Effects of soy lecithin levels and microfluidization conditions on properties of fish gelatin-based film incorporated with palm oil

Properties of film-forming dispersion (FFD) and emulsion film incorporated with palm oil containing soy lecithin at 50% and 75% (w/w, based on palm oil) and emulsified with different microfluidization pressures (6.89, 13.79 and 20.68MPa) and pass numbers (2 and 4) were investigated. Microfluidized FFD containing 50% soy lecithin showed the smaller oil droplet size. The lower water vapor permeability with higher tensile strength and elongation at break were found for films from microfluidized FFD (p<0.05). Films containing 50% soy lecithin had higher light transmittance and lower b∗- and ΔE∗-values than those containing 75% soy lecithin (p<0.05). Smooth surface and compact cross-section were observed in films from microfluidized FFD. Film from microfluidized FFD containing 50% soy lecithin showed higher thermal stability. Thus, the emulsion film with improved properties could be prepared from FFD using 50% soy lecithin with the aid of microfluidization.