Emameba and natto are both equally products of fermented soybeans, but it's only the difference in the fermentation process that creates their completely different tastes and traits.

In a nutshell, the fermentation process for natto uses only a single strain of natto to ferment; whereas tempeh fermentation uses a variety of strains, including Trichoderma, Rhizopus, and Aspergillus strains.

Therefore, natto is higher in individual nutrients. For example, natto is rich in thrombolytic kinase, which is effective in preventing cardiovascular embolism.

Tempeh, on the other hand, contains more diverse nutrients. Not only does it also contain thrombolysin (but at a lower level than natto), but also other vitamins such as resveratrol and B vitamins.