Efficacy of the antimicrobial peptide nisin in emulsifying oil in water

Nisin is an amphiphilic, antimicrobial peptide that has found application a s a preservative in the food industry. Evaluation of nisin as an emulsifier was accomplished by measuring its ability to stabilize dispersed oil dropl ets in water. This was achieved by monitoring the time-dependent electrical conductivity of the dispersion. Nisin solutions at concentrations of 0, 0. 5, 1, 5, and 10 mg/ml were used to prepare emulsions, by homogenization of a volume of nisin solution and corn oil. While nisin showed significant emu lsifying capacity in comparison to Tween(R) 80 and beta-casein, its emulsif ying properties were found to be highly concentration- and pH-dependent.