During the processing of tempe, fermentation process occurs twice: (1) First fermentation at soaking: to grow bacteria for producing organic acids such as lactic acid and acetic acid, (2) Second fermentation that is carried out by Rhizopus sp.
The quality of tempe is influenced by: raw materials, processing, and type of inoculum used. There are three species of Rhizopus which are used frequently in tempe fermentation: Rhizopus oligosporus, Rhizopus oryzae, and Rhizopus stolonifer.
Presented by Ir. Nurrahman, MSi at Temu Ilmiah Masyarakat Pangan Jawa Tengah, Maret 2012