
Full Text
Peer Reviewed
See detailEffect of drying methods on physico-chemical and functional properties of chickpea protein concentrates
Ghribi, Abir Mokni; Maklouf Gafsi, Ines; Blecker, Christophe ULg et al

in Journal of Food Engineering (2015), 165

Chickpea protein concentrates (CPCs) were prepared from seed flour by alkaline extraction followed by isoelectric precipitation. The effects of different drying methods (freeze drying and convective ... [more ▼]

Chickpea protein concentrates (CPCs) were prepared from seed flour by alkaline extraction followed by isoelectric precipitation. The effects of different drying methods (freeze drying and convective drying at 40 °C and 50 °C) on physico-chemical and functional properties of CPCs were investigated. CPCs were found to have high contents of protein (61.20–63.12% dry weight basis). Freeze dried concentrate had the highest values of water and oil holding capacities. This drying method gave the lightest CPCs color. The amino acid of CPCs could reach the FAO/WHO requirement (1990) for the essential amino acids for preschool children and the sulfur-containing amino acids were the first limiting amino acids for all three protein concentrates. The solubility-pH profile of different CPCs showed minimum solubility when the pH was between 4.0 and 5.0. All concentrates were able to decrease the interfacial tension. The thermal properties of CPCs were studied by differential scanning calorimetry. CPCs differed significantly (p ≤ 0.05) in peak denaturation temperature and enthalpy of transition. Hence, drying methods used for the preparation of CPCs powders can affect the physico-chemical and functional properties. [less ▲]

Detailed reference viewed: 20 (0 ULg)
Full Text
Peer Reviewed
See detailFoamability and Foam Stability of Male and Female Date Palm Sap (Phoenix dactylifera L.) During the Collection Period
Makhlouf-gafsi, Ines; Mokni-ghribi, Abir; Bchir, Brahim et al

in Food Biophysics (2015)

This work aimed to study the influence of date palm sex on the surface properties of date palm sap (DPS) (Phoenix dactylifera L.) during the collection period. The behavior at the interface and foaming ... [more ▼]

This work aimed to study the influence of date palm sex on the surface properties of date palm sap (DPS) (Phoenix dactylifera L.) during the collection period. The behavior at the interface and foaming properties were evaluated via equilibrium surface tension (drop volume) and bubbling method, respectively. Unlike male sap, the female sap was unable to produce foam due to its low rate of adsorption, low average hydrophobicity values, and low bulk viscosity values throughout the collection period. For male sap, there are significant differences (p<0.05) on foaming properties throughout the collection period. In fact, the last 3 weeks of sap collection were characterized by a decrease pace of surface tension which explains the enhancement of both foam capacity and stability. The last week of collection period present the best foam power (0.9). To explain these differences, the interactions of several factors and their affects on foaming properties were examined. Results showed a positive correlation between foam capacity and average hydrophobicity values. In the other hand, foam stability exhibits a positive correlation with the increase of protein concentration and bulk viscosity. [less ▲]

Detailed reference viewed: 32 (3 ULg)
Full Text
Peer Reviewed
See detailEffects of enzymatic hydrolysis on conformational and functional properties of chickpea protein isolate
Ghribi, Abir Mokni; Maklouf Gafsi, Ines; Sila, Assaâd et al

in Food Chemistry (2015), 187

The impact of enzymatic hydrolysis by Alcalase on the conformational and functional properties of chickpea protein isolate (CPI) was investigated. The physicochemical, interfacial tension and surface ... [more ▼]

The impact of enzymatic hydrolysis by Alcalase on the conformational and functional properties of chickpea protein isolate (CPI) was investigated. The physicochemical, interfacial tension and surface characteristics of CPI and their hydrolysates (CPH) according to the degree of hydrolysis (DH) were also determined. These parameters were then related to the changes in the emulsification activity (EAI) and stability (ESI). The enzymatic hydrolysis was found to improve protein recovery and solubility, leading to a reduction in the molecular weight bands with a concomitant increase in the intensity and appearance of protein bands having apparent molecular mass below 20 kDa. The interfacial tension decreased from _66.5 mN m_1 for CPI to _59.1 mN m_1 for CPH. A similar trend was observed for the surface charge which declined from _27.55 mV to _16.4 mV for the CPI and CPH, respectively. These changes were found to have a detrimental effect on the EAI and ESI values. [less ▲]

Detailed reference viewed: 18 (6 ULg)
Full Text
Peer Reviewed
See detailNutritional and Compositional Study of Desi and Kabuli Chickpea (Cicer Arietinum L.) Flours from Tunisian Cultivars
Ghribi, Abir Mokni; Maklouf, Ines; Blecker, Christophe ULg et al

in Advances in food technology and nutritional sciences (2015), 1(2), 38-47

Two chickpea cultivars (Kabuli, Desi) were analyzed to determine and compare their physical characteristics, chemical composition and functional properties to one another. The main objective is to promote ... [more ▼]

Two chickpea cultivars (Kabuli, Desi) were analyzed to determine and compare their physical characteristics, chemical composition and functional properties to one another. The main objective is to promote their use in food applications and open new opportunities for the development of effective techno-functional additives for use in a wide range of food for¬mulations. Significant differences were revealed among the studied cultivars. Kabuli cultivar has significantly shown (P≤0.05) higher protein content (24.51%), fiber content (21.86%) and lower Water Holding Capacity (WHC) compared to the Desi cultivar. The essential amino ac¬ids were present in chickpea seeds except for tryptophan and cysteine. The sulphur-containing amino acid was the first limiting amino acid. The protein solubility-pH profile of chickpea powders revealed a minimum solubility in the pH between 4 and 5 ranging from 14% to 20% for Kabuli cultivar and 17% to 30% for Desi cultivar. Foaming capacity from different chickpea was observed in the range of 36.9-41% and found significantly different (P≥0.05). Emulsify¬ing Activity (EA) decreased with the increase of flours concentration. Maximum EA (~20%) were observed for Kabuli cultivar. Gelation properties improved when flour concentration in¬creased and the Least Gelation Concentration (LGC) was about 14% for Kabuli cultivar and 16% for Desi cultivar. Chickpea gels were evaluated for their instrumental textural properties. High-quality chickpea flour with improved nutritional properties and good functional proper¬ties could beneficially be used in the formulation of food, such as meat, dairy and bakery prod¬ucts. [less ▲]

Detailed reference viewed: 14 (0 ULg)
Full Text
See detailL'évolution de la conception des aliments : de l'empirisme à la formulation raisonnée
Blecker, Christophe ULg

Scientific conference (2015, March 19)

Detailed reference viewed: 35 (5 ULg)
Full Text
See detailEtude des propriétés moussantes de la sève du palmier dattiers (Phoenix Dactylifera L.)
Makhlouf, Ines; Razafindralambo, Hary; Attia, Hamadi et al

Conference (2015, March 17)

Detailed reference viewed: 24 (1 ULg)
Full Text
See detailL'innovation dans la filière céréalière: agir à différents étages
Roiseux, Olivier; Vanderbeke, Erik; Blecker, Christophe ULg

Scientific conference (2015, March 16)

Detailed reference viewed: 29 (4 ULg)
Full Text
See detailEffets de l'hydrolyse enzymatique sur propriétés fonctionnelles et conformationnelles des isolats proteiques de pois chiches
Mokni Ghribi, Abir; Maklouf Gafsi, Ines; Sila, Assaad et al

Conference (2015, March 16)

Detailed reference viewed: 20 (1 ULg)
Full Text
See detailFood Compounds from Meadow Grasshoppers
Paul, Aman ULg; Frederich, Michel ULg; Uyttenbroeck, Roel ULg et al

Poster (2015, March 15)

Eating insects as food, particularly grasshopper is practiced in many cultures throughout the world. Meadow grasshopper (Chorthippus parallelus) is commonly found in Europe and some part of Asia. It is ... [more ▼]

Eating insects as food, particularly grasshopper is practiced in many cultures throughout the world. Meadow grasshopper (Chorthippus parallelus) is commonly found in Europe and some part of Asia. It is already known that grasshoppers of Chorthippus species are consumed as food in countries such as Thailand. With the aim of evaluating the nutritional potential of this insect species the proximate nutritional composition of grasshoppers caught from the local fields was realized. Besides this, the fatty acid profile of extracted lipids, amino acid profile and mineral composition of the insect was also revealed. Results suggest that meadow grasshopper is an excellent source of protein and essential amino acids. Lipids extracted from the grasshopper have an interesting fatty acid composition. Also the grasshopper contains some minerals that are important for body. With such protein content, amino acid profile, fatty acid profile of the lipids and mineral content this grasshopper species could present an interesting alternate to conventional protein sources. [less ▲]

Detailed reference viewed: 69 (21 ULg)
Full Text
See detailDéveloppement d'un modèle mathématique d'identification des différents tissus externes de son de blé dur et tendre (Triticum durum et Triticum aestivum) basé sur l'étude histologique macroscopique et microscopique et la composition biochimique des fractions
Ben Amouda, Mohamed Salah; Roiseux, Olivier; Olive, Gilles et al

Poster (2015, March 15)

Le blé est constitué de trois régions : l’albumen, les enveloppes et le germe. Le blé sert depuis longtemps de nourriture de base à l’homme pour donner, après mouture, à la farine dans le cas des blés ... [more ▼]

Le blé est constitué de trois régions : l’albumen, les enveloppes et le germe. Le blé sert depuis longtemps de nourriture de base à l’homme pour donner, après mouture, à la farine dans le cas des blés tendres, ou à la semoule dans le cas des blés durs. Le produit obtenu correspond à la majorité de l’albumen. Le son de blé est quant à lui un coproduit de cette transformation. C’est un empilement de différents tissus : péricarpe externe et interne, testa, épiderme et aleurone. Actuellement, la valorisation du son de blé reste faible malgré son potentiel nutritionnel. Or ce potentiel permettrait un développement d’additifs alimentaires à haute valeur ajoutée si un fractionnement correct suivi d’une analyse histochimique complète des factions obtenues pouvait être réalisés. Parmi les méthodes de fractionnement, note choix s’est porté sur le debranning qui se base sur le retrait séquentiel des différentes couches extérieures du blé (voir la communication « Mise au point du fractionnement par debranning des tissus périphériques du blé tendre (Triticum aestivum) et du blé dur (Triticum durum) ». Afin de quantifier l’efficacité du fractionnement, l’investigation de la répartition des tissus au sein des fractions produites a été réalisée par l’étude macroscopique (visuelle) et microscopique (coloration histologique spécifique) des grains et des fractions. Un modèle mathématique qui permet l’appréciation de la distribution des couches dans les différentes fractions a également été développé sur base des bio-marqueurs et de la composition biochimique des fractions. L’étude visuelle macroscopique montre que les grains dans tous les cas attaqués de façon hétérogène et ce en raison de la géométrie particulière des grains de blé. L’étude histologique microscopique montre que, malgré cela, certaines fractions sont enrichies en tissus particuliers. Donc, quelque soit la variété étudiée, les fractions obtenues par debranning présenteront toujours une hétérogénéité de composition tissulaire. Après étude du profil nutritionnel (analyse composition chimique), la variété Karim semble la plus intéressante, car elle est riche en protéines, lipides et minéraux. Au niveau des fractions, pour toutes les variétés, la fraction F1 présente le meilleur potentiel. [less ▲]

Detailed reference viewed: 33 (7 ULg)
Full Text
See detailPhysicochemical properties and thermal behaviour of African wild mango (Irvingia gabonensis) seed oil.
Yamoneka, Juste; Malumba Kamba, Paul ULg; Blecker, Christophe ULg et al

Poster (2015, March 15)

African wild mango (lrvingia gabonensis) is now recognized for its numerous food and medicinal uses. This plant produces seeds rich in fat, which is traditionally used as a soup thickener. in the present ... [more ▼]

African wild mango (lrvingia gabonensis) is now recognized for its numerous food and medicinal uses. This plant produces seeds rich in fat, which is traditionally used as a soup thickener. in the present study, the proximate composition of seeds from lrvingia gabonensis is reported. The oil from the seeds was then solvent extracted; its fatty acid (FA) and triacylglycerol (TG) profiles were determined. Besides this chemical characterization, the melting and crystallization behaviour of the extracted fat was studied by pNMR, DSC and X-ray diffraction. The result of this investigation showed that the seeds from lrvingia gabonensis (IG) represent an important source of lipids (69-75%), rich in myristic (49.8%) and lauric acid (37%). This fat can be classified among "lauric fats". IG oil presents a good oxidative stability due to its low content in unsaturated fatty acid. The melting profiles of IG oil indicates that a high amount of fat remains solid at temperatures up to 30°C; the complete melting was detected at around 40C. The most stable polymorph of this fat is the β'1 -form. [less ▲]

Detailed reference viewed: 44 (9 ULg)