Production of vitamin B-12 in tempeh, a fermented soybean food.
Several varieties of soybeans contained generally less than 1 ng of vitamin B-12 per g. It was found that use of a lactic fermentation typical of tropical conditions during the initial soaking of the soybeans did not influence the vitamin B-12 content of the resulting tempeh. Pure tempeh molds obtained from different sources did not produce vitamin B-12. It was found that the major source of vitamin B-12 in commercial tempeh purchased in Toronto, Canada, was a bacterium that accompanies the mold during fermentation. Reinoculation of the pure bacterium onto dehulled, hydrated, and sterilized soybeans resulted in the production of 148 ng of vitamin B-12 per g. The presence of the mold, along with the bacterium, did not inhibit or enhance production of vitamin B-12. Nutritionally significant amounts of vitamin B-12 were also found in the Indonesian fermented food, ontjom.
D002170:Canada; D005285:Fermentation; D005516:Food Microbiology; D007214:Indonesia; D007778:Lactobacillus / Q000378:metabolism*; D012233:Rhizopus / Q000378:metabolism*; D013025:Glycine max; D013045:Species Specificity; D014805:Vitamin B 12 / Q000096:biosynthesis*
D014805:Vitamin B 12