Alcoholic chestnut fermentation in mixed culture. Compatibility criteria between Aspergillus oryzae and Saccharomyces cerevisiae strains.

The main objective of the present work consisted in the transfer to the case of the chestnut of a rice fermentative process that carried out to the Japanese traditional way to lead to an alcoholic bagasse, the moromi, capable of obtaining distilled. This way, selection assays of amylolitic Aspergillus oryzae strains and studies of compatibility between microfungi and yeast were carried out. These mixed cultivations were performed operating in batch submerged culture. Later on, using solid state system (chestnut, microfungi, yeast), a fermentative fed-batch process (koji, moto, moromi) was defined. By means of this approach a yield of 70% was reached in the conversion of total carbohydrates in ethanol. Also, the time required by the traditional operation was reduced in half.