43-10 |
Uses of quillaja saponins in stabilizing oil in water emulsions (O/W) for potential applications in food industry |
J. G. ALARCÓN1, R. San Martín, and M. T. Cesário. (1) Departamento de Ingeniería Química y Bioprocesos, Pontificia Universidad Católica de Chile, Vicuña Mackenna 4860, Macul, Santiago de Chile, 6904411, Chile Quillaja saponins are natural surfactants approved by the FDA as food additives. They are extracted from the Chilean tree Quillaja saponaria Molina. Quillaja saponins consist of glycosides linked to triterpene aglycones. Glycosides are the hydrophilic radical and the triterpene is the lipophilic part of the molecule. Quillaja saponins stabilize oil in water emulsions (O/W) because of their good hydrophilic properties (HLB > 13). In this study, the emulsifying properties of quillaja saponins were evaluated preparing emulsions and studying the stability and rheological properties of them. Emulsions were prepared with different concentrations of quillaja extracts as the surfactant (0.2, 0.5 y 1 % w/w), soybean oil as the oil phase (30, 50 y 70 % w/w) and xanthan gum as thickener (0 y 0.2 % w/w). The results were compared to emulsions prepared with sucrose esters. Emulsion stability was evaluated following particle size and creaming with time. The study showed that stable emulsions are obtained. The only exception was for emulsions containing 30% of soybean oil which presented rapid creaming. In order to improve their stability, the viscosity of the continuous phase was increased using larger quantities of xanthan gum (0.5 % w/w). This way stable emulsions were obtained for more than 120 days (duration of the experiment). Particle size of oil droplets did not increase with time. Emulsions prepared with sucrose esters showed similar characteristics to those prepared with saponins. Taking into account the importance of natural surfactants in food industry, quillaja saponins can be a good alternative for stabilizing O/W emulsions. Keywords : Natural surfactants, saponins, emulsions
Session 43, New Products & Technologies: Ingredients
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