PURPOSE: The time while the surface layer of raw meat passes through the temperature range of maximum ice-crystal formation is controlled to prevent frozen meat, especially raw meat to be frozen from discoloration with time when frozen or stored, thus keeping its scarlet color.

CONSTITUTION: Processed meat or raw meat products such as raw hamburger or meat ball is frozen wherein the time while the surface layer of the raw meat passes through the temperature range of the maximum ice-crystal formation is controlled to be 30min to 10hr to effect relatively gradual cooling, and preferably, the raw meat is kept tightly packed or kept from direct contact with the cooling air during the refrigeration.