Valorization of noni (Morinda citrifolia) seeds as source of a protein concentrate and its physicochemical, funcional and structural characterization

Abstract

The noni juice industry produces a large volume of seeds as by-products, which contain proteins that can be recovered to be used as food ingredients. The aims of this study were the valorization of noni seeds as source of a protein concentrate (NSPC) and their physicochemical, functional, and structural characterization. NSPC was produced by alkaline extraction and isoelectric precipitation, obtaining a powder with a protein content of 76.59%, whose values of the color parameters were L* = 55. 32%, a* = 4.60%, and b* = 19.09. Water (WHCa) and oil (OHCa) holding capacities of the NSPC were 4.36 g H2O/g protein and 11.69 g oil/g protein, respectively, while the emulsifying activity, emulsion stability, foaming capacity, foaming stability, least gelling concentration, and in vitro digestibility were, 29.20%, 50.00%, 180.33%, 94.60%, 4.00%, and 78.51%. Glutelins (64.62%) were the main protein fraction of the NSPC. Hence, NSPC could be used as ingredient for human food products as bread, soups, salad dressings, mayonnaise, and processed meat products.