Rice-Grown Rhizopus oligosporus Inoculum for Tempeh Fermentation

A method of growing Rhizopus oligosporus on cooked rice as the inoculum for the fermentation of soybeans into tempeh was described and evaluated. Isolated R. oligosporus spores on glass beads survived best at low temperature and intermediate humidity. The activity of the rice-grown inoculum to ferment soybeans into tempeh did not decrease appreciably when stored desiccated for one year at 4 C or room temperature. Bacterial contaminants as high as 108 counts per g of cooked soybeans did not seem to affect the fermentation.