Provided are: ice which has excellent cooling capacity; a production method therefor; a method for producing a cooled article; and a refrigerant. Also provided are: ice in a non-separating state; and a production method therefor and ice which satisfies conditions (a) and (b) and is from a liquid that includes an aqueous solution comprising a solute. (a) The temperature of the ice after melting completely is less than 0° C. (b) The rate of change of the solute concentration in the aqueous solution generated from the ice in the melting process is 30% or lower. The refrigerant includes the ice. The refrigerant also includes water which comprises the same solute as the solute included in the ice, wherein the ratio of the concentration of the solute in the ice and the concentration of the solute in the water is preferably 75:25 to 20:80.