Emulsification by chemically modified ovalbumin

Enhancement of emulsifying properties of a model protein, ovalbumin, was achieved by covalent attachment of hydrophobic groups using various esters of N-hydroxysuccinimide. It was found that the resulting modified proteins were much better emulsifiers than the native ovalbumin, even at low modification degree (20-30% of available amine groups): in tetradecan-water emulsions oil separation was observed within a few hours, when 0.7 mg/ml native ovalbumin was used, compared to about one month until separation was observed when the modified proteins were used. The use of highly modified proteins prevented completely oil separation (at least two months): for example, emulsions prepared with 81% modified proteins with C8, c6,showed no change in droplet size distribution even 50 days after preparation. The effect of chain length on emulsification was also investigated: an optimal chain length (C₈) was found, for both low and high modifications.