Abstract
This paper reports the effect of temperature on the production characteristics of soybean oil-in-water (O/W) emulsions by microchannel (MC) emulsification using different emulsifiers. The temperature of an emulsification module including an MC array chip (MS104) was controlled between 10°C and 70°C. Sodium oleate, pentaglycerol monolaurate (PGM), and polyoxyethylene sorbitan monolaurate (Tween 20) were used as emulsifiers. The contact angle of the dispersed phase on the channel wall exceeded 130° and decreased gradually as the temperature increased. Monodisperse O/W emulsions with coefficients of variation (CV) below 6% were produced, independent of the temperature applied and the type of emulsifier used. The resultant droplet diameters, which ranged between 30 μm and 36 μm, decreased gradually as the temperature increased. The resultant droplet diameter was also almost constant below a critical flow velocity of the dispersed phase in a channel. The critical flow velocity increased with increasing operating temperature. The sodium oleate-containing system had a critical flow velocity and a maximum droplet generation rate considerably higher than those for Tween 20- and PGM-containing systems at each temperature.
