PURPOSE: To produce an absorption/putrefaction preventing agent for a remaining liq. in a dust box for an empty can provided at a soft drink vending machine and to provide a treating method of the remaining liq. using the agent.

CONSTITUTION: The absorption/putrefaction preventing agent 1 for the remaining liq. is composed of a sodium polyacrylate capable of absorbing and solidifying the remaining liq. and a sodium benzoate for preventing the putrefaction of the remaining liq.. The mixing ratio is 10:1, and the use amount of the sodium polyacrylate is preferably about 1g and that of the sodium benzoate is about 0.1g per 40ml of remaining liq. Then, a wrapping bag 2 is further used. The wrapping bag 2 wraps the absorption/putrefaction preventing agent 1 for the remaining liq. consisting of the sodium polyacrylate and the sodium benzoate. In this way, a handling of the remaining liq. is improved by solidifying the remaining liq., and a preventing effect on the leakage of the remaining liq. in an emergency is obtained. Moreover, a sanitary administration such as deodorization and sterilization is attained when adding a bactericide.