Origin of solid-state fermentation

The Far East is clearly the place where solid-state fermentation has had, and still has, the greatest development. This is linked to the preparation of two staples of Far Eastern culture: sake and tofu. Traditionally, sake is made from steamed rice, which is then spread out on bamboo racks and inoculated with a leavening of Aspergillus oryzae mold, which develops by producing amylases. This stage takes place entirely in the solid phase. After growth, the resulting product, known as "koji", is crushed and mixed with water so that the starch can be hydrolyzed into glucose by the amylases, then inoculated with Saccharomyces sake yeast for alcoholic fermentation in the liquid phase. This process is very similar to that used in European brewing, where malting is...