Process for the preparation of undenatured vegetable proteic isolates

A process for the preparation of undenatured protein isolates starting from vegetable protein material comprising:

• i) suspending said vegetable protein material in water at pH higher than 7 in a diffuser under pressure with a pulsed-air mixing system, thus forming an alkaline aqueous suspension;
• ii) treatment of said alkaline aqueous suspension formed in step i) in order to separate a solid residue comprising fiber and starch therein contained, obtain an aqueous suspension substantially free from starch and fiber;
• iii) adding an organic weak acid to the alkaline aqueous suspension formed in step ii), up to a pH ranging between 6.5 and 3.0;
• iv) introducing the acidified suspension coming from step iii) in a CO2 dissolver thus forming a gelatinous proteic mass and whey;
• v) separating whey from said gelatinous proteic mass and deaerating thereof;
• vi) dehydrating of said deaerated gelatinous proteic mass coming from step v) to obtain the desired protein isolate,
• wherein each step from i) to vi) is carried out at room temperature or anyway at a temperature lower than 65° C.