Studies on the Degradation Process of Soybean Protein during Miso Making

Part I Changes of water insoluble proteinpatterns during miso making

Abstract

Changes in electrophoretic patterns of water-insoluble proteins (WIP) of soybean during miso making were studied. On Tiselius patterns obtained in veronal buffer containing 7M urea, two large peaks with several small peaks were found in WIP of boiled soybean and of miso at initial stage of fermentation. During the fermentation, the faster-moving large peak disappeared forming sveral smaller peaks of different mobility, and thereafter the decrease of the slower-moving large peak proceeded resulting some increase of the faster-moving one. On calcium acetatecellulose paper electrophoretic patterns, components of WIP of boiled soybean was failed to separate each other, however, the mobility of the band increased during the fermentation of miso. On starch-gel electrophoretic patterns, several bands were observed for boiled soybean, while no distinct band was recognized for the sample after fermentation. No remarkable difference in amino acid content in WIP at each stage of fermentation.