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Dispersions are unstable from the thermodynamic point of view; however, they can be kinetically stable over a large period of time, which determines their shelf life. This time span needs to be measured in order to ensure the best product quality to the final consumer. “Dispersion stability refers to the ability of a dispersion to resist change in its properties over time.” D.J. McClements.〔(“Food emulsions, principles, practices and techniques” CRC Press 2005.2- M.P.C. Silvestre, E.A. Decker, McClements Food hydrocolloids 13 (1999) 419-424 )〕 ==Destabilisation phenomena of a dispersion== These destabilisations can be classified into two major processes: # Migration phenomena : whereby the difference in density between the continuous and dispersed phase, leads to gravitational phase separation: # *Creaming, when the dispersed phase is less dense than the continuous phase (e.g. milk, cosmetic cream, soft drinks, etc.) # *Sedimentation, when the dispersed phase is denser than the continuous phase (e.g. ink, CMP slurries, paint, etc.) # Particle size increase phenomena: whereby the size of the dispersed phase (drops, particles, bubbles) increases # *reversibly (flocculation) # *irreversibly (aggregation, coalescence, Ostwald ripening) 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Dispersion stability」の詳細全文を読む スポンサード リンク
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