Enhanced functionality of pea-rice protein isolate blends through direct steam injection processing.

Direct steam injection (DSI) processing with pH adjustment was investigated to enhance the functionality of pea-rice protein isolate blends (PR). Protein slurries at concentration of 5%(w/w) of commercial pea and rice protein isolates in the ratio of 2:1(w/w) across a range of steam temperatures (66-107°C) and pH values (2-11) were studied. After DSI treatment, the PR were freeze-dried to obtain the final dry protein powder. Based on protein solubility profiles, the optimal DSI processing conditions were 107°C and pH 11. Available lysine was not reduced (P>0.05) in the blend. Solubility (from 3 to 41%, at pH 7), emulsifying activity index (from 5.9 to 52.5m2 /g), foam stability (from 68.2 to 82.8%), and oil holding capacity (from 1.8 to 4.9g/g) values increased (P<0.05) compared to the untreated PR. DSI can modify the functionality of PR without affecting the essential amino acid composition.