Preparation of broad bean (Vicia faba L. minor) products. Part 2. Broad bean protein isolates from seed flour in the pH range below the isoelectric point

Broad bean protein isolates in aqueous solutions form stable gels after heating at pH values below the isoelectric point (pH 2-3) if they are extracted at the same pH. But the acid extraction is a time-consuming and expensive process. This paper outlines a new and simple procedure for the preparation of broad bean protein isolates in the acid pH range. It consists of a short extraction of seed flour at pH 7.5 (30 min) followed by an after-treatment at pH 2-3 (60 min) and gives the highest yield of acid treated broad bean protein isolates after a sudden acidification.