PURPOSE: To obtain the title sheet, specifically acting, avoiding dehydration of foods, especially fishes and shellfishes and edible meat, change in color and wateriness of foods caused by oxidation during thawing, capable of preserving foods for a long period of time, comprising a semipermeable membrane part, a food part having high osmotic pressure and a paste part.

CONSTITUTION: The objective sheet comprising plural sheets of a semipermeable membrane part (made of a flexible material such as polyvinyl alcohol for food) 4-1 and 4-2 passing through only water and a fishiness component from a food a food part (made of an edible saccharide such as thick malt syrup) 6 having high osmotic pressure to absorb water from the food by osmotic pressure laid between the semipermeable membrane parts 4-1 and 4-2, a paste part (made of food additive paste such as sea tangle composition, etc.) 8 to retain absorbed water and optionally an alcohol.