Izegem, Belgium
Izegem, Belgium

Time filter

Source Type

Tavernier I.,Ghent University | Doan C.D.,Ghent University | Doan C.D.,Can Tho University | Van De Walle D.,Ghent University | And 3 more authors.
RSC Advances | Year: 2017

The main objective of this study was to investigate the effect of combining a high-melting wax (sunflower wax or rice bran wax) with a low-melting wax (berry wax or BEW) on the crystallization and gelation behavior of the corresponding wax-based oleogels in rice bran oil (RBO). Sunflower wax (SW) and rice bran wax (RBW) have a similar chemical composition but a very different crystallization behavior. Therefore, SW and RBW were also combined in a wax-based oleogel to examine the occurrence of co-crystallization and/or crystal co-existence. The thermal and gelation behavior of the binary blends in rice bran oil (5% w/w total concentration of wax) were investigated with differential scanning calorimetry (DSC) and rheological measurements, showing sequential crystallization and gelation for the SW/RBW : BEW wax-based oleogels and simultaneous crystallization and gelation for the SW : RBW wax-based oleogels. Oscillatory shear and hardness measurements revealed the reinforcement of the high-melting wax crystal network with the addition of the low-melting berry wax. X-ray diffraction (XRD) measurements in both the long-spacing and the short-spacing region showed the occurrence of crystal co-existence, rather than co-crystallization, which was confirmed with polarized light microscopy (PLM). Two different crystal morphologies could be discerned for all three combinations (RBW : SW, SW : BEW and RBW : BEW). We hypothesized that the improved rheological properties could be attributed to sintering, a process in which the low-melting BEW crystals form solid bonds between the crystals of the high-melting waxes. As such, a cohesive network is formed, resulting in an increased hardness of the bi-wax-based oleogels. This research provides the opportunity to minimize the amount of wax necessary in creating semi-solid materials with a wide variety in rheological and textural properties. © The Royal Society of Chemistry.

Patel A.R.,Ghent University | Schatteman D.,Ghent University | Lesaffer A.,Vandemoortele R and nter | Dewettinck K.,Ghent University
RSC Advances | Year: 2013

We report a unique approach of using a water soluble polymer (a cellulose derivative) to generate organogels via a facile, low temperature process. This finding is an important step towards the development of liquid oil-based soft matter systems for applications in non-bio and bio-related fields. © 2013 The Royal Society of Chemistry.

Patel A.R.,Ghent University | Rodriguez Y.,Vandemoortele R and nter | Lesaffer A.,Vandemoortele R and nter | Dewettinck K.,Ghent University
RSC Advances | Year: 2014

We report a new approach of using dispersed water phase gelation as a mode to create oil continuous emulsion gels. The low temperature gelation property of synergistic hydrocolloid combinations was exploited to develop elastic soft solids using only food-grade components. © 2014 The Partner Organisations.

Patel A.R.,Ghent University | Dumlu P.,Ghent University | Vermeir L.,Ghent University | Lewille B.,Ghent University | And 2 more authors.
Food Hydrocolloids | Year: 2015

We report the fabrication of multiple emulsions where both the enclosed and the external water phases are structured using a combination of two non-gelling biopolymers. Emulsions (with gelled inner water droplets and gelled water continuous phase) were created using a simple 'one-step' process where the oil phase (triglyceride oil and polyglycerol polyricinoleate) and the water phase (containing a combination of locust bean gum and carrageenan) were emulsified at an elevated temperature (70°C) followed by cooling to room temperature. The temperature triggered gelling of the synergistic biopolymer combination led to the formation of structured emulsions on cooling. Flowable to self-standing emulsion gels could be prepared by changing the total concentration of polymers (and the ratios of the individual polymers) as confirmed from low amplitude oscillatory shear rheology and creep recovery measurements. The cryo-scanning electron microscopy images of freeze-fractured emulsion samples revealed the presence of gelled inner water droplets. Further, when subjected to heating and cooling cycles, emulsions displayed reversible rheological changes which could be tuned by simply changing the total polymer concentration and the proportions of individual polymers. Such biopolymer-based structured emulsions with interesting microstructure and rheological properties could find potential applications in bio-related fields like food structuring. © 2014 Elsevier Ltd.

Patel A.R.,Ghent University | Schatteman D.,Ghent University | De Vos W.H.,Cell Systems and Cellular Imaging CSI | De Vos W.H.,University of Antwerp | And 2 more authors.
Journal of Colloid and Interface Science | Year: 2013

We report the preparation and rheological characterization of oleogels and oleogel-based emulsions prepared using shellac as a structurant. Shellac showed excellent oleogelation properties, resulting in liquid oil gelation at a concentration as low as 2. wt%. Microscopic evaluation of these oleogels indicated that the oil gelation was a result of physical entrapment of liquid oil in crystal networks of shellac formed by cooling the hot oil dispersions of shellac to room temperature. The rheological behaviour of shellac oleogels to varying deformation (% strain) was comparable to oleogels prepared using a commercial crystal starter. The cooling and shear rate showed a significant effects on the rheological properties of formed oleogels. The thermo-reversible, hysteresis, thixotropic and shear thinning properties of oleogels were evaluated by comparing rheological data obtained from rotational and oscillatory measurements. Shellac oleogels were further used as continuous phases to generate emulsifier-free w/o emulsions which surprisingly showed good stability over 4. months of storage. Microscopy and rheological evaluations of these emulsions were carried out to obtain more insight into its microstructures. © 2013 Elsevier Inc.

Loading Vandemoortele R and nter collaborators
Loading Vandemoortele R and nter collaborators