PURPOSE: To preserve the subject taros directly edible for a long period of time by putting water-washed taros in an aqueous solution of acetic acid, etc., subjecting to boiling-sterilizing treatment, washing with water, putting in a bag together with a specific controlling aqueous solution, sealing in vacuum, putting into hot water and cooling.

CONSTITUTION: Taros such as sufficiently water-washed taro, etc., are put in an aqueous solution of acetic acid or lactic acid at pH 2.0-3.0 and subjected to boiling-sterilizing treatment for 20-30min, then washed with water for about 30min, thus put in a bag together with a mixed controlling aqueous solution of lactic acid, sodium lactate, sugar and salt at pH 3.5-4.5 and sealed in vacuum, then dipped in hot water at ≥80°C for 15-25min, thus cooled to perform the aimed preservation for a long period of time (≥30 day).