Influence of double enzymic hydrolyses on gluten functionality

Functional properties of chemically deamidated and/or double enzymically-treated gluten were studied. Performances of the modified glutens were compared to those of egg white proteins, casein, deamidated gluten and gluten submitted to deamidation plus single enzymic treatment. Higher nitrogen solubility index (>90%) was obtained after treatment of the gluten with the sequence pepsin + alcalase and deamidation + pepsin + papain. The sequence pepsin + papain has permitted the production of a gluten with foaming properties close to those of egg white. Deamidation + papain treatment leads to interesting emulsifying properties although different from those of casein. The results show that modified glutens present thresholds in the degree of enzymic hydrolysis (DH) for foaming and emulsifying properties (respectively 1.3% and 2.0%). For higher DH the stability decreases. © 1999 Society of Chemical Industry