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Functional properties such as nitrogen solubility, emulsifying property, foaming property, and water and oil absorption of sesame and perilla protein isolates were determined at pH range of 2-10 and ionic strength of 0-0.5 M NaCl. Nitrogen solubility of protein isolates in distilled water showed minimum value at pH 6.0 in sesame and at pH 4.0 in perilla and soybean protein isolates, and significantly increased above pH 8.0 in all samples. Addition of 0.1 M NaCl solution increased nitrogen solubility, however, decreased in 0.5 M NaCl solution. Emulsion activities of all the protein isolates showed minimum value at pH 4.0 and increased in O.1M NaCl solutions while it was reduced in 0.5 M NaCl solutions. The perilla protein isolate showed higher emulsion activity than that of soybean and sesame protein isolates at above pH 6.0. Foaming capacities of sesame and perilla protein isolates were lower than soybean protein isolate and generally all of the samples showed higher profiles in NaCl solutions. The foaming stability of soybean isolate decreased abruptly in 10 min, while it was slowly decreased for sesame and perilla isolates during initial 30 min. Oil absorption capacity of perilla protein isolate was higher than that of sesame and soybean protein isolates. Water absorption capacity was similar among the three samples studied.
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