| Abstract
| - The objective of this study was to examine the effects of added xanthan gum, guar gum, orκ-carrageenan on the formation and properties of emulsions (4 wt % corn oil) formed with anextensively hydrolyzed commercial whey protein (WPH) product under a range of conditions. Therate of coalescence was calculated on the basis of the changes in the droplet size of emulsionsduring storage of the emulsions at 20 °C. Compared with the emulsion made without the addition ofpolysaccharides, the rate of creaming and coalescence in emulsions containing xanthan gum, guargum, or κ-carrageenan was markedly enhanced with increasing concentration of polysaccharidesduring storage for up to 7 days. At a given concentration, the rate of coalescence was highest in theemulsions containing guar gum, whereas it was lowest in the emulsions containing κ-carrageenan.All emulsions containing xanthan gum, guar gum, or κ-carrageenan showed flocculation of oil dropletsby a depletion mechanism. This flocculation was considered to enhance the coalescence of oil droplets.The different rates of coalescence could be explained on the basis of the strength of the depletionpotential, which was dependent on the molecular weight and the radius of gyration of thepolysaccharides. Keywords: Emulsions; hydrolyzed whey protein (WPH); coalescence; xanthan gum; guar gum;κ-carrageenan; depletion flocculation
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