Effect of emulsifiers on the preparation of food-grade oil-in-water emulsions using a straight-through extrusion filter

This paper describes the preparation characteristics of food-grade soybean oil-in-water (O/W) emulsions using a novel straight-through extrusion filter, named a silicon straight-through microchannel (MC). Polyglycerol fatty acid ester (PGFE), polyoxyethelene sorbitan monolaurate (Tween 20), and sucrose fatty acid ester were tested as emulsifiers. Optical observations of the emulsification process exhibited that monodisperse oil droplets were stably formed from an oblong straight-through MC for PGFE and Tween 20. The effect of the emulsifier on the straight-through MC emulsification behavior is discussed. The selected PGFE- and Tween 20-containing systems enabled us to prepare monodisperse O/W emulsions with droplet diameters of 3839 mum and coefficients of variation below 3% using an oblong straight-through MC with a 16 mum-equivalent channel diameter.