A crustacean-derived protein, as measured by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, displays a non-reduced band of a molecular weight of about 200,000, displays reduced-form bands at about 86,000 and 90,000 molecular weights, and has N-terminal amino acids as indicated by SEQ ID No. 1 or SEQ ID No. 2. This protein is contained in large amounts in the crustacean shells that are largely discarded except for use for meal, chitin, and chitosan raw material. Thus large volume preparation, as well as inexpensive production, is possible. Moreover, application by addition to foods is easy since this is a food-derived protein. Since the protein of the present invention has ice nucleation activity and recrystallization inhibition activity for ice crystals, wide use is possible with the object of quality maintenance and the like of frozen food and the like.