title: Removal of soy protein-bound phospholipids by a combination of sonication, β-cyclodextrin, and phospholipase A2 treatments.
abstract: One of the contributing factors to generation of off-flavours in soy protein isolate (SPI) during storage is autoxidation of residual amounts of phospholipids present in SPI. Thus, removal of phospholipids from SPI is a likely first step to improve its flavour stability and enhanced utilisation of SPI in food products. We describe a β-cyclodextrin-based (βCD) process to remove protein-bound phospholipids and free fatty acids in SPI. Treating SPI solution (8%) with 10mM βCD alone at pH 8.0 decreased the phospholipid content of SPI by about 36%. A greater than 99% removal of phospholipids and free fatty acids was achieved by using a combination of treatments involving sonication of the SPI solution for 5min at 50°C followed by treatment with phospholipase A2 and βCD. SPI prepared by this method was white in colour. The results presented here offer a process for removing residual off-flavour causing phospholipids from soy protein.
authors.affiliation: Department of Food Science, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Akshay
authors.initials: A
authors.lastname: Arora
authors.affiliation: Department of Food Science, University of Wisconsin-Madison, Madison, WI 53706, USA. Electronic address: sdamodar@wisc.edu.
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Damodaran
keywords: Beta-cyclodextrin; Off-flavour; Removal of soy phospholipids; Soy protein isolate