<;P>;PROBLEM TO BE SOLVED: To provide a method for utilizing a food waste as a fodder by solving the problems possessed by a conventional hog raising by garbage, to provide a method for preserving the food waste without being rotted, and to provide a fodder containing a treated product of the food waste. <;P>;SOLUTION: The food waste is treated by the method including fermenting a raw material containing the food waste by a koji mold to afford a liquid product. The koji mold is the one of the genus Aspergillus having citric acid-producing activities. The liquid product contains the citric acid originated from the koji mold and has a pH of &le;5.5. <;P>;COPYRIGHT: (C)2011,JPO&INPIT