2001.3.15A Novel Fractionation Method of Soy Protein and Reduction of Plasma lipids with Phytate-reduced -ConglycininSoy protein contains phytic acid, a kind of phosphorus compounds, about 2%. Phytic acid has been considered as an antineutrient, because, in large concentrations, it can reduced the bioavailability of minerals owing to its chelating effect. In addition phosphorus in b-conglycinin affects taste and texture of soy protein in many ways.
The first purposes of this study were removal of phytic acid from soy protein and preparation of phytate-removed soy protein. Phytase treatment was effective for this purpose and we were able to obtain low-phytate protein fraction.
Moreover, we noted very interesting fact that b-conglycinin and glycinin, which are the major component of soy protein, was separated very easily under the low phytate condition. In this manner, we developed novel fractionation method for phytate reduced b-conglycinin and glycinin by phytase treatment.
Then, we investigated the effects of phytate-reduced b-conglycinin and glycinin on the plasma lipids in rats. This result shows phytate-reduced b-conglycinin have lowering functions not only on plasma total cholesterol level, but also on plasma triglyceride level.
Therefore, it is expected that phytate-reduced b-conglycinin become a excellent food material for improvement of lifestyle related disease, particularly hyperlipidemia caused by high plasma triglyceride level.