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The Rousseau Labs Food Research Lab Soft Matter Reseach and Technology (SMaRT) Lab Dérick Rousseau, Ph.D. Professor, Ryerson University Editor-in-Chief, Food Structure |
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The Rousseau Labs Food Research Lab Soft Matter Reseach and Technology (SMaRT) Lab Dérick Rousseau, Ph.D. Professor, Ryerson University Editor-in-Chief, Food Structure |
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 Gels and gel-based films and coatings based on bio-materials are widely used in products ranging rom adsorbants and barriers, to structural materials in tissue replacement and carriers of drugs or flavours. The main objective is to investigate novel methods of incorporation and release of specific materials from gels, films and coatings using a multidisciplinary approach incorporating benchtop experiment and simulation. Presently, research is focused on the design of biocompatible and self-supporting hydrogels based on gelatin and maltodextrin. Our approach is to use phase separation as a means of controlling hydrogel microstructure. The image on the left is a double phase separated image of a gelatin-maltodextrin hydrogel obtained via confocal laser scanning microscopy. This project is being performed in collaboration with Dr. Allan Paulson at Dalhousie University. |
| In food science and technology, self-assembly is a highly novel concept. Rather than create structures that are thermodynamically unstable at the micron level (a ‘top-down’ approach), and as a result must be kinetically stabilized, with nanostructuring, thermodynamically stable entities are created (a ‘bottom-up’ approach). Using this approach, nanometre-scale structures associate to form thermodynamically-stable microstructures responsible for functionality. Using this approach, we are designing and analyzing protein-based nanostructures. This project is being performed in collaboration with Drs. Chris Yip and Fred Keeley at the University of Toronto. |
| Our group is developing food-grade microemulsions (MEs) for the controlled delivery of nutraceuticals and for the development of novel nano-scale particles. While many agents can be used to make MEs, creation of food-grade systems is difficult, as few suitable non-toxic surfactants exist. Another hurdle in devising oil-in-water MEs is the choice of food-grade oils. We are currently assessing a number of oils to achieve our goal. |
 Our on-going research in chocolate is grounded in trying to understand the structural evolution of this material as a function of time and temperature, using a microstructural approach. In particular, we wish to understand how to control bloom formation (the greyish coating on ‘old’ chocolate). Our primary tool in this regard is atomic force microscopy. Please visit the page dedicated to chocolate microstructure for further information on this topic. |
 This project examines the role of colloidal crystals in understanding the kinetic stability of water-in-oil emulsions. Emulsions are transient entities, given their thermodynamic instability. However, the presence of colloidal particles can form a stabilizing “skin” at the interface of emulsions. These films stabilize emulsion by providing a steric barrier to interdroplet coalescence and by modifying the rheological parameters of the interface. At this point, however, the role of shear on interfacial particle morphology, size and charge remains poorly understood. This research examines the effects of flow and shear on interfacial colloids and their effects on the stability of emulsions by correlating colloid properties (size, microstructure, and charge properties) with kinetic stability. The image on the left is a polarized light microscopy image of the crystal phase of a water-in-oil emulsion. Note the crystal ‘rings’ around some of the droplets. This is called Pickering stabilization. |
 Our work on organogels focusses on the development of biocompatible lecithin-based systems. These systems are thermodynamically -stable, thermoreversible, viscoelastic and isotropic gels composed of lecithin, an apolar solvent phase, and polar solvent (water). The image on the left shows that these gels are selfsupporting. Their flow behaviour can be ‘tuned’, based on composition. Possible applications include: structuring agent for processed foods; structuring agent for cosmetics and as a controlled/sustained release of nutraceuticals and pharmaceuticals. |
| Official recommendations for vitamin D supplementation will go up substantially in a few years and thus foods other than milk and margarine must be considered for fortification. However, it is known that nutrient bioavailability can vary from food to food. The goal of this research is to evaluate the stability of vitamin D-fortified dairy foods and subsequently examine bioavailability. This research project is being conducted in collaboration with Dr. Reinhold Vieth at Mt Sinai Hospital in Toronto, Canada. |
 Raman spectroscopy provides a sensitive, non-destructive means of probing molecular structure in triglycerides, in both the solid and liquid states. We are using this technique to characterise lipid structure by focusing on specific groups, namely the C-H stretching region at 2850-2950 cm-1, the ester carbonyl stretching C=O region at 1780-1700 cm-1, and the C-C stretching region at 1150-1050 cm-1. We are analyzing a number of model and complex fats in order to extract relevant structural information. For example, through deconvolution, the figure on the left shows that there are 3 modes within the carbonyl region of the α-crystal of tristearin. Findings from this work are correlated with DSC and X-ray diffraction studies. |