Physicochemical Properties of Quinoa (Chenopodium quinoa Willd.) Protein Isolated from Black, Q12, and Titicaca Seed

Abstract

Background:: Quinoa was cultivated in different parts of the world because of the water crisis. On the other view, proteins from plant sources have attracted significant interest. One of the sustainable protein sources is quinoa protein. Objective:: The aimof this study was to isolate quinoa protein and determine physicochemical properties for its use in the food industry Methods:: Quinoa Protein Isolates (QPIs) were separated from Quinoa Seed (QS) varieties (Black- -QS, Q12-QS, and Titicaca-QS). The particle size, FTIR, SEM, emulsion activity and stability, protein solubility, and gelation properties were assessed. Results:: The Q12-QPI had the highest average particle size, 945 μm. The Black-QPI and Titicaca (T)-QPI had a higher protein content (87.32 ± 1.93, 87.84 ± 1.62% w/w), respectively, and a more condensed structure. The surface morphology of Black-QPI and T-QPI showed regular flat and compact surfaces with some small aggregates. Black-QPI had the most negative zeta potential charge (-38.8 ± 0.03) and stability among the TQPIs. Emulsion capacity was equal among the samples, but emulsion stability was the greatest value (34.48 ± 8.1) in T-QPI. The protein solubility ratio was 70.72, 70.0, and 69.27% in Q12-QPI, T-QPI, and Black-QPI, respectively. The higher elastic performance of Q12-QPI and T-QPI than Black-QPI was seen during the heating steps in the gelation stage. Conclusion:: The suitable nutritional and functional resources of Titicaca quinoa protein make it an appropriate candidate to use as a safe food additive