Drying methods affect physicochemical and functional properties of quinoa protein isolate.
Quinoa protein possesses great amino acid profiles and can be a potential food ingredient with broad applications. The objective of this study was to investigate the effect of different drying methods, namely freeze drying, spray drying, and vacuum drying on the functional and physicochemical properties of quinoa protein isolate, e.g., morphology, amino acid composition, SDS-PAGE profile, sulfhydryl/disulfide content, secondary structure, surface hydrophobicity, and thermal stability. The freeze-dried protein exhibited the highest emulsification capacity and stability and oil binding capacity, which was contributed to its higher surface hydrophobicity, while the spray-dried sample had the highest solubility and water absorption capacity at pH 7. Gels (8%) prepared with the freeze-dried protein had higher elastic and viscous modulus than that from others. The freeze-dried protein had the highest maximal denaturation temperature but lowest enthalpy, which may be attributed to its higher amount of random coil but lower percent of regular α-helix and β-sheet structures. Overall, quinoa protein isolate from different processing methods demonstrated distinct functional properties. This information will be useful to optimize quinoa protein production and benefit its applications.
['Shen|Yanting|Y|', 'Tang|Xiao|X|', 'Li|Yonghui|Y|']
D000596:Amino Acids D027465:Chenopodium quinoa D003890:Desiccation D004591:Electrophoresis, Polyacrylamide Gel D004655:Emulsions D005612:Freeze Drying D005782:Gels D006863:Hydrogen-Ion Concentration D057927:Hydrophobic and Hydrophilic Interactions D010940:Plant Proteins D014674:Plant Proteins, Dietary D011489:Protein Denaturation D017433:Protein Structure, Secondary D012995:Solubility D013696:Temperature D014618:Vacuum D014783:Viscosity
Drying methods Functional properties Quinoa protein isolate Physicochemical properties Plant protein