THE FUNCTIONAL PROPERTIES OF RICE PROTEIN ISOLATE EXTRACTED BY SUBCRITICAL WATER

Abstract

Subcritical water extraction is a unique technique to produce protein isolate from foodstuffs. In this study, the protein isolate from rice bran and rice (in a proportion of 8:92) was treated by subcritical water extraction. The main independent variables in extraction process were: the extraction time (15, 30, 45 min) and the extraction temperature (110, 120, 130 ºC). The Solubility, foaming capacity and foaming stability, emulsifying activity and emulsion stability and the degree of hydrolysis of the rice protein isolate were determined at 120 ºC in different contact time (15, 30, 45 min). The optimum subcritical water extraction condition was obtained at 120 ºC in 45 min. Better functional properties were observed in subcritical water extraction products that indicated this method can be applied as a novel alternative technique to modify the properties of rice proteins isolate for the functional purposes in future.