Functional properties of chemically modified proteins of sardine meal defatted with 1-propanol

After extracting oil from sardines using 1-propanol, the proteins of the re sidual defatted meal were chemically modified using either succinylation, a cetylation, maleylation or phosphorylation, and their functional properties were investigated. The solubility and viscosity of defatted meal protein w as improved by succinylation and maleylation. The modified proteins had hig her emulsifying activity. Succinylated and maleylated proteins had superior emulsifying capacity and emulsion stability. The nutritional qualities of the modified proteins, based on their amino acid compositions, were somewha t decreased. Modification of the electrostatic and hydration characteristic s of protein molecules to a more highly charged state by succinylation and maleylation could be effective in improving the functional properties of de fatted meal proteins.