A novel membrane emulsification method was used to prepare corn oil/water (O/W) emulsions (25 wt% oil phase) with sharp particle diameter distribution. When pre-emulsified O/W emulsions were used as dispersing fluids instead of the oil phase (corn oil+emulsifier), the membrane emulsification was carried out easily with a high emulsifying rate up to 3.5 m3/(h•m2-membrane). Mean particle diameters those of the mean pore sizes of the porous glass membranes used. The particle diameter of the emulsions decreased with increasing applied pressure or flux of the pre-emulsified emulsion through the membrane. Because of the high stability of the membrane emulsified emulsion particles, Iittle change in particle diameter distribution occurred over several weeks. The kind of emulsifying agent influenced the particle diameter distribution and the creaming rate.

PTFE (polytetrafluoroethylene) membrane filters were tested for preparing corn oil emulsions by the membrane emulsification method using a pre-emulsified emulsion. A hydrophilic PTFE membrane was used to prepare an O/W emulsion without any disturbance of the continuous phase. A W/O emulsion was prepared with a hydrophobic membrane filter in the same way. The higher the fiux of the pre-emulsified large particle emulsion via the membrane was, the higher the monodispersibility of the membrane enrulsified emulsion became. There was no limit to the emulsifying pressure or the emulsifying rate under the conditions tested. The mean particle diameters of the O/W and W/O emulsions were ca. 3 times the mean pore size of the membrane used.

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This study aimed to compare the physical properties of mayonnaise with its perceived texture. Model mayonnaises with the same composition were prepared under di#erent emulsifying conditions. Perceived textural properties of mayonnaise, such as hardness, fracturability, viscosity and adhesiveness, were evaluated by trained panels using the quantitative descriptive analysis method. Rheological properties and particle size distribution were measured instrumentally. Pearson's correlation coe$cients between textural attributes and physical properties were calculated. The storage modulus G' in the linear region showed significant correlations ( pῌ*.**+ or pῌ*.*+) with all of the sensory attributes. No significant correlation was observed between sensory attributes and viscosity-related properties, such as apparent viscosities and flow curve parameters. The particle size at +*ῌ cumulative volume had high correlations ( pῌ*.*+ or pῌ*.*/) with all of the sensory attributes studied.

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