Preparation of fine W/O/W emulsion through membrane filtration of coarse W/O/W emulsion and disappearance of the inclusion of outer phase solution

Preparation and evaluation of water-in-soybean oil–in-water emulsions by repeated premix membrane emulsification method using cellulose acetate membrane

“…After 7 days storage, less than 65 % of encapsulation efficiency was obtained for the emulsions prepared at 3 passes of homogenization cycles and below. Shima et al (2004b) the encapsulation efficiency of PTSA greater than 90 % in the homogenization of a W/O/W coarse emulsion through disposable cellulose acetate filter with a mean pore size of 0.700-3.000 μm. The encapsulation efficiency was less than 65 % at 3 passes of homogenization cycles and below, because the mean size of oil drops were larger than the emulsions prepared at 4 and 5 passes through the membrane, as shown in Fig.…”

“…The reasons for the decrease in the encapsulation efficiency of the emulsion prepared at high surfactant concentration remains unclear. One of the major reasons may be Ostwald ripening (Shima et al 2004b). Ng et al (1996) suggested that the alleviators of Ostwald ripening are (a) an oil-insoluble solute in the inner-water phase and (b) an osmotic pressure excess more of the outer-water phase compared to the inner water phase.…”

Microstructured Devices for Preparing Controlled Multiple Emulsions

“…Membrane emulsification is also used for preparing a fine W/O/W emulsion from a coarse W/O/W emulsion that has been prepared using conventional two-step homogenization [51][52][53]. The preparation of multiple emulsions by membrane emulsification has recently been reviewed by Graaf et al [54].…”

Effect of the hydrophilic surfactants on the preparation and encapsulation efficiency in course and fine W/O/W type emulsions

“…A coarse W/O/W emulsion was prepared through a two-step homogenization using a rotor/stator homogenizer (Physcotron, Microtec, Tokyo, Japan) at 2.2 × 10 4 rpm for 2 min in the first step and at 1.0 × 10 4 rpm for 1 min in the second step. A disposable membrane filter cartridge was connected to a disposable syringe, and the coarse W/O/W emulsion was loaded in the syringe [6]. The syringe was then sealed and pressurized by nitrogen gas to filter the coarse W/O/W emulsion to produce a fine W/O/W emulsion.…”

“…The encapsulation efficiency of PTSA in the inner-water phase of a W/O/W emulsion was estimated according to our previous method [6]. The efficiency in percentage was defined by (m 0 − m out )/m 0 × 100, where m 0 is the amount of the marker loaded into the inner-water phase and m out is the amount of the marker leaked into the outer-water phase.…”