Warji Warji, Tamrin Tamrin and Sapto Kuncoro
Study Program of Agricultural Engineering, Faculty of Agricultural, University of Lampung, Lampung, Indonesia
Warji, W., Tamrin, T. & Kuncoro, S. (2025). The Manufacturing nanofibrils of black soybean and testing of cross polarizers. Bulg. J. Agric. Sci., 31(1), 69–74
Black soybean has a high protein content, has a more savory taste, contains antioxidants, can lower cholesterol levels, improve digestion and other benefits for the health of the human body. Black soybean is generally used as an ingredient of soy sauce, but can be processed into various types of food such as tempeh, tofu, milk, tauco and black soybean flour. Black soybean flour contains high protein so it has the potential to be a protein isolate.
The purpose of this study was to process black soybeans into soy protein isolate and convert to nanofibrils. Black soybeans was converted into soy flour using hammer mill and then five time defatted by hexane solution. Soybean meal without lipid was processed into soy protein isolate.
The material content in the form of black soybean seeds is 100%, the material content decreases during the process of isolation to 97% in the form of soybean meal, 63.05% in the form of defatted black soybean flour and 25.43% in the form of black soybean protein; consisting of 0.28% fat, 22.51% protein, 0.52% ash and 2.12% carbohydrates. The final protein content of black soybean protein in this study was about 88.49% on a dry basis so that the resulting protein can be classified as soy protein isolate because its value is close to 90%. Nanofibrils can be observed with a cross polarizer. Nanofibrils produced is long and branched in a diameter of several nanometers, obtained by heating the SPI suspension at pH 2.0 for 16 h.