Environ Exp Biol (2017) 15: 173–176

Fatty acid profiles of fermented soybean prepared by Bacillus subtilis and Rhizopus oligosporus

Abstract

There are various types of fermented soybean products in Asia including ^Natto (Japan), ^Jang (Korea), ^Kinema (India), and ^{Thua Nao} (Thailand). For these products, bacteria mostly belonging to the genus ^Bacillus (i.e., ^{Bacillus subtilis}) are used. This study was aimed to use a co-culture between B. subtilis and Rhizopus oligosporus in preparing the fermented soybean. Initially, the raw soybeans were washed, sterilized by autoclaving, and inoculated with these inocula; for this, three different ratios between B. subtilis and R. oligosporus were used (100:0, 50:50, and 0:100). The fermentation was carried out at 30 °C for 3 days, and fatty acid concentration was determined. Results showed that palmitic, stearic, oleic, linoleic, and eicosanoic acids were present in the fermented soybeans products. The major fatty acids present in all samples were oleic and linoleic, ranging between 30.49 to 34.07 and 50.35 to 53.72% of total fatty acids, respectively.