Method for preparing fresh fish essence through processed freshwater fish leftover binary fermentation

The invention relates to a method for preparing a fresh fish essence through processed freshwater fish leftover binary fermentation. The method comprises the following steps: (1) crushing, namely crushing the processed freshwater fish leftover to be 40-60 meshes; (2) endogenous enxymolysis, namely activating fish cathepsin through ph and temperature control and Ca , appropriately hydrolyzing fish protein, and reducing the system viscosity; (3) sterilizing and curing, namely adding lentinus edodes stem powder, heating at 121 DEG C for 30 minutes, steering and softening fish bones, and stimulating calcium and bone collagen to dissolve out; (4) inoculated fermentation, namely inoculating a high-temperature yeast and lactobacillus bulgaricus binary fermentation agent to ferment; (5) homogenizing; (6) concentrating; and (7) after ripening. The method has the advantages that a problem that the processed freshwater fish leftover is difficult to utilize is solved; a product is stable in taste, natural in flavor, rich in nutrition and rich in various beneficial ingredients; and a production technology is unified, simple and easy to standardize.