Isolated soy protein (30 g) was dispersed in deionized water. The pH was adjusted to 8.5 with 1 N NaOH and the dispersion was heated to 50° C. Octadecenyl succinic anhydride (36 g) was melted at 75° C. for 1-2 hours before dissolving in tetrahydrofuran (100 ml). When the temperature of the soy dispersion reached 50° C., the ODSA/THF solution was added in 5 ml increments over 1 hour with concurrent adjustment of pH to 8.5 with 1 N NaOH. The solution was stirred for an additional hour to hydrolyze any unreacted anhydride. Protein was recovered by precipitation at pH 4.0 with 1 N HCl. The precipitate was washed and filtered three times with deionized water. The protein was dried at 60° C. and finely ground.
