Processed
Rhizopus oligosporus
S tier
Rhizopus oligosporus is the classic tempeh mould: a fast white mycelium that knits dehulled soybeans into a sliceable cake in about a day at warm room heat. It is chosen for a clean, nutty, mushroomy ferment and for a relatively low risk of the grey-black sporing that older cakes show. Most supermarket starter sachets are this species or a close mix built around it. Beans must be dry on the surface and warm, not swimming. Good oligosporus tempeh is white, smells of mushroom and fresh bread, and snaps clean. Black specks at the end of fermentation are spores, not dirt—but a sour, slimy cake is a failed incubator, not a variety character.
Track this ingredient
Characteristics
Preparations
Traits
History
Javanese tempeh makers selected white Rhizopus cakes later identified as R. oligosporus.
Western food science isolated oligosporus as the preferred pure tempeh culture.
Freeze-dried oligosporus sachets made home tempeh possible outside Indonesia.
Craft tempeh shops specified oligosporus for clean white cakes on soy and other legumes.