Gulzar M, Taylor JR, Minnaar A. Influence of extraction pH on the foaming, emulsification, oil-binding and visco-elastic properties of marama protein.
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2017;
97:4815-4821. [PMID:
28374434 DOI:
10.1002/jsfa.8351]
[Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/30/2017] [Accepted: 03/30/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND
Marama bean protein, as extracted previously at pH 8, forms a viscous, adhesive and extensible dough. To obtain a protein isolate with optimum functional properties, protein extraction under slightly acidic conditions (pH 6) was investigated.
RESULTS
Two-dimensional electrophoresis showed that pH 6 extracted marama protein lacked some basic 11S legumin polypeptides, present in pH 8 extracted protein. However, it additionally contained acidic high molecular weight polypeptides (∼180 kDa), which were disulfide crosslinked into larger proteins. pH 6 extracted marama proteins had similar emulsification properties to soy protein isolate and several times higher foaming capacity than pH 8 extracted protein, egg white and soy protein isolate. pH 6 extracted protein dough was more elastic than pH 8 extracted protein, approaching the elasticity of wheat gluten.
CONCLUSION
Marama protein extracted at pH 6 has excellent food-type functional properties, probably because it lacks some 11S polypeptides but has additional high molecular weight proteins. © 2017 Society of Chemical Industry.
Collapse