Physicochemical and Some Functional Properties of Melon ( <scp> <i>Cucumeropsis mannii</i> </scp> ) Protein Isolate in Comparison With Pea ( <scp> <i>Pisum sativum</i> </scp> ) Protein

Abstract

ABSTRACT The increase in the world population has necessitated the search for newer sources of plant protein, such as Cucumeropsis mannii (melon). In this study, Cucumeropsis mannii protein isolate (MPI) was extracted and characterized in comparison to the pea protein isolate (PPI). The methionine content of the Cucumeropsis mannii protein isolate (4.93 g/100 g protein) was about four times that of the pea protein. Arginine and glutamic acid were the major amino acids in the melon protein. The β ‐sheet secondary structure was the dominant structure in the proteins. Melon protein isolate contains an acidic legumin subunit. Fluorescence and hydrophobicity data suggested a folded structure for the Cucumeropsis mannii protein isolate when compared to the pea protein. Gel electrophoresis indicated six polypeptide bands (35, 70, 80, 120, 130, and 170 kDa) in the melon protein isolates. In contrast to the pea protein, melon protein had a maximum of 85% protein solubility at pH 3. The emulsifying stability of the proteins significantly differed ( p &lt; 0.05) at pH 7. Higher emulsifying capacity and stability were observed in melon than in pea proteins under acidic and alkaline media. MPI displayed a higher solubility profile than PPI at all pHs. Weaker gel formation was observed in the melon protein. It could be concluded that melon protein isolate would be a potential functional ingredient in the food system sequel to the highlighted properties.