Food Chemical Studies of Soybean Phospholipids

Part I. On the phospholipids of soybean and Miso

Abstract

The composition of phospholipids of soybean and its product such as Miso, Soysauce, Natto, and Koritofu were investigated by thin layer chromatography. Soybean contained at least six kinds of phospholipid including phosphatidylcholine and phosphatidylethanolamine. In Miso, only one spot was detected, which was considered as sterol glycoside or sterol glycoside fatty acid ester.
In order to make clear the difference of phospholipids of soybean and Miso, soybean phospholipids were treated with water extract of Koji and Aspergillus oryzae. All the phospholipids except spot 6 were decomposed by the action of the enzymes, accompanying formation of free fatty acids and water soluble phosphate. The residual spot was also detected in rice which was raw material of Koji. The results suggest that the phospholipid spot of Miso is the one contained in soybean and rice, which is not digested by the enzyme of Aspergillus oryzae.