References of "Blecker, Christophe"
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See detailInterfacial activities of milk total proteose-peptone: contribution 1 and miscibility of 2 nonhydrophobic and hydrophobic fractions
Karamoko, Gaoussou; Renaville, Robert ULg; Blecker, Christophe ULg

in International Dairy Journal (in press)

Surface properties of a nonhydrophobic fraction of proteose-peptone (NHFPP) and a hydrophobic fraction of proteose-peptone (HFPP), obtained by hydrophobic-interaction chromatography, were investigated ... [more ▼]

Surface properties of a nonhydrophobic fraction of proteose-peptone (NHFPP) and a hydrophobic fraction of proteose-peptone (HFPP), obtained by hydrophobic-interaction chromatography, were investigated. Adsorption of NHFPP and HFPP on the surface activity of total proteose-peptone (TPP) followed a competitive mechanism, especially during the penetration phase and molecular rearrangements. Compression of mixed monolayers was used to study the miscibility of NHFPP and HFPP within TPP films. When NHFPP was mixed with HFPP, in a TPP film, both fractions were immiscible at the beginning of adsorption; they only became miscible when the polypeptide chains had moved from the surface to the aqueous phase, thus allowing a better organisation of proteins. The equation of excess free energy of compression was used to determine the interactions of NHFPP-HFPP within the TPP film through the mixed monolayer (thermodynamic properties); interactions between NHFPP and HFPP appeared less important than those that occurred between molecules within each fraction. [less ▲]

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See detailIn situ analysis of lipid oxidation in oilseedbased food products using near-infrared spectroscopy and chemometrics: The sunflower kernel paste (tahini) example
Mureșan; Danthine, Sabine ULg; Mureșan, Andruța Elena et al

in Talanta (in press)

A new near-infrared (NIR) spectroscopic method was developed for the analytical measurement of lipid oxidation in sunflower kernel paste (tahini), which was chosen as an example of a complex oilseed-based ... [more ▼]

A new near-infrared (NIR) spectroscopic method was developed for the analytical measurement of lipid oxidation in sunflower kernel paste (tahini), which was chosen as an example of a complex oilseed-based food product. The NIR spectra of sunflower tahini were acquired for the extracted fat phase (EFP) and for the intact sunflower tahini (IST) samples during controlled storage. The best peroxide value (PV) calibration models were considered suitable for quality control (ratio of performance of deviation [RPD] >5). The best PV partial least squares (PLS) model result for EFP (RPD 6.36) was obtained when using standard normal variate (SNV) and the Savitzky-Golay first derivative in the 1140-1184 nm, 1388-1440 nm and 2026-2194 nm regions. In the case of IST spectra, the best PV models (RPD 5.23) were obtained when either multiple scattering correction (MSC) or SNV were followed by the Savitzky-Golay second derivative for the 1148-1180 nm and 2064-2132 nm regions. There were poor correlations between the NIR-predicted values and the reference data of the panisidine value (pAV) for both EFP and IST. Overall, the results obtained showed that NIR spectroscopy is an appropriate analytical tool for monitoring sunflower paste PV in situ. Due to the nonexistence of the extraction step, it demonstrates a unique and substantial advantage over presently known methods. Based on these results it is strongly recommended that, when using NIR PLS models to assess lipid oxidation in situ in similar oilseedbased food products (e.g., sesame tahini, hazelnut and cocoa liquor used for chocolate production, peanut butter, hazelnut, almond, pistachio spreads), suitable calibration sets containing samples of different particle sizes and stored at different temperatures be selected. [less ▲]

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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)

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See detailGamma radiation induced modifications of tapioca starch
Atrous, Hager; Benbettaïeb, Nasreddine; Hosni, Faouzi et al

in Asian Academic Research Journal of Multidisciplinary (2016), 3(3), 187-220

The effect of gamma radiation (3, 5, 10, 20, 35 and 50 kGy) on the morphological, structural, physicochemical, pasting and thermal properties of tapioca starch was studied. Microphotographs of scanning ... [more ▼]

The effect of gamma radiation (3, 5, 10, 20, 35 and 50 kGy) on the morphological, structural, physicochemical, pasting and thermal properties of tapioca starch was studied. Microphotographs of scanning electron microscopy and polarized light microscopy revealed the absence of morphological changes induced by gamma radiation. The X-ray diffraction spectra showed that irradiation treatment did not influence the shape and intensity of X-ray diffraction peaks. The presence of free radicals in the irradiated tapioca starch was confirmed by electron spin resonance spectrometry. Fourier transform infrared spectroscopy showed that the irradiated starch displayed a significant decrease in the intensity of the O–H and C–H stretches, bending modes of water and glycosidic linkages. Irradiation improved the water solubility index of starch granules and depressed the apparent amylose content. An increase in the swelling power was observed after irradiation treatment until 20 kGy, followed by a decrease at higher doses. Brabender viscoamylograph test showed that the maximal consistency of the starch paste decreased significantly with increasing irradiation dose. There was no significant difference in the gelatinization temperatures, as well as the corresponding transition enthalpies among native and irradiated tapioca starch samples, as shown in the differential scanning calorimetry thermograms. [less ▲]

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See detailEffect of ultrafiltration process on physico-chemical, rheological, microstructure and thermal properties of syrups from male and female date palm saps
Makhlouf-Gafsi, Ines; Baklouti, Samia; Mokni, Abir et al

in Food Chemistry (2016), 203

This study investigates the effect of the ultrafiltration process on physicochemical, rheological, microstructure and thermal properties of syrups from male and female date palm sap. All the studied ... [more ▼]

This study investigates the effect of the ultrafiltration process on physicochemical, rheological, microstructure and thermal properties of syrups from male and female date palm sap. All the studied syrups switched from pseudoplastic rheological behaviour (n = 0.783) to Newtonian behaviour (n〰1) from 10 to 50 s‾1 respectively and present similar thermal profiles. Results revealed that the ultrafiltration process significantly affects the rheological behaviour of the male and female syrups. These differences on rheological properties are attributed to the variation of chemical composition between sap and sap permeate syrups. Furthermore, the effect of temperature on viscosity of the syrups was investigated during heating and cooling processes at the same shear rate (50 s 1). This study provides idea of the stability of the syrup by evaluating the area between heating and cooling curves. Actually, the syrup prepared from male sap permeate is the most stable between the four studied syrups. [less ▲]

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See detailAssessment of partial coalescence in whippable oil-in-water food emulsions
Petrut, Raul Flaviu ULg; Danthine, Sabine ULg; Blecker, Christophe ULg

in Advances in Colloid and Interface Science (2016), (229), 25-33

Partial coalescence influences to a great extent the properties of final food products such as ice cream and whipped toppings. In return, the partial coalescence occurrence and development are conditioned ... [more ▼]

Partial coalescence influences to a great extent the properties of final food products such as ice cream and whipped toppings. In return, the partial coalescence occurrence and development are conditioned, in such systems, by the emulsion's intrinsic properties (e.g. solid fat content, fat crystal shape and size), formulation (e.g. protein content, surfactants presence) and extrinsic factors (e.g. cooling rate, shearing). A set of methods is available for partial coalescence investigation and quantification. These methods are critically reviewed in this paper, balancing the weaknesses of themethods in terms of structure alteration (for turbidity, dye dilution, etc.) and assumptions made for mathematical models (for particle size determination) with their advantages (good repeatability, high sensitivity, etc.).With the methods proposed in literature, the partial coalescence investigations can be conducted quantitatively and/or qualitatively. Good correlation were observed between some of the quantitative methods such as dye dilution, calorimetry, fat particle size;while a poor correlation was found in the case of solvent extraction method with other quantitativemethods. The most suitableway for partial coalescence quantification was implied to be the fat particle size method, which would give results with a high degree of confidence if used in combination with a microscopic technique for the confirmation of partial coalescence as the main destabilization mechanism. [less ▲]

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See detailTemperature and moisture storage in crop-based materials: Modelling a straw bale wall subject to a thermal shock
Dubois, Samuel ULg; Evrard, Arnaud ULg; Blecker, Christophe ULg et al

in Jounal of Building Physics (2016)

Modelling the hygrothermal behaviour of crop-based insulation products is essential to assess their impact on the energy performance of the building, predict indoor climate conditions, and prevent any ... [more ▼]

Modelling the hygrothermal behaviour of crop-based insulation products is essential to assess their impact on the energy performance of the building, predict indoor climate conditions, and prevent any risk of unexpected degradation. Traditionally, transient numerical models that predict internal conditions of construction materials consider that the variation of moisture storage with temperature is negligible although the sorp- tion behaviour is known to be temperature dependent. This paper investigates this par- ticular effect for crop-based materials and uses a refinement of standard mathematical representations. For this purpose, the effects of a thermal shock on the evolution of hygrothermal conditions inside a straw-bale wall are studied with several versions of a flexible research model. The latter is capable of incorporating the temperature depen- dency of the sorption curve with both a physically-based and an empirical description. A large climate chamber is used to gather experimental data and is able to host a full- size straw bale prefabricated panel. Internal conditions of straw bales are obtained with proper sensors bars. Results show that when large temperature gradients occur in a crop-based material, a model that considers temperature effect on moisture storage enhances greatly the prediction of internal conditions. [less ▲]

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See detailOptimization of a cheap and residential small-scale production of edible crickets with local by-products as an alternative protein-rich human food source in Ratanakiri Province (Cambodia)
Caparros Megido, Rudy ULg; Alabi, Taofic ULg; Nieus, Clément et al

in Journal of the Science of Food and Agriculture (2016)

Background - Health status of the indigenous people of the Ratanakiri Province, Cambodia, is significantly lower compared to the rest of the nation. The domestication and mass production of insects may ... [more ▼]

Background - Health status of the indigenous people of the Ratanakiri Province, Cambodia, is significantly lower compared to the rest of the nation. The domestication and mass production of insects may represent a sustainable, cost effective and high quality alternative source of protein to traditional livestock. This study aimed to optimise a cheap and residential cricket breeding system based on unused wild resources. The cricket development, Teleogryllus testaceus (Walker), under seven diets composed of taro aerial parts, young cassava leaves, young cashew leaves and brown rice flour (with or without banana slices), versus a traditionally used broiler feed diet was studied. Results - Cricket mortality was low in all diets, except the two cashew-based diets. Total biomass was significantly higher under the broiler feed, in addition to the two diets containing a combination of cassava leaf powder and brown rice. Yet, crickets fed with the taro diet had the highest percentage of protein. Concerning the breeding system cost, units using cassava leaves were the cheapest ones. Conclusion – Diets based of cassava leaves seems to be the most promising ones. Nevertheless, to produce crickets with a high body mass and a high protein level, a new experiment must be realised in which the cassava leaf maturity will be adapted to fit with the cricket growth stage. Moreover, to reduce the cost of the breeding units, handmade local products should be used instead of purchased components. [less ▲]

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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 ▲]

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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 ▲]

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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 ▲]

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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 ▲]

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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 ▲]

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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 ▲]

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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 ▲]

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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 ▲]

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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 ▲]

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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 ▲]

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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 ▲]

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