Combined effect of pH treatment and the extraction pH on the physicochemical, functional and rheological characteristics of amaranth (Amaranthus hypochondriacus) seed protein isolates. (15th August 2021)

• Record Type: Journal Article
• Authors: Das, Dipak; Mir, Nisar A.; Chandla, Narender Kumar; Singh, Sukhcharn
• Is Part Of: Food chemistry. Volume 353(2021)
• Publication Date: 2021-08-15
• Subjects: Amaranth protein isolate -- Functional characteristics -- Extraction pH -- Gelation dynamics -- Thermal characteristics; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2021.129466
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Extraction pH (9–11) and pH treatment favorably affected different characteristics of amaranth protein isolates (APIs). APIs obtained at pH 9 showed highest purity, solubility and lowest yield. Particle size was reduced when the treatment pH was increased. Storage modulus ( G' ) and loss modulus ( G" ) were found higher in APIs obtained at pH 9. Functional properties showed significant improvement when the extraction and treatment pH of APIs was maintained at 9. Abstract: Results for the effect of extraction pH and pH treatment on the functional, physicochemical, rheological and thermal characteristics of amaranth protein isolates (APIs) are reported in this study. Four amaranth protein isolates (P1, P2, P3 and P4) were prepared by varying the extraction pH (9–11). These four protein isolate samples were further treated at pH values from 3 to 9. The total protein content and purity of protein isolates were found to be higher for P1 than P2, P3 and P4 samples. The particle size of P1 was significantly ( p ≤ 0.05) higher (299.68 µm) than other samples. Solubility, emulsifying capacity and stability, foaming properties, water and oil binding capacities were higher for the P1 sample treated at pH 9. Gelation characteristics like storage modulus ( G' ) and loss modulus ( G" ) were higher for P1 samples. APIs obtained at extraction pH 9 (P1) also exhibited better thermal properties in comparison with other three samples.